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1- If a manifold pressure gauge consistently registers atmospheric pressure, the cause is probably: A) ice in induction system. B) too high float level. C) fuel of too low volatility. D) leak in pressure gauge line . 2- A manifold pressure gauge of a piston engine measures: A)fuel pressure leaving the carburetor. B)vacuum in the carburetor. C)absolute pressure in intake system near the inlet valve. D)absolute air pressure entering the carburetor. 3- An aneroid capsule:

1)measures differential pressure. 2)measures absolute pressure . 3)is used for low pressure measurement . 4)is used for very high pressure measurement . The combination regrouping all the correct statements is:

A) 1,3 B) 2,3 C) 2,4 D) 1,4 4- On A/C with a fuel pressure gauge, where is the pressure normally measured? (Aircraft with fuel injection) A)Tank outlet. B) Selector valve outlet. C)At the injection nozzles. D)Inlet of the fuel injection metering unit.. Metal capsules (or diaphragms) are normally used as sensors or measuring oil and fuel pressures. These are connected by an electrical transmission system to the indicators. In some modern aeroplanes the piezo electric type of sensor is the favored option. Fuel pressure is typically measured at the outlet of the high pressure fuel pump = in case of piston engines at the inlet to the carburetor or the fuel injection metering unit, in case of turbine engines at the inlet of the fuel control(metering) unit. 5- Absolute pressure is: A)The difference between two pressures. B)The amount the pressure has been raised with reference to an initial level. C)Measured from zero pressure(vacuum). D)Pressure in A confined area. Absolute pressure is pressure above absolute zero, that is the difference between the pressure being measured and the pressure in a complete vacuum.

6- The temperature measured by the CHT (Cylinder Head Temperature) prone is the: A)temperature of the exhaust gases.

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B)average temperature within the whole set of cylinders. C)temperature within the hottest cylinder ,depending on its position in the engine block. D)temperature of the carburetor to be monitored when the outside air temperature is between -5 C and 10 C.

The thermal efficiency of a piston engine is on the average around only 30%. It means that out of the entire thermal energy released during the combustion of the fuel/air charge only 30% is used as mechanical work for driving the piston during the power stroke. Heat energy leaves the combustion chamber during the exhaust stroke through the exhaust manifold, but a major part is dissipated into the cylinder heads as heat. The temperature of the cylinder heads can be often monitored by the pi/at using the Cylinder Head Temperature (CHT) gauge. It typically uses the principle of a thermocouple attached to the cylinder => the thermocouple produces voltage proportional to the temperature and it is then indicated in the cockpit as temperature. Some relatively simple aircraft may have only 1 CHT sensor installed in the engine - in this case it will be attached to the hottest cylinder - typically this will be one of the cylinders in the rear part of the engine, away from the ram-air intake (= receives the lowest portion of the cooling ram-air flow). On aircraft where the CHT sensor is attached to every cylinder the gauge will indicate temperatures for each of these cylinders. The readouts will never be averaged among two or more cylinders. The gauge might be a digital indicator showing the temperatures of all cylinders or it can be a simple analog gauge with a switch button to select the specific cylinder the pilot wishes to monitor

7- To permit turbine exit temperatures to be measured, gas turbines are equipped with thermometers which work on the following principle:

A) bi-metallic strip. B) thermocouple. C)liquid expansion. D) gas pressure.

8- The yellow sector of the temperature gauge corresponds to:

A) a frequent operating range. B) a normal operating range. C) an exceptional operating range. D) a forbidden operating range.

Some aircraft types include temperature indications with coloured segments. The colours are similar to the function of a traffic light (green, yellow and red). • BLACK or GREEN = Normal operating range • WHITE = Special conditions operating range • AMBER or YELLOW = Abnormal and Caution, Exceptional operating range

RED = Out of Limits or Danger range

9- A pitot tube covered by ice which blocks the ram air inlet will affect the following instrument(s):

A) altimeter only. B) airspeed indicator only. C) vertical speed indicator only. D) airspeed indicator, altimeter and vertical speed indicator.

(Refer to figure 022-E51) Various sections of the pitot-static system can become blocked. The blockage can occur as a result of dirt or insect ingestion, or as a result of water ingestion that subsequently freezes in the pitot-static

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system and forms an ice block. There was even a case of a large transport aircraft accident which resulted from the static ports being covered by a piece of tape (to protect them during aeroplane wash-ing) - the maintenance staff and the pilots failed to nice the tapes has been forgotten in place and took off - crashing after a brief flight as a result of erroneous instrument indications. Blocked pitot tube A blocked pitot tube is a pitot-static problem that will only affect airspeed indicators. Pitot tube senses a total pressure. A blocked pitot tube will cause the airspeed indicator to incorrectly display an increase in airspeed when the aircraft climbs, even though indicated airspeed is constant. This is caused by the total pressure in the pitot system remaining constant (held constant by the blockage at a value at which the blockage occurred) and at the same time the atmospheric pressure (static pressure) decreasing due to the aircraft climbing ==> tl1is will produce a greater difference between the total and static pressures, which will be indicated by the airspeed indicator as an increased speed. In reverse, the airspeed indicator will show a decrease in airspeed when the aircraft descends. So, in essence the instrument will begin to function in a similar way to an altimeter. The pitot tube is susceptible to becoming clogged by ice, water, insects or some other obstruction. For this reason, aviation regulatory agencies such as the EASA or FAA recommend that the pitot tube be checked for obstructions prior to any flight. To prevent icing, many pitot tubes are equipped with a heating element. A heated pitot tube is required in all aircraft certificated for instrument flight. Blocked static port A blocked static port is a more serious situation because it affects all pitot-static instruments. One of the most common causes of a blocked static port is airframe icing. A blocked static port will cause the altimeter to freeze at a constant value - at the altitude at which the static port became blocked. The vertical speed indicator will gradually return to zero and become frozen at zero - it will not change at all, even if vertical airspeed increases or decreases. The airspeed indicator will reverse the error that occurs with a blocked pitot tube and cause the airspeed be read less than it actually is as the aircraft climbs. When the aircraft is descending, the airspeed will be over-reported. So, in essence the airspeed indicator acts in the reverse of an 'altimeter. In most aircraft with unpressurized cabins ,an alternative static source is available and can be toggled from

within the cockpit of the airplane. Partial blockage of static port

If the static reference system is severely restricted, but not entirely blocked, as the airplane descends, the static reference pressure at the instruments begins to lag behind the actual outside air pressure. While descending, the altimeter may indicate that the airplane is higher than actual because the obstruction slows the airflow from the static port to the altimeter. The vertical speed indicator confirms the altimeter's information regarding rate of change, because the reference pressure is not changing at the same rate as the outside air pressure. The airspeed indicator, unable to tell whether it is experiencing more airspeed pitot pressure or less static reference pressure, indicates a higher airspeed than actual. To the pilot, the instruments indicate that the airplane is too high, too fast, and descending at a rate much less than desired.

10- If an aircraft is equipped with one altimeter which is compensated for position error and another altimeter which is not, and all other factors being equal:

A) there will be no difference between them if air the data computer is functioning normally. B) at high speed, the non compensated altimeter will indicate a higher altitude. C) at high speed the non compensated altimeter will indicate a lower altitude. D) ATC will get an erroneous altitude report SSR.

11- The pressure measured at the forward facing orifice of a pitot tube is the:

A) static pressure. B) total pressure. C) total pressure plus static pressure. D)dynamic pressure.

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(Refer to figure 022-E51) The pitot tube measures the total pressure (PT).The static vent measures the static pressure (Ps).There are also pitot tubes that measure the PT at the forward facing orifice and the Ps at the side orifices - in this setup we refer to them as the "pressure heads", but they were replaced with a simple pitot tubes that measure only PT. The reason being a large position error on the static ports created by the turbulence around the pitot tube itself. Therefore, the static vents have been relocated to their most frequent location - side of a fuselage. Ps is the ambient air pressure - the pressure that acts on all parts of the aircraft when stationary on the ground.

Dynamic pressure (also called the ram air pressure) - PD - is the extra pressure exerted on the frontal parts of the aircraft when it object moves through the air (it is actually the resistance of the air to that movement). Thus, PD increases with increased speed of the aircraft and with increased density of the air (PD ==1/2 pv2). The frontal parts of the aircraft (leading edges, nose, etc.) are therefore exposed to both the static pressure (Ps) and the dynamic pressure (PD).By adding these two values we get the Total pressure (PT) =PS+PD . The front part of the pitot tube (the forward facing orifice) is therefore sensing Total pressure. The combined use of the pitot tube (PT) and the static vent (Ps) provides speed information - the dynamic pressure (PD = PT – PS==> the ASI (Air Speed Indicator) and the Machmeter utilise both the static vent and the pitot tube.

12- In a non-pressurized aircraft, if one or several static pressure ports are damaged, there is an ultimate emergency means for restoring a practically correct static pressure intake:

A)calculating the ambient static pressure, allowing for the altitude and QNH and adjusting the instruments.

B) descending as much as possible in order to fly at a pressure as close to 1.013,25 hPa as possible.

C) slightly opening a window to restore the ambient pressure in the cabin. D) breaking the rate-of-climb indicator glass window.

Many aircraft certified for flight in IMC (instrument meteorological conditions) are equipped with an alternate static port. If for some reason the primary static port becomes blocked (for example by ice) the pilot can switch to the alternate static source. If the alternate static source is not available (not installed) or in case it is also blocked for any reason, then the best way how to solve the situation if in an unpressurized aircraft is to break the glass of the vertical speed indicator (VSI). In this way the cabin pressure will replace the static pressure source for an emergency operation. In a non-pressurized aircraft, the outside static pressure is approximately equal to the cabin static pressure. We say almost, because the cabin pressure is very slightly less than the outside pressure (very simply said due to the speed of the aircraft and subsequent "suction" of cabin air out around the windows, doors, which are not air tight, etc.).

13- A dynamic pressure measurement circuit is constituted of the following pressure probes:

A) total pressure and static pressure. B) static pressure only. C) total pressure only. D)total pressure and standard pressure.

14- An aircraft is equipped with one altimeter that is compensated for position error and another one altimeter that is not. Assuming all other factors are equal, during a straight symmetrical flight:

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A) the greater the speed, the greater the error between the two altimeters. B) the greater the speed, the lower the error between the two altimeters. C) the lower the speed, the greater the error between the

two altimeters. • D)the error between the two altimeters does not depend' on the speed.

15- Given: P T = total pressure PS = static pressure PD = dynamic pressure

A) PD=PT+PS S) PT=PD+PS C) Ps = PT + PD D) PD = PT /Ps

16- Given: P T = total pressure P s = static pressure Pso = static pressure at sea level Dynamic pressure is:

A) (P T _P S) /P s B) PT_PSQ C) (PT_PSO)/Pso D)PT_PS

17-If the pitot tube ices up during a flight, the affected equipment(s) is (are):

1)the altimeter 2)the variometer 3)the airspeed indicator The combination regrouping all the correct statements is:

A)1,2 B) 1,2,3 C)1,3 D)3

18- If during a descent: -the pneumatic altimeter reading is constant - the VSI shows zero -the IAS is increasing the most likely explanation is that:

A) the static intakes are completely clogged up by ice. B) the total pressure intake is completely clogged up by ice. C) there is a leakage in the static pressure line. D) the antenna of the radio altimeter is completely clogged up by ice.

19- The position error of the static vent on which the altimeter is connected varies

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substantially with the: A) flight time at high altitude. B) speed of the aircraft. C) altitude of the aircraft. D)outside air temperature.

20-The total pressure probe (pitot tube) comprises a mast which moves its port to a distance from the aircraft skin in order:

A) to locate it outside the boundary layer. B) not to disturb the aerodynamic flow around the aircraft. C) it is protected from icing. D)it is easily accessible during maintenance checks. The pitot tube comprises a mast which moves its port to a certain distance from the aircraft skin in order to sense the true total pressure (PT), without any inaccuracies that may appear from the boundary layer.

21- Which of the following instruments are connected to the pitot-static system? 1)altimeter 2) air-operated directional gyro 3)vertical speed indicator 4)airspeed indicator

The combination regrouping all the correct statements is: A)1,3 B) 1,3,4 C) 1,2,3,4 D)1,2,4

(Refer to figure 022-E51) There are three instruments connected to the pitot-static system: •Airspeed indicator (ASI) • Vertical speed indicator (VSI) - sometimes called the variometer • Altimeter.

All of these instruments are supplied with static pressure information - the source of the static pressure being the static pressure port. In addition, the airspeed indicator is also supplied with the total pressure (ram pressure) information - source of the total pressure being the pitot tube. Airspeed is then derived as Dynamic pressure = Total pressure - .Static pressure.

Note 1: when we talk about the pitot-static system, we do not mean only the pitot tube. Pitot static system comprises both the pitot tube and the static port. Note 2: do not confuse the pitot-static system with the vacuum system for the air-driven gyroscope operation. Vacuum gauge is not part of a pitot-static system.

22- If the static vent becomes blocked due to ice on an unpressurized aircraft, what can you do?

A) Select standby pitot source. B) Break the VSl glass.

C)The altimeter will function as airspeed indicator - an increase in airspeed will be indicated as a climb; decrease in airspeed as descent.

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D)The altimeter will function as airspeed indicator - an increase in airspeed will be indicated as a descent; decrease in airspeed as climb.

23-Which Instrument does not connect to the static system? A) Altimeter. B) Vacuum gauge. C) Airspeed indicator. D)Vertical speed indicator.

24- The standard temperature for all our aerodynamic computations is:

A) O°C or 32°F. B) 15°C or 59 °F. C)273 K or 492°R. D)0°F or 460 °R.

A straightforward question! The standard MSL temperature for aerodynamic computations is 15"C or 59°F (for our friends on th6 other side of the Atlantic)

25-The QNH is by definition the value of the: A) altimeter setting so that the needles of the altimeter indicate the altitude of the location for

which it is given. B) atmospheric pressure at the sea level of the location for which it is given. C) altimeter setting so that the needles indicate zero when the aircraft is on ground at the

location for which it is provided. D) atmospheric pressure at the level of the ground overflown by the aircraft .

The setting to altimeters to datum barometric pressures is part of flight operating procedures and is essential for maintaining adequate separation between aircraft and terrain clearance during take-off and landing. Titles for the settings have been adopted universally and form part of the ICAO "Q" code of communication, The code consists of three-letter groups, each having "Q" as the first letter. Those normally used in relation to altimeter settings are: • QFE Setting - the pressure prevailing at an airfield, the setting of which on the altimeter subscale will cause the

altimeter to read zero on landing and toke-off: • QNE Setting - the standard pressure setting of 1013.25 hPa causes the altimeter to indicate the pressure altitude

in the standard atmosphere. • QNH Setting - the pressure scale to make the altimeter read airfield elevation on landing and take-off. QNH is the most frequently used altimeter setting Q-code and stands for "Quasi-Nan-Hydrostatic". It is a pressure setting used by pilots and air traffic control (ATC) to refer to the barometric altimeter setting which will cause the altimeter to read true altitude above mean sea level (MSL) within a certain defined region. This region may be fairly widespread, or apply only to the airfield for which the QNH was given. An airfield ONH will cause the altimeter to read field elevation on landing irrespective of the temperature. When altimeter indication is based on a QNH setting, the readout is referred to as “altitude” (=height above mean sea level).QNH differs from QFE.QFE refer to the altimeter setting that will cause the altimeter to read the height above a specific aerodrome ,and therefore zero on landing.

26- If the static source of an altimeter becomes blocked during a descent the instrument will:

A) continue to display the reading at which the blockage occurred.

B) gradually indicate zero.

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C) under-read. D)indicate a height equivalent to the setting on the millibar subscale.

27-The density altitude is:

A)the pressure altitude corrected for the density of air at this point.

B)the temperature altitude corrected for the difference between the real temperature and the standard temperature. C)the pressure altitude corrected for the relative density prevailing at this point.

D)the altitude of the standard atmosphere on which the density is equal to the actual

density of the atmosphere. Altitude is vertical distance above some point or level used as a reference. There are as many kinds of altitude as there are reference levels from which altitude is measured, and each may be used for specific reasons. Pilots are mainly concerned with five types of altitudes:

• Indicated altitude - the altitude read directly from the altimeter (uncorrected) when it is set to the current

altimeter setting (QNH).

• True altitude - the vertical distance of the airplane above sea level ~ the actual altitude. It is often expressed as feet above mean sea level (MSL). Airport, terrain, and obstacle elevations on aeronautical charts are true altitudes. True altitude will be equal to indicated altitude only in standard ISA conditions. • Absolute altitude (or height) - the vertical distance of an airplane above the terrain, or above ground level

(AGL).

• Pressure altitude - the altitude indicated when the altimeter setting window (barometric scale) is adjusted to 1013 mb. This is the altitude above the standard datum plane, which is a theoretical plane where air pressure (corrected to 15DC) equals 1013 mb (29,92 in.Hg): Pressure altitude is used to compute density altitude, true altitude, true airspeed, and other performance data. In other words, the pressure altitude = altitude in the standard atmosphere at which the prevailing pressure is equal to the pressure in the standard atmosphere.

• Density altitude - this altitude is pressure altitude corrected for variations from standard temperature.

When conditions are standard, pressure altitude and density altitude are the same. If the temperature Is above standard, the density altitude is higher than pressure altitude. If the temperature is below standard, the density altitude is lower than pressure altitude. This is an important altitude because it is directly related to the airplane's performance. In other words, the density altitude = altitude in the standard atmosphere at which the prevailing density is equal to the density In the standard atmosphere.

As an example, consider an airport with a field elevation of 5.000 ft MSL where the standard temperature is 5 DC. Under these conditions, pressure altitude and density altitude are the same (5.000 ft). If the temperature changes to 30 °C, the density altitude increases to 7.800 ft. This means an airplane would perform; on takeoff as though the field elevation were 7.800 ft at standard temperature. Conversely, a temperature of -25° C would result in a density altitude of 1.200 ft. An airplane would have much better performance under these conditions. Standard atmosphere (ISA) conditions are:

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• Pressure at MSL = 1013,25 mb • Density = 1225 g/m3 • Temperature 15° C at MSL and decreasing at 1,98 °C per 1000 ft up to 36.090 ft • Constant temperature of 56.5 °C from 36.090 ft to 65.617 ft • Temperature increasing with 0,3° C per 1000 ft from 65.617 ft to 104.987 ft 28-The pressure altitude is the altitude corresponding:

A) in ambient atmosphere, to the pressure Ps prevailing at this point. B)in ambient atmosphere, to the reference pressure PS C) in standard atmosphere, to the reference pressure PS. D) in standard atmosphere, to the pressure PS prevailing at this point.

29- If the static source to an altimeter becomes blocked during a climb, the instrument will:

A) under-read by an amount equivalent to the reading at the time that the instrument became blocked. B) continue to indicate the reading at which the blockage occurred.

C) over-read. D) gradually return to zero.

30- On board an aircraft the altitude is measured from the: A) density altitude. B) pressure altitude. C) temperature altitude. D) standard altitude.

31- When flying from a sector of warm air into one of colder air. the altimeter will:

A) be just as correct as before. B) under-read. C) over-read. D) show the actual height above ground.

(Refer to figures 022-E47 and 022-E48)

Temperature error arises whenever mean atmospheric conditions below the aeroplane differ from the standard atmosphere. The operating principle of the altimeter is based on the measurement of the static pressure. The pressure decreases when altitude increases. Temperature and pressure are indirectly proportional - if the temperature increases, air expands and its pressure decreases (implies higher altitude). If the temperature decreases, pressure increases (implies lower altitude). Basically, if the actual temperature lapse rate differs from the assumed one, then indicated height will be incorrect. In general, if the air below the aeroplane is warmer than standard, the air will be less dense end- the aircraft will be higher than indicated (altimeter under-reads). If colder than standard, the air will be more dense and the aeroplane will be lower than standard '(altimeter over-reads). Correct height may be obtained from that in-dicated by use of the navigation computer. For "rule of thumb" work, a temperature difference of 10°C from standard, will cause an error of approximately 4% of indicated height. Some teachers use the saying, "high to low =:> look out below" to aid in memorization of this principle. We should "look out below" because the actual altitude of the aircraft will be lower than the indicated one on the altimeter (altimeter over-reads)

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32-(Refer to figure 022-22) The atmospheric pressure at FL70 in a STANDARD +10 atmosphere is:

A) 942,85 hPa B) 781,85 hPa C) 1013,25 hPa D) 644,41 hPa

'There is no need for complicated calculation on this questions. Question states “flight level” = pressure level (pressure altitude). If this pressure level rises or falls due to temperature changes, we will follow it with our aircraft and the pressure remains the same. In other word, for the altimeter to indicate FL70 it must sense static pressure equivalent to 7.000 ft in standard conditions. Therefore, simply locate a value of 7. 000 ft in the first column of the table - then proceed to the right and read the equivalent pressure at 7.000 ft =:> 782 mb (=: 782 hPa).

33-The altitude indicated on board an aircraft flying in an atmosphere where all the atmosphere layers below the aircraft are cold is:

A) equal to the standard altitude. B) the same as the real altitude. C) lower than the real altitude. D) higher than the real altitude.

34- The altitude indicated on board an aircraft flying in an atmosphere where a/l atmosphere layers below the aircraft are warm is:

A) higher than the real altitude. B) lower than the real altitude. C) equal to the standard altitude. D) the same .as the real altitude.

35- The altimeter consists of one or several aneroid capsules located in a sealed casing. The pressures in the aneroid capsule (i) and casing (ii) are respectively:

A) (i) static pressure; (ii) total pressure. B) (i) static pressure at time t; (ii) static pressure at time t -t.

C) (i) total pressure; (ii) static pressure. D)(i) vacuum (or a very low pressure); (ii) static pressure.

(Refer to figures 022-E47 and 022-E48)

The altimeter is an instrument that is designed to measure static pressure (just like an aneroid barometer) and, using the conditions of the standard atmosphere, convert that pressure into a value of altitude. The sensitive altimeter has a minimum of two aneroid capsules containing either vacuum Dr very low pressure. This provides for a more accurate measurement of pressure and also provides more power to drive the mechanical linkage. The capsules are stacked together with one face fastened down, permitting movement due to pressure changes at the other end. The movement of the capsules in response to change in height (static pressure) is transmitted via a suitable mechanical linkage to three pointers that display (against a graduated instrument scale) the aircraft height in tens, hundreds and thousands of feet. The whole assembly is encased in a container, which is fed with static pressure, but is otherwise completely airtight. Within the mechanical linkage a bi-metallic insert is fitted to compensate for temperature changes that

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could affect the movement. As the aircraft climbs and air pressure falls, the capsules expand; similarly, as the aircraft descends, static pressure increases and the capsules contract. Since it is necessary to allow for different values of mean sea level pressure and to allow the altimeter to be used for indicating height above the aerodrome, the pilot must be provided with a means of adjusting the level at which the altimeter indicates zero feet. Fitting a barometric subscale mechanism does this. This adjusts the mechanical linkage and operates a set of digital counters, or calibrated dial. This displays in a window in the face of the altimeter the datum pressure setting above which the instrument is now displaying altitude. The desired setting is made using the knurled knob at the bottom of the instrument.

36- The altimeter is supplied with: A) differential pressure. B) static pressure. C) dynamic pressure. D) total pressure.

37- An aircraft is flying at an indicated altitude of 16.000 ft. The outside air temperature is ~30 DC. What is the true altitude of the aircraft?

A) 16.200 ft B) 15.200 ft C) 18.600 ft D) 13.500 ft

First we need to find the ISA at 16.000 ft => -17 ·C (15 - (16 x 2). The actual temperature is -30 ·C, therefore the conditions are ISA13". To obtain the true altitude, we need to decrease the indicated altitude by 4% for every 10· below standard temperature - in this case our temp is 13· colder than standard »> that means instead of 4% we have to decrease it by 5,2% (4 x 1,3). The altitude reduction due to temperature is 832 ft (16.000 x 0,052) => therefore the true altitude Is 15.168 ft (16.000 - 832).

38- An aircraft is flying straight and level, over a warm air mass. The altimeter reading will be: A) correct. B) greater than the real height. C) less than the real height. D) oscillating around the correct height.

39-An altimeter contains one or more aneroid capsules. Inside these capsules is:

A) dynamic pressure and outside is static pressure. B) static pressure and outside is dynamic pressure. C) a very low residual pressure and outside is static pressure.

D)static pressure and outside a very low residual pressure.

40- Due to its conception, the altimeter measures a: A) temperature altitude. B) density altitude. C) pressure altitude. D) true altitude.

41- The altimeter indicates true altitude:

A) when the temperature on the ground is +15°C with a lapse rate of 2°C per 1.000 feet, and correct QNH is set.

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B) in ISA conditions only. C)when the temperature on the ground is +15°C with a lapse rate of 2°C per 1.000 feet, and correct QFE is set. D)when pressure at mean sea level is 1013,25 hPa, with a ground temperature of +15°C and a density equal to 1,225 kg/m3.

42- The altimeter is supplied with:

,A) static pressure. B) dynamic pressure. C) total pressure. D) differential pressure.

43- The altimeter of your aircraft indicates 10.000 ft with a subscale-setting of 1013,25 mb. OAT is +5° C. The pressure altitude of the aircraft is:

A) 697 hPa B) 10.400 ft C) 9.600 ft D) D)10.000 ft

With the value of 1013,25 mb set In the altimeter subscale window the altimeter directly Indicates a pressure altitude. In this case your indicated altitude = pressure altitude. There is no need for any calculations 44- The altimeter of your aircraft indicates 11.000 ft with a subsea/e-setting of 1013,25 mb. The QNH is 1023 hPa. OAT is +3 CC. The pressure altitude of the aircraft is:

A) 10.260 ft B) 11.740 ft C)11.000 ft D) 670 hPa

45- The altimeter of your aircraft indicates 12.000 ft with a subscale-setting of 1013,25 mb. QNH is 999 hPa. The pressure altitude of the aircraft is:

A) 644 hPa B) 11.580it C) 12.420ft D) 12.00'0 ft

46-The altimeter of your aircraft indicates 15.000 ft with a subscale setting of 1013,25 mb. OAT is -21 °C. The pres- sure altitude of the aircraft is:

A) 15.000 ft B) 14.640 ft C)15.360 ft

47- The altimeter of your aircraft indicates 16.000 ft with a subscale setting of 1013,25 mb. QNH is 993 hPa. OAT is _3°C. The pressure altitude of the aircraft is:

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A) 16.000 ft B) 14.200 ft C)17.700 ft D) 548 hPa

48- The altimeter of your aircraft indicates 17.000 ft with a subscale setting of 1013,25 mb. QNH is 1.031 hPa. The pressure altitude of the aircraft is:

A) 17.540 ft B) 17.000 ft C)16.460 ft D)527 hPa

49- The QNH is by definition the value of the: A) atmospheric pressure at the location for which it is given, corrected for non-standard

temperature. B) altimeter setting so that the altimeter, on the apron of the aerodrome for which it is given,

reads the elevation. C) altimeter setting so that the altimeter, on the. apron of the aerodrome for which it is given,

reads zero. D) atmospheric pressure at the level of the ground over-flown by the aircraft.

50- When flying in cold air (colder than standard atmosphere), indicated altitude is:

A) lower than the true altitude. B) the same as the true altitude. C) higher than the true altitude. D) equal to the standard altitude.

51- When flying in cold air (colder than standard atmosphere), the altimeter wi11: A) show the actual height above the sea level. B) underestimate. C) overestimate. D) show the actual height above ground.

52- When flying in warm air (warmer than standard atmosphere), indicated altitude is:

A) higher than the true altitude. B) the same as the true altitude. C) lower than the true altitude. D) equal to the standard altitude.

53- QNH is:

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.A) the airfield barometric pressure. B) the setting that will give zero indication on the airfield. C) the equivalent sea level pressure at the airfield. D)the standard pressure setting of 1013 hPa.

54- What is density altitude?

A) Altitude in the standard atmosphere at which the prevailing density is equal to the density in the standard atmosphere.

B) Indicated altitude corrected for non-standard temperature. C) Temperature altitude.

D)Pressure corrected.

55- What will the altimeter read if the layers beneath the aircraft are all colder than standard? A) Read lower than the real altitude. B) Read higher than the real altitude. C) Read the correct altitude. D) Readings will fluctuate.

56- Pressure altitude may be defined as; A) the lowest forecast regional pressure. B) pressure measured in the standard atmosphere. C) altitude indicated with QFE set on the altimeter. D) altitude indicated with QNH set on the altimeter.

57- What is the effect on an altimeter reading if variations in

static pressure occur near to the pressure source? A) A change in hysterysis error. B) A change in the instrument error. C) A change in the position error. D) A change in the compressibility error.

(Refer to figures 022-E47 and 022-£48)

Pressure (position) error refers to the small inaccuracy in sensing the actual static pressure. It is caused by the fact that the air around the static ports is slightly turbulent. The airflow being turbulent, the sensed static pressure will be lower than the true static pressure and a lower pressure corresponds to a higher altitude. Position error increases as the aircraft speed increases (high Mach numbers = bigger position error). If the altimeter is not compensated for position error, it will indicate higher than the actual altitude at higher aircraft speeds. The position error is tabulated in the aircraft flight manual. Position error can also be influenced by configuration changes (flaps/gear) - in a way that extension of flaps and/or gear may affect airflow around the static ports.

58- In an a1timeter, what pressure is fed to the capsule and the case? A) Static/dynamic. B) Static/static. C) Static/vacuum.

D)Vacuum/static.

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59- When flying in cold air (colder than standard atmosphere), the altimeter will: A) show the actual height above ground. B) be just as correct as before. C) over-read. D) under-read.

60- The altitude given by an altimeter is: A) a pressure altitude. B) a density altitude. C) a temperature altitude. D) a true altitude.

61- If the alternate static source is used, the resulting reading will be:

A) too low reading of altitude. B) too high reading of altitude. C)too low reading of airspeed. D)no reading of airspeed.

Some aircraft are equipped with an alternate source of static pressure for the pitot-static instruments in case the main source of static pressure becomes blocked - for example by ice. On unpressurized aircraft this alternate static source typically takes the static pressure from the cabin of the aircraft. Because there is no 100% sealing around cabin doors, windows and other openings, some air is sucked out of the cabin by the Venturi effect. Therefore, the static pressure inside the cabin becomes slightly lower than the outside static pressure. The altimeter will interpret lower static pressure as higher altitude, therefore the altitude indication will increase, but the true altitude in reality is maintained constant. The altimeter will therefore over-read slightly

62- When flying" with an indicated altitude of 3.000 ft into a low pressure area, the actual altitude:

A) will decrease. B) will increase. C) will be the same as indicated altitude. D) will be as before entering a low-pressure area.

(Refer to figures 022-E47 and 022-E48) Barometric error occurs when the "actual datum level pressure differs from that to which the subscale has been set. A subscale error of 1 hPa is equivalent to an indicated altitude error of 28 to 30 feet. For example - the aircraft is flying with a QNH of 1013 set in the altimeter subscale (= standard atmospheric conditions). However, if the pressure changes to a lower value - for example to 995 mb, this represents an altitude change of540 ft (30 ft x (1013 mb- 995 mb)). The subscale datum must now be at a point that is effectively 540 ft below sea level and this is the level from which the altimeter is measuring. If the pilot does not reset the altimeter to this new QNH the altimeter will over-read. Remember, that if QNH decreases and you did not reset the altimeter, it will indicate a higher altitude than the actual altitude (over-read). If the QNH increases and you did not reset the altimeter setting, it will indicate a lower altitude than the actual one (under-read). Again the saying "high to low => look out below" is applicable here and helps in memorization of this principle. We should "look out below" because the actual altitude of the aircraft will be lower than the indicated one on the altimeter (altimeter over-reads). 63- The altimeter is based upon the same principle as:

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A) the aneroid barometer. B) the hygrometer. C) the mercury barometer. D)the Bourdon tube manometer.

64- When the barometric subscale of the altimeter is adjusted to 1013,2 hPa, what type of altitude is being measured?

A) Relative height. B) Pressure altitude. C) Indicated altitude. D)True altitude.

65-When the sea level OAT is +25 °C, the deviation from standard temperature for aerodynamic computations is:

A) 008 B) +15 °C C) -15°C D) +10 °C

Standard temperature at sea level is 15cC, with a lapse rate of2' per 1.000 of altitude (for every 1.000 ft altitude increase the temperature drops by 2·C). Therefore, if we have a temperature of +25'C at sea level, the conditions are 10· warmer than standard (we say ISA+10). 66- Without re-adjusting the barometric setting of the altimeter, it will under-read when:

A) flying from a low pressure area into a high pressure] area. B) flying from a high pressure area into a low pressure area. C) flying in headwind with constant barometric pressure. D)Flying in tailwind with constant barometric pressure

67- We are maintaining a constant flight level. That means:

A) the altitude above sea level is constant. B) the outside air pressure is constant. C) the altitude is constant when the sea level pressure is constant. D)the outside air pressure is constant if the temperature remains constant.

Maintaining a constant flight level means that you are flying along' the same isobaric surface, i.e. the pressure outside the aircraft is! constant (you are following a constant pressure level difference to a! pressure datum of 1013 mb). Note that it doesn't mean that the true altitude is constant.

68- If the altimeter indicated 0 ft when the aircraft was parked for the night, and 1.000 ft the following morning" this shows that:

A) the barometric pressure has increased by approx. 33 hPa. B) the barometric pressure has decreased by approx. 33 hPa. C) the barometric pressure is constant, but the tempera .. ture has fallen during the night.

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D)a formation of fog has most probably taken place. If the altimeter "thinks" it has climbed, it means that the pressure has decreased. At sea level, the pressure gradient is approximate/]1 30 ft per hPa-(some books say 28 ft per hPa), which has been rounded to 30 ft in this question. That means for an indicated altitude - change of 1.000 ft to occur, the pressure must have decreased by 33 hPa (1.000 ft + 30 ft = 33 hPa).

69- An aircraft is maintaining a level flight at FL 100 over a mountain range, which extends up to 2.400 metres AMSL. If the regional QNH is 998 hPa (use 30 ft/hPa), what is the approximate terrain clearance?

A) 2.581 feet B) 1.680 feet C) 7.869 feet D)450 feet

. First we need to convert the elevation of the mountain into feet using a formula that states 1 meter = 3,28 ft. The mountain range extends to 2400 meters x 3,28 ft = 7.872 ft. Since we are maintaining a Flight Level that means our altimeter subscale is set to a value of 1013 mb. Compare this setting (1013) to the local QNH of 998 mb. The difference is 15 mb. At 30 ft per 1 mb that would represent a height of 450 ft. Since we are flying on altimeter setting of 1013 mb while the actual QNH is lower (998 mb) it means that our altimeter is indicating a pressure altitude that is higher than the true altitude. This could be evidenced by simply changing the altimeter setting to the correct local QNH value of 998 mb and we would see the altimeter pointers wind down to indicate an altitude 450 ft lower. That means our true altitude is 9.550 ft. If the mountains below us are 7.872 ft high, we are 1.678 ft above them (9.550 - 7_872).

70- You are departing an aerodrome (600 ft AMSL, QNH 1012 hPa) and proceed to another airfield (150 ft A MSL) with the same QNH. After landing, which barometric setting on the altimeter makes it again indicate 600 ft?

A) 1027 B) 997 C) 1032 D) 992

You are flying from an airport at 600 ft above sea level to another airport at 150 ft above sea level. The elevation difference is 450 ft. The question states that we have the same altimeter setting at both airports (1012 hPa). So, if we wish to increase the reading back up to 600 ft, we will need to roll the altimeter knob clockwise (= to a higher altimeter setting value) in order to increase the reading. Going with the generally accepted assumption that at low altitudes 1 mb = 30 ft, we can do a simple calculation: 450/ 30 = 15 mb. Adding 15 mb to 1012 gives us 1027 mb

71- The operating principle of the vertical speed indicator (VSI) is based on the measurement of the rate of change of:

A) kinetic pressure. B) dynamic pressure. C) total pressure. D) static pressure.

(Refer to figure 022-E03)

Although the vertical speed indicator (VSI) operates solely from static pressure, it is a differential pressure instrument. It contains a capsule with connecting linkage and gearing to the indicator pointer inside an airtight

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case. The inside of the capsule is connected directly to the static line of the pitot-static system. The area outside the capsule, which is inside the instrument case, is also connected to the static line, but through a restricted opening (calibrated leak). Both the capsule and the case receive air from the static line at existing atmospheric pressure. When the airplane is on the ground or in level flight, the pressures inside the capsule and the instrument case remain the same and the pointer is at the zero indication. When the airplane climbs or descends, the pressure inside the capsule changes immediately, but due to the metering action of the restricted passage, the case pressure remains higher or lower for a short time, causing the capsule to contract or expand. This causes a pressure differential that is indicated on the instrument needle as a climb or descent. When the pressure differential stabilizes at a definite ratio, the needle indicates the rate of altitude change. In other words, the VSI measures the difference between the instantaneous (current) static pressure and the static pressure at a previous moment

72- The response time of a vertical speed detector may be improved by adding a: A) return spring. B) bimetallic strip.

C) correction based on an accelerometer sensor. D) second calibrated port.

(Refer to figure 022-E04) One of the errors that the VSI units experience is the time lag. Since the VSI measures a differential pressure (between the actual static pressure and a previous static pressure), it requires several seconds of "adjusting" to be indicating accurately, and the indicated vertical speed is reliable only when the flight is stable, unaccelerated. When an aircraft suddenly starts to climb or descend, a delay of a few seconds occurs before the pointer settles at the appropriate rate of climb or descent, due to time required for the pressure difference inside the instrument to develop. Therefore we can say that the VSI indicates a trend in change of vertical speed almost instantaneously, but an accurate rate of climb/descent is indicated only after a few seconds of steady climb or descent. The lag error can be solved by using "Instantaneous VSI units" (referred to as the "IVS”): The IVSI consists of the same basic elements as conventional VSI, but in addition employs an accelerometer unit which is designed to create a more rapid differential pressure effect; specifically, at the initiation of climb or descent. The accelerometer comprises two small cylinders or dashshpots containing pistons (we can also refer to them as "accelerator pumps") held in balance by springs and their own mass. The cylinders are connected in the capillary tube system leading to the capsule and are thus open to the static pressure source. When a change in vertical motion is initiated, the force that results from the vertical acceleration displaces the pistons. This creates an immediate pressure change inside the capsule and an instantaneous movement of the indicator pointer. The accelerometer output decays after a few seconds, but by this time the change in actual static pressure is effective. Errors are generally the same as those affecting the conventional VSI, but lag and manoeuver error are virtually eliminated.: Note: Even the normal VSI will indicate almost immediate trend info, but only the IVSI will indicate an accurate immediate rate of climb or descent. For example when establishing a climb, the normal VSI will at least indicate "some degree of climb': but will not give you precise info if it is 100 ft/min or 500 ft/min (it will, but you can not rely on it). The IVSI wilt not only give you trend, but will immediately show you the accurate rate

73- The vertical speed indicator VSI is fed by: A) differential pressure. B) total pressure. C) dynamic pressure. D)static pressure.

74- A vertical speed indicator measures the difference between:

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A) the dynamic pressure and the static pressure. B) the total pressure and the static pressure. C) the total instantaneous pressure and the total pressure at a previous moment. D)the instantaneous static pressure and the static pressure at a previous moment.

75- If the static intakes are completely clogged up by ice during a climb, the VSI shows:

A) a descent if the outside static pressure is less than the pressure in the VSI-gauge. B) zero. C) a constant rate of climb, even if the aircraft is levelling out. D)an increasing rate of climb if the ambient static pressure decreases.

76- If the static source of a Vertical Speed Indicator (VSI) becomes blocked during a climb the instrument will:

A) indicate a height equivalent to the setting on the millibar subscale. B) gradually indicate zero. C) under-read, D)continue to display the reading at which the blockage occurred.

77- What happens when the static pressure supply, to a Vertical Speed Indicator. becomes blocked during a descent?

A) Reading gradually reduces to zero. B) Over-reads. C) Under-reads. D)Indicates altitude at which blockage occurred.

78- What is the principle of operation of a VSI?

A) Differential pressure across a capsule. B) Total pressure in a capsule, C) Static pressure in a capsule. D)Dynamic pressure in a capsule.

79- The Vertical Speed Indicator (VSI) gives:

A) immediate trend information and immediate climb or descent information. B) immediate trend information and stable climb or descent information after 6 to 12

seconds (depending or type). C) no trend information, but stable climb or descent information after 6 to 12 seconds

(depending on type). D)immediate stable climb or descent information, but unreliable trend information.

80- ,Within a temperature range of +50 °C and -20 °C the VS/ is accurate to within limits of:

A) ± 200 ft/min B) ± 0 ft/min C) ± 30 ft/min

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D)± 300 ft/min The VSI should be checked during a preflight inspection, especially prior to an instrument flight. When performing a ground check of your VSI, obviously you want to see that the VSI needle is indicating a "zero" rate of climb/descent. If an error is discovered, it should be noted and then factored in during the flight (all readings adjusted by this error). This is of course only if the error is within acceptable tolerance limits. There are: • ± 200 ft per minute at temperatures from -20 DC to +50 DC •± 300 ft per minute at other temperatures 81- The vertical speed indicator reads:

A) the differential pressure between the capsule pressure and the case pressure. B) the differential pressure between the capsule pressure

and the outside static pressure. C) the differential pressure between the static pressure , . and pitot pressure. D) only the outside static pressure

82- Which statement is correct tor the Vertical Speed indicator (VSI) during a climb?

A) The pressure inside the capsule equalises the pressure inside the case. B) The pressure inside the capsule drops faster than the pressure inside the case. C) The pressure inside the case drops faster than the pressure inside the capsule. D) The pressure inside the capsule drops slower than the pressure inside the case.

83- Assume aircraft with pressurized cabin in flight. When switching to the alternate static pressure source, the pointer of the Vertical Speed Indicator:

A) does not move. S) indicates a climb, then maintains this position. C) indicates a climb, then settles down and reads correctly. D) indicates a climb, then settles down and reads incorrectly.

Some aircraft are equipped with an alternate source of static pressure for the pitot-static instruments in case the main source of static pressure becomes blocked - for example by ice. On unpressurized aircraft this alternate static source typically takes the static pressure from the cabin of the aircraft. On pressurized aircraft, there would be no point in the source being inside the cabin, where the pressure is diametrally different from the outside pressure - therefore the alternate static source is external, located at a different location than the normal static pressure port. The normal static pressure port will be always located at the best suitable location on the airframe (to

, get the most precise instrument readings), therefore the alternate source will have to be located at a less optimum location (no point in placing them in the same location if we want to have redundancy). Typically, this less optimum location will suffer from various forms of air turbulence caused by different airframe parts and/or different flight attitudes => the static pressure sensed here will be typically slightly lower as a result of the airflow disturbance. Lower pressure means a higher altitude in the "minds" of pitot-static instruments =:> hence the VSI will initially indicate a climb during the switch-over to the alternate static source, then as the static pressure settles the VSI comes back to zero and subsequently will operate, but not as accurately as with the normal static source (the alternate static source will be subject to pressure disturbances from airframe components and/or flight attitudes).

84- VFE is the maximum speed: A) with the flaps extended for each approved flap position.

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B)with the flaps extended in landing position. C).at which the flaps can be operated in turbulence. D)with the flaps extended in takeoff position.

(Refer to figures 022-E45 and 022-E46) • White arc - extends from VSD (stall full flap) to VFE (maximum speed with flaps extended) and marks

the flap operating range. • Green arc - from VS1 (stall clean) to VNO (normal operating speed).

This is the normal operating range of speeds. ,

• Yellow arc - from VNO to VNE (never exceed speed). This denotes the "use with caution" range (or

sometimes called the "structural warning range'). It should not be used in conditions other than smooth air. ' • Red line - marks VNE • Blue line - is used only on light multi-engine aircraft and marks V YSE = best rate of climb single-engine.

Notes: • The speed VFE is determined for each approved flap position. For example on a B737-300 the VFE for

flaps 1 = 230 kts, VFE for flaps 5 = 225 kts, flaps 10 = 210 kts, flaps 15= 195 kts, etc. • VNO is the acronym for Maximum Normal Operating Speed (or Maximum Structural Cruising Speed)

and refers to the maximum speed not to be exceeded except in still air and with caution. Do not confuse this with the VNE which is the never exceed speed (red line) or VMO (Maximum Operating Limit Speed).

85- VLE is the maximum: A) speed at which the landing gear can be operated with

full safety. B) flight speed with landing gear down. C) speed with flaps extended in a given position. D) speed authorized in flight.

(Refer to figures 022-E45 and 022-E46)

• Landing gear Operating speed (VLO) - the maximum speed for extending or retracting the landing

gear if using an airplane equipped with retractable landing gear.

Landing gear Extended speed (VLE) - the maximum speed at which an airplane can be safely flown with the landing gear extended

86- VNO is the maximum speed: A) which must never be exceeded. B)not to be exceeded except in still air and with caution. C) at which the flight controls can be fully deflected. D)with flaps extended in landing position.

87- A pitot blockage of both the ram air input and the drain hole with the static port open causes the airspeed indictor to:

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A) react like an altimeter. B) read a little high. C) read a little low. D) freeze at zero.

88-In a standard atmosphere and at the sea level, the calibrated airspeed (CAS) is: A) higher than the true airspeed (TAB). B) independent of the true airspeed (TAS). C) equal to the true airspeed (TAS). D) lower than the true airspeed (TAS).

(Refer to figures 022-E45 and 022-E46) Indicated airspeed (IAS) = the direct instrument reading obtained from the ASI, uncorrected for variations in atmospheric density, installation error, or instrument error. IAS drops as you climb, because as the density of the air decreases with altitude, fewer air molecules hit the pitot tube. This effect is most noticeable in high-performance aircraft that operate at high altitude. For example, at cruise altitude, the airspeed indicator on the B737 may indicate about 280 kts when the actual speed through the air is more than 400 knots. Pilots use indicated airspeed to get the proper performance from their aircraft (takeoff, climb, approach, and landing speeds are based on IAS). Calibrated airspeed (CAS) = IAS corrected for position (pressure) and instrument errors (at certain airspeeds and with certain flap settings, the position and instrument errors may total several knots). This error is generally greatest at low airspeeds. In the cruising and, higher airspeed ranges, indicated airspeed and calibrated airspeed are approximately the same. Refer to the airspeed calibration chart to correct for possible airspeed errors.

Equivalent airspeed (EAS) == the speed at sea level that would produce the same incompressible dynamic pressure as the TAS at the altitude at which the vehicle is flying. An aircraft in forward flight is subject to the effects of compressibility. Likewise, the calibrated airspeed is a function of the compressible impact pressure. EAS, on the other hand, is a measure of airspeed that is a function of incompressible dynamic pressure. Structural analysis is often in terms of incompressible dynamic pressure, so that equivalent airspeed is a useful speed for structural testing. At sea level, standard day, CAS and EAS are equal (or equivalent), but only under those condition. EAS is CAS corrected for compressibility error. The ASI over-reads due to compressibility error ==> the correction will be subtracted from CAS to obtain EAS ==> EAS is always lower than or equal to CAS. True airspeed (TAS)= CAS corrected for altitude and non-standard temperature. It is the actual speed of an aircraft through the air. Because air density decreases with an increase in altitude, an airplane has to be flown faster at higher altitudes to cause the same pressure difference between pitot impact pressure and static pressure. Therefore, for a given CAS, the TAS increases as altitude increases; or for a given TAS, the CAS decreases as altitude increases. The airspeed indicator displays TAS only at sea level under standard conditions, so you must calculate TAS based on IAS, the current pressure altitude. and air temperature. As a rule of thumb, you can estimate TAS by adding 2% to IAS for each 1.000 ft of altitude. Pilots use TAS in navigation calculations and when filing flight plans. Ground speed (GS) = the actual speed of the airplane over the ground. It is true airspeed adjusted for Wind. Ground speed decreases with a headwind, and increases with a tailwind. Summary: CAS == IAS + Pressure error correction EAS == CAS + Compressibility error correction TAS == EAS + Density error correction

TAS= CAS + Compressibility error correction + Density Error correction

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89- VLO is the maximum: A) flight speed with landing gear down. B) speed at which the landing gear can be operated with full safety. C) speed with flaps extended in a given position. D) cruising speed not to be exceeded except in still air with caution.

90- The limits of the green scale of. an airspeed indicator are: A) VS1 for the lower limit and V NE for the upper limit. B) VSO for the lower limit and V NO for the upper limit. C) VS1 for the lower limit and V NO for the upper limit. D) VS1 for the lower limit and VLO for the upper limit.

91- The limits of the yellow scale of an airspeed indicator are: A) V FE for the lower limit and V NE for the upper limit. B) V LO for the lower limit and V NE for the upper limit. C) V LE for the lower limit and V NE for the upper limit. D) V NO for the lower limit and V NE for the upper limit.

92- The calibrated airspeed (CAS) is obtained by applying to the indicated airspeed (IAS):

A) an instrument and density correction. B) an antenna and compressibility correction. C) an instrument and position/pressure error correction. D) a compressibility and density correction.

93-Wben descending through an isothermal layer at a constant calibrated airspeed (CAS), the true airspeed (TAS) will:

A) increase at a linear rate. B) decrease. C) increase at an exponential rate. D) remain constant.

Calibrated airspeed (CAS) =IAS corrected for position (pressure) and instrument errors (at certain airspeeds and with certain flap settings, the position and instrument errors may total several knots). This error is generally greatest at low airspeeds. In the cruising and higher airspeed ranges, indicated airspeed and calibrated airspeed are approximately the same. Refer to the airspeed calibration chart to correct for possible airspeed errors. True airspeed (TAS)= CAS corrected for altitude and non-standard temperature. It is the actual speed of an aircraft througl7 the air. Because air density decreases with an increase in altitude, an airplane has to be flown faster at higher altitudes to cause the same pressure difference between pitot impact pressure and static pressure. Therefore, for a given CAS, the TAS increases as altitude increases; or for a given TAS, the CAS decreases as altitude increases. The airspeed indicator displays TAS only at sea level under standard conditions, so you must calculate TAS based on IAS, the current pressure altitude, and air temperature. As a rule of thumb, you can estimate TAS by adding 2% to IAS for each 1.000 ft of altitude. Pilots use TAS in

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navigation calculations and when filing flight plans.

We need to keep in mind that the density of the atmosphere becomes less as we climb higher and the opposite is true when we descend. The speed displayed on the ASI (Air Speed Indicator) is proportional to the dynamic pressure » Po (also called the ram air pressure). Po is the extra pressure exerted when an object moves through the air (it is actually the resistance of the. air to that movement). Thus, PD increases with increased speed of the object and with increased density of the air. In order to maintain a constant CAS, the TAS must be decreased. Therefore, in a descent through an isothermal layer at constant CAS, TAS decreases and during a climb at constant CAS, TAS increases

94- With a pitot probe blocked due to ice buildup, the aircraft airspeed indicator will indicate in descent a:

A) decreasing speed. B)constant speed. C) increasing speed. D) f1uc;tuating speed.

95- With a pitot probe blocked due to ice buildup, the aircraft airspeed indicator will indicate in descent a:

A)decreasing speed. B)constant speed. C) increasing speed. D) f1uctuating speed.

96-The airspeed indicator circuit consists of pressure sensors. The pitot tube directly supplies:

A) the total pressure. B) the total pressure and the static pressure. C) the static pressure. D) the dynamic pressure.

'(Refer to figures 022-E45 and 022-E46) An aircraft stationary on the ground is subject to normal atmospheric or static pressure, which acts equally on all parts of the aircraft structure. In flight the aircraft experiences an additional pressure on its leading surfaces, due to a buildup of the air through which the aircraft is travelling. This additional pressure, due to the aircraft's motion, is known as Dynamic pressure and is dependent upon the forward motion of the aircraft and the density of the air. Therefore, the frontal parts of the airframe, including the front opening of the pitot tube are subject to both Static + Dynamic pressure, which as a summary make up a Total pressure (or sometimes referred to as the "impact pressure"), according to the following formula: PT=1/2 pV2 + Ps' where Pt= Total Pitot Pressure (also known as total head pressure or stagnation pressure); PS = static pressure; p (rho)= air density; V=velocity of aircraft. Re-arranging the formula, the difference between the Total and Static pressures is equal to ½ pV2 (Dynamic pressure). The airspeed indicator measures this pressure differential and provides an indication graduated in units of speed. When we simplify the above formula, we get PT=PD + PS' because PD=1/2p'V2 97- If the static source to an airspeed indicator (ASI) becomes blocked during a descent the instrument will:

A) under-read. B)read zero.

C)continue to indicate the speed applicable to that at the time of the blockage.

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D) over-read.

98- VNE is the maximum speed:

A) at which the flight controls can be fully deflected. B} not to be exceeded except in still air and with caution. C) which must never be exceeded. D) with flaps extended in landing position.

99-For a constant calibrated airspeed (CAS) and a level flight, a fall in ambient temperature will result in a:

A) lower true airspeed (TAS) due to an increase in air density. B) higher true airspeed (TAS) due to a decrease in air density. C) higher true airspeed (TAS) due to an increase in air

density. . D) lower true airspeed (TAS) due to a decrease in air density.

Calibrated airspeed (CAS) = IAS corrected for position (pressure) and instrument errors (at certain airspeeds and with certain flap settings, the position and instrument errors may total several knots). This error is generally greatest at low airspeeds. In the cruising and higher airspeed ranges, indicated airspeed and calibrated airspeed are approximately the same. Refer to the airspeed calibration chart to correct for possible airspeed errors. True airspeed (TAS) = CAS corrected for altitude and non-standard temperature. It is the actual speed of an aircraft through the air. Because air density decreases with an increase in altitude, an airplane has to be flown faster at higher altitudes to cause the same pressure difference between pitot impact pressure and static pressure. Therefore, for a given CAS, the TAS increases as altitude increases; or for a given TAS, the CAS decreases as altitude increases. The airspeed indicator displays TAS only at sea level under standard conditions, so you must calculate TAS based on IAS, the current pressure altitude, and air temperature. As a rule of thumb, you can estimate TAS by adding 2% to IAS for each 1.000 ft of altitude. Pilots use TAS in navigation calculations and when filing flight plans. The speed displayed on the ASI (Airspeed Indicator) is proportional to the dynamic pressure, Po (also called the ram air pressure). Po is the extra pressure exerted on an object when it moves through the air (it is actually the resistance of the air to that movement). Thus, Po increases with increased speed of the object and with increased density of the air (PD = 1/2 p'V2). Temperature & density are inversely proportional => a decrease in temperature implies an increase in air "density. In order to maintain a constant CAS (Which does not take into account the increase in density) - i.e. constant Po' the TAS (i.e. the speed V from the formula) must be decreased (see formula above). Therefore, for a constant CAS and a level flight, a fall in temperature will result in a lower TAS due to an increase in air density and a rise in temperature will result in a TAS increase

100-A leak in the pitot total pressure line of a non-pressurized aircraft to an airspeed indicator would cause it to:

A) over-read. B) under-read. C) indication will drop to zero. D) freeze on the value it indicated at the time of failure.

If there is a leak in the pitot line of a non-pressurized aircraft, the total pressure (PT) sensed by the

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pitot tube will decrease (assuming the true speed is constant and thus the dynamic pressure-PD is constant). Static pressure (PS) remains constant (assuming it's a straight and level flight). The way the airspeed indicator (ASI) derives speed information is P T - P s = PD.

PD is the dynamic pressure and it is proportional to the speed. The higher the speed the higher the PD . It is basically the PD that is indicated the ASI. With PS information constant and PT information being lower than actual due to the leak, the dynamic pressure PD will also be lower than actual (because PD=PT - PS).The ASI displays the speed information using the formula PD = 1/2p'V2; therefore, if PD is lower than actual, then the speed will also read lower than actual => the ASI under-reads

101- The limits of the white scale of an airspeed indicator are: A) V so for the lower limit and V FE; for the upper limit. B) V S1 for the lower limit and V LE; for the upper limit. C) VSO for the lower limit and VLE for the upper limit. D) VS1 for the lower limit and V FE for the upper limit.

102- During a climb after takeoff from a contaminated runway if the total pressure probe of the airspeed indicator i: blocked, the pilot finds that indicated airspeed:

A) decreases. abruptly towards zero. B) increases steadily. C) increases abruptly towards V NE. D) decreases steadily.

103- Calibrated airspeed is:

A) IAS plus the pressure error only. B) IAS plus density error correction. C) IAS plus compressibility correction. D) IAS plus instrument error correction.

104- Assume non-pressurized aircraft. A leak in the pressure line from the pitot tube will affect the airspeed indicate in the following way:

A) under-read. B) over-read. C) over-read in a climb and under-read in a descent. D) under-read in a climb and over-read in a descent.

105- A blocked pitot head with a clear static source causes the airspeed indicator to: A) read like a vertical speed indicator. B) react like an altimeter. C) operate normally. D) freeze at zero.

106- An airspeed indicator displays: A) IAS B) EAS C) CAS D) TAS

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107- An airspeed indicator includes a capsule; inside this capsule is: A) a very low residual pressure and outside is static pressure. B) static pressure and outside is dynamic pressure. C) dynamic pressure and outside is static pressure. D)total pressure and outside is static pressure.

(Refer to figures 022-E45 and 022-E46) An aircraft stationary on the ground is subject to normal atmospheric or static pressure, which acts equally-on all parts of the aircraft structure. In flight the aircraft experiences an additional pressure on its leading surfaces, due to a buildup of the air through which the aircraft is travelling. This additional pressure, due to the aircraft's motion, 'is known as Dynamic pressure and is dependent upon the forward motion of the aircraft and the density of the air. Therefore, the frontal parts of the airframe, including the front opening of the pitot tube are subject to both Static + Dynamic pressure, which as a summary make up a Total pressure (or sometimes referred to as the "Impact pressure"), according to the following formula: PT = 1/2 pV2 + Ps' where PT = Total Pitot Pressure (also known as total head pressure or stagnation pressure); P s = Static pressure; p = (rho) air density; V = velocity of aircraft. Re-arranging the formula, the difference between the Total and Static pressures is equal to 1/2 pV2 (Dynamic pressure). The airspeed indicator measures this pressure differential and provides an indication graduated in units of speed. When we simplify the above formula, we get PT = PD + Ps' because PD = 1/2 Pv2, In the Airspeed Indicator (ASI), a capsule acting as the pressure sensitive element is mounted in an airtight case. Pitot pressure (total pressure) is fed into the capsule and static pressure is fed to the interior of the case which, when the aircraft is in motion, thus contains the lower pressure. A pressure difference will cause the capsule to open out with movement proportional to pressure differential across the capsule skin (pitot - static). A mechanical link is used to transfer the capsule movement to a pointer moving around a dial calibrated in knots. A bimetallic strip is incorporated in the mechanical linkage to compensate for expansion/contraction of the linkage due to temperature variation. In the sensitive ASI, which reacts to smaller pressure changes, we use a stack of two or more interlinked capsules connected to the pointers by an extended gear train. Which provides indications of smaller changes in airspeed. Remember: Total pressure = inside of the capsule; Static pressure = outside of the capsule (in the instrument case).

108- Assuming that the CAS remains constant, if the total pressure probe is blocked, the IAS;

A) remains constant during level flight, decreases during a climb and increases during a descent. B) remains constant during level flight, increases during a climb and decreases during a descent: C) increases during level flight, remains constant during a climb and a descent.

D) remains constant during all the phases of the flight.

109- Calibrated airspeed (CAS) is obtained from indicated airspeed (IAS) by correcting for the following errors: 1)position 2) compressibility 3) instrument 4) density The combination regrouping all the correct statements is:

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A) 2,3,4 B) 3,4 C) 1.3,4 D) 1,3

110- Calibrated airspeed (CAS) is obtained from indicated airspeed (IAS) by correcting for the:

A) instrument error. B) position and instrument errors. C) density error. D) position and density errors.

111- Calibrated airspeed (CAS) is:

A) indicated airspeed (IAS) corrected for compressibility error. B) indicated airspeed (IAS) corrected for position and instrument errors. C) equivalent airspeed (EAS) corrected for density error.

D)equivalent airspeed (EAS) corrected for compressibility and density errors.

112- CAS can be obtained from the following data: A) TAS and pressure altitude. B) EAS and density altitude. C) EAS and pressure altitude, D) TAS and density altitude.

113- Concerning the airspeed indicator, IAS is:

A) . the indicated reading on the instrument. B) the indicated reading on an instrument presumed to be perfect.

C) the indicated airspeed corrected for instrument and position errors. D)the indicated airspeed corrected for instrument error only.

114- Considering the relationship between CAS and EAS: A) EAS may be lower or greater than CAS, depending on density altitude. B) EAS is always greater than or equal to CAS. C) EAS may be lower or greater than CAS, depending on pressure altitude.

D)EAS is always lower than or equal to CAS.

115-During a climb, the total pressure probe of the airspeed indicator becomes blocked; if the pilot tries to maintain a constant indicated airspeed, the true airspeed:

A) increases until reaching VMO. B) decreases until reaching the stall speed. C) decreases by 1% per 600 ft. D) increases by 1% per 600 ft.

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(Refer to figure 022-E51)

A blocked pitot tube (total pressure probe) is a pitot-static problem that will only affect airspeed indicators. Pitot tube senses a total pressure. A blocked pitot tube will cause the airspeed indicator to incorrectly display an increase in airspeed when the aircraft climbs, even though the actual airspeed is constant. This is caused by the total pressure in the pitot system remaining constant (held constant by the blockage at a value at which the blockage occurred) and at the same time the atmospheric pressure (static pressure) decreasing due to the aircraft climbing => this will produce a greater difference between the total and static pressures, which will be indicated by the airspeed indicator as an increased speed. Therefore, if the pilot is unaware of the problem, then as the aircraft is climbing the airspeed indicator (ASI) will be indicating higher indicated airspeed => the pilot will try to pull-up a bit more in an attempt to lower the speed, therefore increase the climb rate and further increase the indicated airspeed => pulling back on the yoke even more. All this time the actual speed will be getting lower and lower, without the pilot knowing, until the stall warning alert will sound

116-During descent, the total pressure probe of the airspeed indicator becomes blocked. In this case: 1)IAS becomes greater than CAS. 2)IAS becomes lower than CAS. 3)Maintaining IAS constant, VMO may be exceeded. 4)Maintaining IAS constant, aircraft may stall.

The combination regrouping all the correct statements is A) 2,4 B) 2,3 C) 1,3 D) 1,4

(Refer to figure 022·E51) A blocked pitot tube (total pressure probe) is a pitot-static problem that will only affect airspeed indicators. Pitot tube senses a total pressure. A blocked pitot tube will cause the airspeed indicator to incorrectly display an decrease in airspeed when the aircraft descends, even though the actual airspeed is constant. This is caused by the total pressure in the pilot system remaining constant (held constant by the blockage at a value at which the blockage occurred) and at the same time the atmospheric pressure (static pressure) increasing due to the aircraft descending => this will produce a smaller difference between the total and static pressures, which will be indicated by the airspeed indicator as an increased speed. The pilot, if unaware of the situation, will therefore {try to increase the indicated airspeed. This will only increase the a dual airspeed to the point that V MO can be exceeded without the pilot even knowing

117-Equivalent airspeed (EAS) is obtained from calibrated airspeed (CAS) by correcting for the following errors: 1)position 2)compressibility 3)instrument 4)density

The combination regrouping all the correct statements is A) 2,4 B) 4 C) 2 D) 1,2,3,4

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118- Equivalent airspeed (EAS) is obtained from calibrated airspeed (CAS) by correcting for:

A) compressibility error .. B) position error. C) instrument error. D)density error.

119- Equivalent airspeed (EAS) is obtained from indicated airspeed (IAS) by correcting for the following errors: 1)instrument 2)position 3)density 4)compressibility

The combination regrouping all the correct statements is: A) 1,2,3 B)1,2,4 C) 1,2 D) 1,2,3,4

120- Equivalent airspeed (EAS) is:

A) true airspeed (TAS) corrected for compressibility error. B) indicated airspeed (IAS) corrected for compressibility error. C) calibrated airspeed (CAS) corrected for density error. D)indicated airspeed (IAS) corrected for position. instrument and compressibility errors.

. 121- Equivalent airspeed (EAS) is:

A) calibrated airspeed (CAS) corrected for compressibility error. B) calibrated airspeed (CAS) corrected for density error. C) true airspeed (TAS) corrected for compressibility error. D) true airspeed (TAS) corrected for compressibility and density errors

122- Given:

P T = total pressure Ps = static pressure P so = static pressure at sea level Calibrated airspeed (CAS) is a function of:

A) PT - Ps B) PT – PSO C) PT -PS D) (PT – PSO) /Ps

123- Given: PT = total pressure PS = static pressure

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P D = dynamic pressure The airspeed indicator is fed by:

A) PS- PT B)PD C)PT-PD D)PD-PS

124- If the total pressure intake on the pitot tube is rapidly clogged up by ice during flight, what effect will it have on the airspeed indication during a climb?

A) The total pressure is trapped while the static pressure decreases, implying an increasing indicated airspeed.

B) The total pressure is trapped while the static pressure decreases, implying a decreasing indicated airspeed.

C)As the total pressure in the pitot static system is trapped, the airspeed indicator will indicate a constant airspeed. D)The total pressure is trapped while the static pressure increases, implying a decreasing indicated airspeed.

125- If an aircraft maintaining a constant CAS and flight level is flying from a cold air mass into warmer air:

A) Mach number increases. B) TAs decreases. C) TAS increases.

D)Mach number decreases.

126- If an aircraft maintaining a constant CAS and flight level is flying from a warm air mass into colder air:

A) Mach number increases. B) TAS increases. C) TAS decreases. D) Mach number decreases.

127- If the pitot tube becomes blocked during a descent, the airspeed indicator: A) over-reads. B) under-reads. C) under-reads or over-reads, depending on the air density. D) indicates a constant speed.

128- In a standard atmosphere and at the sea level, the equivalent airspeed (EAS) is:

A) lower than the true airspeed (TAS). B) independent of the true airspeed (TAS). C) higher than the true airspeed (TAS). D) equal to the true airspeed (TAS).

129- In standard atmosphere, when descending at constant CAS:

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A) TAS remains constant. B) TAS decreases. C) TAs increases. D) TAS first increases and then remains constant below the tropopause.

130- In the absence of position and instrument errors, CAS is equal to: A) IAS B) EAS C) TAS D) IAS and EAS

131- In the absence of position and instrument errors, IAS is equal to: A) CAS and EAS B) EAs C) TAS D) CAS

132- In the absence of position and instrument errors: A) IAS = EAs B) IAS = CAS C) CAS = EAS D) CAS=TAS

133- Maintaining CAS and flight level constant, a fall in ambient temperature results in:

A) lower TAS because air density increases. B) lower TAS because air density decreases. C) higher TAS because air density increases. D)higher TAS because air density decreases.

134- TAS can be obtained from the following data: A) CAS and pressure altitude. B) EAS and pressure altitude. C) CAS and density altitude. D)EAS and density altitude.

135- The parameter that determines the relationship between EAS and TAS is: A) mach number. B) pressure altitude. C) OAT. D)density altitude.

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136- The pressure capsule of an airspeed indicator is sensitive to the difference: A) (Total Pressure - Dynamic Pressure), called Static Pressure. B) (Dynamic Pressure - Static Pressure), called Total Pressure. C) (Total Pressure - Static Pressure), called Dynamic Pressure. D)(Dynamic Pressure - Total Pressure), called Static Pressure.

137-True airspeed (TAS) is equal to equivalent airspeed (EAS) only if:

A) p =1013,25 hPa, OAT= 15°C and TAS < 200 kts. B) p = 1013,25 hPa and OAT= 2730 K. C) P = 1013,25 hPa, OAT=15°C and TAS > 200 kts. D)p = 1013,25 hPa and OAT=15°C.

138- True

1)instrument

airspeed (TAS) is obtained from calibrated airspeed (CAS) by correcting for the following errors:

2)compressibility 3)position 4)density

The combination regrouping all the correct statements is A)2,4 B) 2 C) 4 D) 1,2,3,4

139- True airspeed (TAS) is obtained from equivalent airspeed (EAS) by correcting for:

A) instrument error. B) Compressibility error. C) density error. D)position and instrument errors.

140- True airspeed (TAS) is obtained from indicated airspeed (IAS) by correcting for the following errors: 1)instrument 2)position 3)compressibility 4)density

The combination regrouping all the correct statements is: A)3,4 B)1,2,3,4 C) 1,2 D)1,3,4

141- True airspeed (TAS) is:

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A) equivalent airspeed (EAS) corrected for compressibility error. ~ B) equivalent airspeed (EAS) corrected for density error. C) calibrated airspeed (CAS) corrected for density error. D)calibrated airspeed (CAS) corrected for compressibility error.

142- True airspeed (TAS) is: A) calibrated airspeed (CAS) corrected for density error only. B) calibrated airspeed (CAS) corrected for compressibility and density errors. C) equivalent airspeed (EAS) corrected for compressibility error only. D)equivalent airspeed (EAS) corrected for compressibility and density errors.

143- True airspeed (TAS) is: A) calibrated airspeed (CAS) corrected for instrument, compressibility and density errors. B) indicated airspeed (IAS) corrected for compressibility and density errors only. C) calibrated airspeed (CAS) corrected for instrument, position, compressibility and density

errors. D) indicated airspeed (IAS) corrected for instrument, position, compressibility and density

errors.

144- When climbing at a constant CAS in a standard atmosphere:

A) TAS decreases. B) TAS increases. C) TAS remains constant D) TAS first decreases, then remains constant above the tropopause.

145- When climbing at .a constant CAS:

A) EAS decreases. B) EAS increases. C) EAS remains constant. D) EAS does not depend on altitude.

EAS (Equivalent Air Speed) is CAS corrected tor compressibility error (this means that CAS takes into account the compressibility in the standard atmosphere, at sea level and EAS takes into account the true compressibility). The ASI over-reeds due to compressibility error ::> the correction will be subtracted from CAS to obtain EAS :;> EAS is always lower than or equal to CAS. When descending, density increases and thus, the air becomes less compressible ::> compressibility effect will be reduced »> the correction value will be tower ::> EAS will increase. Using the same principle we can see that EAS decreases during a climb at a constant CAS.

146- When descending at a constant CAS: A) EAS increases. B) EAS decreases. C) EAS remains constant. D)EAS does not depend on altitude.

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147- With constant weight and configuration, an aircraft always takes off at the same:

A) indicated airspeed. B) ground speed. C) true airspeed. D)equivalent airspeed.

The takeoff speed is too small to have significant compressibility. Therefore, we can say that in this situation CAS::EAS ::> TAS is CAS corrected for density error. (CAS takes into account the density in standard. atmosphere, at sea level and TAS takes into account the true density). Density decreases with altitude 0::> at constant weight, the takeoff TAS varies with altitude, but the takeoff EAS (or CAS, because they are equal) remains the same irrespective of the airfield altitude. 148- With EAS and density altitude, we can deduce:

A) CAS and TAS B) CAS C) TAS

D) IAS

149- With EAS and pressure altitude, we can deduce: A)TAS B) CAS C) CAS and TAS D)IAS

150- The input connections to an airspeed indicator are from: A) a static source only. B) a pitot source only. C) both pitot and static sources. D)pitot and static sources and outside air temperature sensor.

.

151- The calibration for the ASI is based on density: A) at the normal cruising altitude. B) at the tropopause. C) at sea level, ISA temperature. D) at sea level, ISA +15 °C.

The airspeed indicator, like all other pitot-static instruments, is calibrated for the ISA conditions at sea level. Remember ,ISA conditions are 15 °C at sea level.

152- If the static pressure port iced over while descending from altitude, the airspeed indicator would read:

A) zero B) high C) low D)correctly

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153- The position error of an ASI results from: A) mechanical differences in individual instruments. B) the difference in air density from sea level ISA density. C) the effects of the airflow around the static vent and pitot head. D) the fact that air becomes more compressible at high speeds.

Instrument error» is caused by manufacturers' permitted tolerances in construction ot the instrument. The error is determined during calibration and a correction is combined with that for pressure error. Pressure (position) error - arises from movement of the air around the aircraft. This causes disturbances in the static pressure sensing (slightly turbulent air around the static port). Pressure error is tabulated in the aeroplanes flight manual and it increases with increase in speed of the aircraft. Compressibility error - the calibration formula for most airspeed indicators does not contain any compensation for the fact that the air is compressible. At IDW speeds this is insignificant but, at high speeds this factor becomes of importance. This is especially SD at high altitudes where the less dense air is easily compressed , compressibility causes an in increase in the measured value of dynamic pressure, which causes the ASI to over-reed. Thus, compressibility varies with speed and altitude. The error and correction can be compensated on some mechanical navigation computers but is tabulated against altitude, temperature and CAS in the pilot hand books . Density error-dynamic pressure varies with air speed and density of the air. In calibration, standard mean sea level pressure is used; thus, for any other condition of air density, the ASI will be in error. As altitude increases, density decreases and indicated air speed (IAS) and thus equivalent air speed (EAS) will become progressively lower than true air speed (TASJ- In practice, a correction for density is made using the navigation computer to convert CAS to TAS using arguments of altitude and outside air temperature.

154- CAS is IAS corrected for: A) position and instrument error. B) instrument, pressure and density error. C) relative density only. D) compressibility. 155- At constant weight, regardless of altitude, an aircraft always lifts off at a constant:

A) EAS B) TAS C) ground speed D) CAS

156- VFE is the maximum speed at which: A) the flaps can be operated. B)the flaps may be extended in the takeoff configuration. C) the flaps may be extended in the landing configuration. D) the flaps may be extended in a specified configuration.

157- The white arc on the ASI indicates:

A) V SI at the lower end and V LE at the upper end. B) V so at the lower end and V LE at the upper end. C) V so at the lower end and V FE at the upper end. D) VS1at the lower end and V FE at the upper end.

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158- An ASI circuit consists of pressure sensors. The pitot probe measures: A) total pressure and static pressure. B) dynamic pressure. C) static pressure. D) total pressure.

159- If a pitot source is blocked in an airspeed indicator (ASI), the drain hole is blocked, but the static source is open, what will happen? A) ASI reading goes to zero.

B) ASI under-reads C)ASI over-reads. D)ASI behaves like an altimeter.

160- VNO is the maximum speed which: A) the pilot can fully deflect the controls. B) should only be exceeded in still air and with caution. C) should never be exceeded. D) must not be exceeded for flap/gear extension.

161- If the pitot tube is leaking (and the pitot drain is blocked, in a non-pressurized A/C, the ASI will:

A) under-read. B) over-read.

C)over-read in the climb, under-read in the descent. D) under-read in the climb, over-read in the descent.

162- At sea level ISA. TAS: A) equals CAS. B) is greater than CAS. C) is less than CAS.

163- If a pitot tube and drains are blocked at altitude by icing, during a descent the airspeed indicator will:

A) read constant airspeed. B) under-read. C) over-read. D) show zero.

164- What are the upper and lower limits of the yellow arc on an ASI? A) Lower limit VLO and upper limit VNE,

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B) Lower limit V LE and upper limit V NE. C) Lower limit V NO and upper limit V NE. D) Lower limit VLO and upper limit VLE•

165- What happens when the static vent supplying an al; speed indicator (ASI) is blocked, and the ram air inlet remains clear?

A) ASI acts opposite to an altimeter. B) ASI always over-reads/reads a higher value. C) ASI always under-reads/reads a lower value. D) ASI acts like an altimeter.

166- VLO is defined as:

A) the maximum speed at which to fly with the landing gear retracted. B) the maximum speed at which the landing gear may be

retracted or extended. C) the maximum speed at which to fly with the landing gear extended.

D)the minimum speed at which to fly with the landing gear extended.

167- VNE is defined as: A) the speed which must not be exceeded in still air, or without caution.

B)the speed above which the landing gear may not be extended. C)the speed which must never be exceeded. D)the maximum speed for normal flap extension to be selected.

168- The green arc on the ASI is used to identify which speed range? A) VSO to VNO. B)VS1 to VFE. C) VS1 to VNO. D) VS1 to VLO.

169- VNO is defined as:

A) maximum structural cruising speed. B) never exceed speed. C) manoeuvering speed. D) maximum operating speed.

170- What is indicated on the airspeed indicator when the static vent blocks during a descent?

A) Under reads. B) Reads correctly. C) Over reads. D) Reads zero.

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171- What does the green arc on an ASI indicate?

A) VS1 - VNE B)VS1 - VLO C) VS1 - VNO D) VSO - VNO

172-During a climb, if the total pressure probe of the airspeed indicator is blocked, the indicated airspeed:

A) is underestimated. B) is overestimated. C) increases abruptly towards VNE.

D)decreases abruptly towards zero

173- The airspeed indicator is a differential manometer measuring the difference between:

A) the total pressure and the static pressure. B) the dynamic pressure and the static pressure. C) the static pressure and the dynamic pressure. D) the total pressure and the dynamic pressure.

174- The airspeed indicator measures: A) absolute pressure. B) total pressure. C) differential pressure. D) relative pressure.

175- What is the significance of the yellow arc in an airspeed indicator? A) Flap operating range. B) Never exceed range. C) Structural warning range. D) Normal operating range.

176- What corrections must be applied to indicated airspeed to produce true airspeed?

A) Correction for heading and altitude. B) Correction for wind and temperature. C) Correction for altitude and wind. D) Correction for altitude and temperature.

177- The upper airspeed limit of the green arc on the airspeed indicator represents: A) maximum structural cruising speed (V NO)'

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B) landing gear lowering speed (V LE)' C) design manoeuvering speed (VA)'

D)maximum allowable speed for smooth-air operations (VNE)·

178- The pitot tube supplies: A) alternate static pressure. B) impact pressure. C)dynamic pressure alone. D) static pressure alone.

179- In the air-tight instrument case of the airspeed indicator we will find:

A) Total pressure. B) Static pressure. C) dynamic pressure. D) ram air.

180- . If indicated airspeed is corrected for a positive error, the resulting calibrated airspeed will be:

A) lower. B) it will not be CAS but EAS. C) higher. D) it will not be CAS but TAS.

181- Indicated airspeed corrected for position error is:

A) equivalent air speed. B) true air speed. C) calibrated airspeed. D) ground speed.

182- As an airplane climbs higher, the true airspeed for a given indicated airspeed will:

A) be lower than indicated. B) the true airspeed and the indicated will be the same. C) decrease. D) increase.

183-Indicated airspeed (as read on the airspeed indicator) will:

A) increase in headwind. B) increase in tailwind. C) decrease in tailwind. D) remain unchanged in headwind and tailwind.

The aircraft flies within a mass of air, and the IAS at which it moves is independent of the movement of this mass of air. What will change is the ground speed. It is important to understand that the ground

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speed will not only fluctuate under gusty conditions but also depends upon the elevation of the airport due to the change in density altitude 184- When side-slipping, one of the instruments below will give an incorrect indication:

A) vertical speed indicator. B) altimeter. C) attitude indicator. D) airspeed indicator.

To provide the most accurate airspeed, the pilot tube must be aligned with the relative wind in order to receive accurate ram air pressure, which is not the case when you are side-slipping. Remember, that the airspeed indicator works with total pressure, dynamic pressure and static pressure. Other pitot-static instrument that use only the static pressure will not be so affected as the airspeed indicator which uses also the Pitot pressure (ram pressure). The reason is the fact that most aircraft, even small piston ones, have 2 static ports - one on each side of the fuselage. When side-slipping, the static pressure will increase on one side, but decrease on the other side, thus compensating each other and providing pretty much a correct static pressure source. It would be a different case with an aircraft that has only one static port or in the case where one of the two static ports was blocked for any reason (iced-up for example) - in that case all instruments would be effected. 185- Match calibrated airspeed (CAS) with the associated defi

A) calibrated airspeed corrected for altitude and non- nition:

standard temperature. B) actual speed of an aircraft over ground. C) the airspeed you read from the airspeed indicator. D) indicated airspeed corrected for installation and instrument errors.

186- Match true airspeed (TAS) with the associated definition:

A) the airspeed you read directly from the airspeed indicator. B) calibrated airspeed corrected for altitude and nonstandard temperature. C) actual speed of an aircraft over ground. D) indicated airspeed corrected for installation and instrument errors.

187- Match ground speed (GS) with the associated definition:

A) indicated airspeed corrected for installation and instrument errors. B) calibrated airspeed corrected for altitude and nonstandard temperature. C) actual speed of an aircraft over ground. D) the airspeed you read directly from airspeed indicator.

188- It. when correcting an EAS value of 150 kts, a TAS value of 146 Ids is obtained:

A) an error must have been made in the calculation. B) no allowance has been made for compressibility. C) the density of the atmosphere must be greater than the ISA mean sea level air density . D) no allowance has been made for position error.

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EAS (Equivalent Air Speed) is CAS corrected for compressibility error (this means that CAS takes into account the compressibility in the standard atmosphere, at sea level and EAS takes into account the true compressibility). The ASI over-reads due to compressibility error => the correction will be subtracted from CAS to obtain EAS => EAS is always lower than or equal to CAS. The CAS = IAS corrected for position (pressure) and instrument errors. This question is pointing out the fact that when aircraft operates in an atmosphere of greater density than standard (low altitude or cold weather) the TAS will actually be lower than the EAS. Most of the time, TAS is higher than EAS because aircraft fly at altitude, where density is lower than standard. As the temperature or altitude increases, the air density will decrease and this will cause the IAS to read lower than the TAS. At sea level on a 15°C day, IAS will be the same as TAS. As altitude increases, the difference between TAS and CAS will increase. At 10.000 ft at -5 "C, 250 knots IAS will give you about 290 knots TAS; at 20.000 ft at -25° C, 250 knot IAS will give you 335 knots TAS; at 30.000 ft and -45 "C, 250 knots IAS will give you about a 395 knot TAS. A good rule of thumb to approximate the difference between IAS and TAS is a 2% difference per 1.000 ft increase in altitude.

189- TAS is:

A) ground speed. B)the reading on the ASI. C)the aircraft's true airspeed which is EAS corrected for altitude and temperature. D) true airspeed of the aircraft which is RAS corrected for altitude and temperature.

190- The magnetic heading can be derived from the true heeding by means of a: A) map showing the isoclinic lines. B) map showing the isogonal lines. C) deviation correction curve. D) compass swinging curve.

The Magnetic North Pole and the True North Pole are not at the same location on the surface of the earth. Magnetic poles are continually changing position by a small amount and at any point on the earth's surface the field is not constant, being subject to changes both periodic and Irregular. In a similar manner, as meridians and parallels are constructed with reference to the geographic (true) poles, so magnetic meridians and parallels may be plotted with reference to the magnetic poles. If a map were prepared showing both true and magnetic meridians, it would be seen that the meridians intersect each other at angles varying at different points on the earth's surface. The horizontal angle contained between the True and Magnetic meridians at any place when looking north is known as magnetic variation. In short, the Variation is the angle between the True North and Magnetic North. Magnetic Variation is expressed as "at how many degrees East or West is the Magnetic North situated from the True North". Information regarding magnetic variation and its changes is printed on special charts of the World, which are issued every few years. The lines, drawn on the chart, joining places that have" the same value of variation are called "isogonals" or "isogonal lines"; those drawn through places which have zero variation are known as "agonic" lines. Isogonal lines are also found on navigation charts and allow the pilot to calculate Magnetic headings from True headings and vice versa.

191- True heading can be converted into magnetic heading using:

A) a map with isogonal lines. B) a map with isoclinal lines. C) a deviation card. D)a deviation curve.

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192- In the vicinity of the Magnetic North Pole the magnetic compass is useless because:

A) the magnetic field is too strong. B) the magnetic pole is moving. C) the horizontal component of the magnetic field is too weak. D) the variation is too large.

The lines of force in the Earth's magnetic field pass through the center of the Earth, exit at both magnetic poles, and bend around to re-enter at the opposite pole. Near the equator, these lines become almost parallel to the surface of the Earth. However, as they near the poles, they tilt toward the Earth until in the immediate area of the magnetic poles they dip rather sharply into the Earth (they are almost vertical). Because the poles of a compass tend to align themselves with the magnet lines of force, the magnet within the compass tends to tilt or "dip" toward the Earth in the same manner as the lines of force.

The magnetic compass measures the horizontal component of the magnetic field, which as explained in the paragraph above, is too weak near the pole to provide reliable information - the vertical component of the magnetic field Is the predominating one in the magnetic polar region.

193- Variation is defined as the angle between: A) MN and CN. B) TN and CN. C) TN and MN. D) CN and the longitudinal axis of the aircraft.

For explanation refer to question #5605 on this page. 194-The purpose of a compass swing is to attempt to coincide the indications of:

A) compass north and True North. B) compass north and Magnetic North. C) True North and Magnetic North. D)compass north and the lubber line.

(Refer to figure 022-E14)

The needle of a compass indicates the direction of the Magnetic North only when not influenced by other magnetic forces. Therefore, when;,) compass is installed in the cockpit of an aircraft, where it is subject to various forms of aircraft magnetism created by the airframe structure itself, electrical equipment in the aircraft, etc ... it Is not able to indicate the direction of Magnetic North precisely. Instead, it indicates a direction towards a so called "Compass North". It is the inaccurate direction of Magnetic North when the compass is being affected by other magnetic forces. A magnetic deviation is the angle between the Magnetic North and this incorrectly indicated Magnetic North - the Compass North. In other words. it is the a between the compass indication and the correct Magnetic meridian. Magnetic deviation is the difference between the compass indications when installed in the aircraft compared to the indications when the compass is outside the aircraft (free from disturbing magnetic forces of the aircraft). Deviation is stated as Easterly or Westerly, depending whether the North seeking section of the compass needle incorrectly swings towards the East or West of the correct Magnetic meridian when being affected by the aircraft magnetism.

As mentioned above, the compass needle is affected when aircraft electrical equipment is operated and by the ferrous metallic components within the aircraft. These internal magnetic fields tend to deflect the compass needle from its alignment with the Magnetic north. This tendency is called Deviation. Deviation varies, depending upon which electrical components are in use. The aircraft magnetic fields may also change as a

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result of mechanical jolts to the aircraft, from the installation of additional or different radio, equipment, or major mechanical work on an engine such as changing of the crankshaft or propeller. The crankshaft and the propeller are particularly susceptible to changes in inherent magnetism because they rotate in various magnetic fields. To reduce the effects of this deviation, the aircraft compass must be. checked and compensated periodically by adjusting the compensating magnets. This procedure is called "swinging the compass". During compensation (the compass swing), the compass is checked at 3D" increments. Adjustments are made at each of these points, and the difference between magnetic heading and compass heading is shown on a compass correction card (or called the Compass Deviation Card). When flying compass headings, the pilot must refer to this card and make the appropriate adjustment for the desired heading. To preserve accuracy, the pilot must ensure that no metallic objects such as flashlights or sunglasses are placed near the compass because they may induce additional significant errors

195- The purpose of compass swinging is to determine the deviation of a magnetic compass:

A) on a given heading. B) on any heading. C) at any latitude. D) at a given latitude.

196-The quadrantal deviation of a magnetic compass is corrected by using: A) magnetized needles. B) hard iron pieces. C) soft iron pieces. D) pairs of permanent magnets.

The majority of mechanical compass deviation compensation devices consist of two pairs of magnets, each pair being fitted into a bevel gear assembly made of non-magnetic material. The gears are mounted one above the other. This compass compensation device is referred to as the "micro-adjuster". In the neutral position, one pair of magnets is parallel to the aircraft's fore and aft axis for correction of co-efficient C, while the other pair lies athwartships to correct for coefficient B. By use of the compass correction key, a small bevel pinion may be turned, thus rotating one pair of bevel gears => the pairs of magnets are thus made to open, creating a magnetic field between the poles to deflect the compass needle and correct for co-efficient B or C, depending which pair of magnets are used. The micro-adjuster unit is normally mounted below the compass needle assembly in the "P" type direct reading compass and above the needle assembly in compass of the "E" series. Electrical Compensation - the exact design and construction of the electro-magnetic compass deviation compensator depends on the compass manufacturer. However, they all follow a similar concept whereby two variable potentiometers are connected to the coils of the flux detector unit. The potentiometers correspond to the co-efficient Band C magnets of a mechanical compensator and, when moved with respect to calibrated dials, they insert very small DC signals into the flux detector coifs. The magnetic fields produced by the signals are sufficient to oppose those causing deviations and accordingly modify the output from the detector head via the synchronous transmission link to drive the gyro and hence the compass heading indicator to show corrected readings.

Note: the detector units of remote indicating magnetic compasses also have means for deviation compensation. It is achieved mechanically or electrically (not electronically as this would imply a direct modification of the output signals, which is not the case) using the concepts described above. A deviation compensation device is typically mounted on top of the detector unit

197- The quadrantal deviation of the magnetic compass is due to the action of:

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A) the hard iron pieces and the soft iron pieces influenced by the hard iron pieces.. B)the soft iron pieces influenced by' the geomagnetic field.

C) the hard iron pieces influenced by the geomagnetic field. D) the hard iron pieces influenced by the mild iron pieces.

Compass deviation is the difference between the compass indications when installed in the aircraft compared to the indications when the compass is outside the aircraft (free from disturbing magnetic forces of the aircraft). The compass needle is affected ~hen aircraft electrical equipment is operated and by the ferrous metallic components within the aircraft. These interne! magnetic fields tend to deflect the compass needle from its alignment with the Magnetic north Deviation varies, depending upon which electrical components are in use. The aircraft magnetic fields may also change as a result of mechanical jolts to the aircraft, from the installation of additional or different radio, equipment, or major mechanical work on an engine such as changing of the crankshaft or propeller. The crankshaft and the propeller are particularly susceptible to changes in inherent magnetism because they rotate in various magnetic fields. As mentioned above, the compass deviation is caused by two factors - by hard iron magnetism in combination with soft iron magnetism. Hard iron magnetism is known as the permanent magnetism and soft iron magnetism is known as temporary magnetism. With reference to compass deviation, the hard iron magnetic deviation is caused by the airframe structure itself - it is not further influenced by the Earth's magnetic field. It is compensated by the pilot by using the deviation card. The Soft iron magnetic deviation is caused by the Earth's magnetic field, which induces magnetism in soft iron pieces (airframe components, electrical equipment, etc.). It is corrected for by using a compass correction devices consisting of permanent magnets (mechanical correction) or using electrical correction devices on more complex compass systems (typically remote compass systems). 198- The compass heading can be derived from the magnetic heading by reference to a:

A) map showing the isogonic lines. B) map showing the isoclinic lines. C) deviation correction curve. D) compass swinging curve.

(Refer to figure 022-E14)

Due to the influence of ferromagnetic material or electrical circuits on board the aircraft, the compass will not indicate the correct magnetic heading, but the compass heading instead. Compass deviation is the difference between the compass indications when installed in the aircraft compared to the indications when the compass is outside the aircraft (free from disturbing magnetic forces of the aircraft). The compass needle is affected when aircraft electrical equipment is operated and by the ferrous metallic components within the aircraft. These internal magnetic fields tend to deflect the compass needle from its alignment with the Magnetic North. Compass deviation is expressed as - at how many degrees East(+) or West(-) is the Compass North situated from the Magnetic North (see the attached figure). The compass swing is a procedure by which the deviation is measured for various headings. The compass heading can be derived from the magnetic heading by reference to a compass swinging curve => in a tabulated form known as the Compass Deviation Card. 199- Magnetic compass swinging is carried out to reduce as much as possible:

A) variation. B) deviation . C) regulation. D) acceleration.

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200- . The fields affecting a magnetic compass originate from: 1)magnetic masses 2)ferrous metal masses 3)non ferrous metal masses 4)electrical currents

The combination of correct statements is: A)1,2,3 B)1,2,4 C)1,2,3,4 D)1,3,4

201- The magnetic heading can be derived from the compass heading by reference to a:

A) magnetic variation correction card. B) map showing the magnetic variation lines. C) compass deviation card. D) map showing the isogonic lines.

202- Concerning magnetic compasses, deviation is: A) the angular difference between Magnetic North and True North .. B) the angular difference between Magnetic North and Compass North.

C)Compass North. \ D)a card in the cockpit showing compass heading errors.

203- During deceleration following a landing in a southerly direction, a magnetic compass made for the northern hemisphere indicates:

A) an apparent turn to the west. B) no apparent turn only on northern latitudes. C) no apparent turn. D)an apparent turn to the east.

(Refer to figures 022-E17 and 022-E18) On a Direct Reading Compass a magnet assembly is suspended in liquid which aligns itself with the horizontal component of the Earth's magnetic field, i.e. It seeks the magnetic meridian. It is subjected to turning and acceleration errors: Acceleration errors: (ANDS => accelerate north, decelerate south) • If the aircraft accelerates on westerly or easterly heading, the compass will indicate an apparent turn towards

north; • If the aircraft decelerates on westerly or easterly heading, the compass will indicate an apparent turn towards

south; • On a northerly or southerly heading the acceleration error is zero because the inertial force is in a north-

south direction, i.e. along the ,magnet and thus. it will displace it neither clockwise, nor anticlockwise. Turning errors: (UNOS => undershoot north, overshoot south) • When the aircraft is turning through a northerly heading. the pilot must undershoot the target heading; • When the aircraft is turning through a southerly heading, the pilot must overshoot the target heading; • When turning through an easterly or westerly heading, the turning error is zero.

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Note: all of the info above is based on a Northern hemisphere. It is reversed in~;the Southern hemisphere. 204- A pilot wishes to turn left on to a southerly heading with 20" bank at a latitude of 20" North. Using a direct reading compass, in order to achieve this he must stop the turn on an approximate heading of:

A) 190" B)200" C) 170" D) 160"

(Refer to figures 022-E17 and 022-E18) The aircraft is turning left on a southerly heading (180"), i.e. the aircraft is turning anti-clockwise. According to the mnemonic "UNOS” we know to Undershoot North, Overshoot South. OK, if we overshoot the south turning in a anti-clockwise position then the answer is going to be less than 180". That leaves us with two possible answers. The key lies in the information specifying the bank angle and the latitude. A quick rule of thumb says that we should overshoot or undershoot by roughly the amount resulting from this formula: (bank angle + latitude)/ 2. In our case the bank angle is 20" and the lat is 20". Using the formula (20+20)/2 we get a value of 20". Therefore, we will overshoot, by 20", which means on a heading of 160" (180-20). This overshoot undershoot correction should not exceed a value of 30". Even if you get a higher value as a result of using the

formula, use 3D" as a maximum. . Note: try to visualize the manoeuver and do not get confused by the anti-clockwise turn. That means that you will be "arriving" onto the southern heading from the westerly heading - with a left turn - in this situation overshooting means heading less than 180°. 205-In the northern hemisphere, during deceleration following a landing in an easterly direction, the magnetic compass will indicate:

A) an apparent turn to the south. B) an apparent turn to the north. C) a constant heading. D) a heading fluctuating about 090°.

206- In the northern hemisphere, during deceleration following a landing in a westerly direction, the magnetic compass will indicate:

A) a heading fluctuating about 270Q• B)an apparent turn to the north. C)C) no apparent turn. D)an apparent turn to the south.

207- A pilot wishes to turn right on to a northerly heading with 20Q bank at a latitude of 400 North. Using a direct reading compass, in order to achieve this he must stop the turn on to an approximate heading of:

A) 030° B) 350° C) 330° D) 0100

(Refer to figures 022-E17 and 022-E18) The aircraft is turning right onto a northerly heading (POO·), i.e. the aircraft is turning clockwise (from a Westerly direction). According to the mnemonic "UNOS" we know to Undershoot North, Overshoot South. OK, if we undershoot the north turning in a clockwise position then the answer is going to be less

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than 000'. That leaves us with two possible answers. The key lies in the information specifying the bank angle and the latitude. A quick rule of thumb says that we should overshoot or undershoot by roughly the amount resulting from this formula: (bank angle + latitude) + 2. In our case the bank angle is 20· and the lat is 40°. Using the formula (20+40)+2 we get a value of 3D'. Therefore, we will undershoot by 3D', which means on a heading of 330· (360-30). This overshoot/undershoot correction should not exceed a value of 3D'. Even if you get a higher value as a result of using the formula, use 30' as a maximum. Note: try to visualize the manoeuver and do not get confused by the clockwise turn. That means that you will be "arriving" onto the northern heading from the westerly heading - turning right - in this situation undershooting means heading less than 360'. 208- If an aircraft, fitted with a Direct Reading Magnetic Compass (DRMC), takes off on a westerly heading, in the northern hemisphere, the DRMC will indicate:

A)a turn to the north. B)oscillates about west. C)C) no turn. D)a turn to south.

209- When turning onto a northerly heading the rose of a magnetic compass tends to "undershoot"; when turning onto

a southerly heading it tends to "overshoot: 1)These compass indications are less reliable in the northern hemisphere than in

the southern hemisphere. 2)These compass oscillations following a lateral gust are not identical if the aircraft is heading north or south. 3) This behaviour is due to the mechanical construction of the compass. 4)This behaviour is a symptom of a badly swung compass. The correct statements are:

A) 2,3,4 B) 1,2,4 C) 2, 3 D) 1,3

210- During deceleration following a landing in a northerly direction, a magnetic compass made for the southern hemisphere Indicates:

A)no apparent turn. B) an apparent turn to the east. C) an apparent turn to the west. D)a heading fluctuating about 3600.

211- An-aircraft is taking off on a runway heading 0450, in still air, with a compass having 00 deviation. The runway is on an agonic line. What will the compass read if you are in the northern hemisphere? .

A) Compass moves to less than 045°. B) Compass moves to more than 045°. C) Compass stays on 045° if wings are kept level. D) Compass remains on 045°.

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212- In the southern hemisphere, during deceleration following a landing in an easterly direction, the magnetic compass will indicate: -

A) a heading fluctuating about 0900• B) an apparent turn to the south. C) no apparent turn. D) an apparent turn to the north.

213- A pilot wishes to turn left on to a northerly heading with 10" bank at a latitude of 50" North. Using a direct reading compass, in order to achieve this he must stop the turn on an approximate heading of:

A) 355° B)030° C)3300 D)0150

(Refer to figures 022-E17 and 022-E18) The aircraft is turning left onto a northerly heading (0000), i.e. the aircraft is turning anti-clockwise. According to the mnemonic “UNOS" we know to Undershoot North, Overshoot South. OK, if we undershoot the north turning in an anti-clockwise position then the answer is going to be more than 0000.That leaves us with two possible answers. The key lies in the information specifying the bank angle and the latitude. A quick rule of thumb says that we should overshoot or undershoot by roughly the amount resulting from this formula: (bank angle + latitude) + 2. In our case the bank angle is 100 and the lat is 500• Using the formula (10+50)+2 we get a value of 300• Therefore, we will undershoot by 300, which means on a heading of 0300 (000+30). This overshoot/undershoot correction should not exceed a value of 300• Even if you get a higher value as a result of using the formula, use 300 as a maximum. Note: try to visualize the manoeuver and do not get confused by the anti-clockwise turn. That means that you will be "arriving" onto the northern heading from the easterly heading - with a left turn - in this situation undershooting means heading more than 0000•

214- An aircraft is fitted with a direct reading magnetic compass. Upon landing in a northerly direction the compass will indicate:

A) no change. B) an oscillation to its north alignment. C) a turn towards east. D) a turn towards west.

215- A pilot wishes to turn right on to a southerly heading with 200 bank at a latitude of 20" North. Using a direct reading compass, in order to achieve this he must stop the turn on an approximate heading of:

A) 170° B)

C) 2000 1500

D) 190°

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(Refer to figures 022-£17 and 022-£18) The aircraft is turning right onto a southerly heading (180°), i.e. the aircraft is turning clockwise. According to the mnemonic “UNOS" we know to Undershoot North, Overshoot South. OK, if we overshoot the south turning in a clockwise position then the answer is going to be more than 180·. That leaves us with 2 possible answers. The key lies in the information specifying the bank angle and the latitude. A quick rule of thumb says that we should overshoot or undershoot by roughly the amount resulting from this formula: (bank angle + latitude)/ 2. In our case the bank angle is 200 and the lat is 200• Using the formula (20+20)/2 we get a value of 200• Therefore, we will overshoot by 200, which means on a heading of 2000 (180+20). This overshoot/undershoot correction should not exceed a value of 300• Even if you get a higher value as a result of using the formula, use 30· as a maximum. Note: try to visualize the manoeuver and do not get confused by the clockwise turn. That means that you will be "arriving" onto the southerly heading from the easterly heading - with a right turn - in this situation under Shooting means heading more than 1800•

216- Which of the following will effect a direct reading compass? 1)ferrous metals 2)nonferrous metals 3)electrical equipment

A) 1 B) 1,3 C)1,2 D)1,2,3

217- In the southern hemisphere, during deceleration following a landing in a westerly direction, the magnetic Compass will indicate:

A) no apparent turn. B) a heading fluctuation about 270". C) an apparent turn to the north. D) an apparent turn to the south.

218- In northern hemisphere, an aircraft takes off on a runway with an alignment ot 45". The isogonic line on the area chart indicates 0". The compass deviation is 0°. On a takeoff with zero wind, the compass error:

A) will be null. B) is such that the compass will indicate a value noticeably below 045°. C) is such that the compass will indicate a value noticeably above 045°. D) will be null if the wings are kept level.

(Refer to figures 022-E17 and 022-E18) Acceleration errors: (ANDS =:> accelerate north, decelerate south) • If the aircraft accelerates on westerly or easterly heading, the compass will indicate an apparent turn

towards north (in the Northern hemisphere) • If the aircraft decelerates on westerly or easterly heading, the compass will indicate an apparent turn

towards south (iii the Northern hemisphere) - • On a northerly or southerly heading the acceleration error is zero because the inertial force is in a north-

south direction, i.e. along the magnet and thus, it will displace it neither clockwise, nor anti-

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clockwise. We know that .the 'acceleration errors are prominent on easterly or westerly headings and gradually reduce to zero error towards the north or south headings. With a runway aligned with 045° we will still experience a slight acceleration error, although not at the same magnitude as would should the runway be aligned with 090°. From the mnemonic ANDS we know that acceleration will result in an apparent turn towards the north - in our case that would mean a smaller heading. With a runway heading of 045" the compass will indicate a value below 045" during Our acceleration.

219- About a magnetic compass:

A) errors of parallax are due to the oscillation of the com- pass rose.

B)acceleration errors are due to the compass deviation. C)acceleration errors are due to Schuler oscillations. D)turning error is due to the vertical component of the earth's magnetic field.

220- Concerning the direct reading magnetic compass, the turning error: A) does not depend on the magnetic latitude. B) decreases with the magnetic latitude. C) increases with the magnetic latitude. D) decreases with the magnetic longitude.

221- Magnetic compass errors are: A) parallax errors due to compass rose oscillations. B) due to the lateral gusts which occur when the aircraft is heading eastward or westward. C) due to Schuler oscillations. D) due to north change, depending on the bank angle and magnetic heading.

222- The direct indicating compass is no more reliable when approaching: 1)the magnetic poles 2)the magnetic equator with an east or west heading 3)the magnetic equator with a north or south heading

The combination regrouping all the correct statements is: A) 1,2 B)1,2,3 C)1 D) 1,3

223- The turning errors of a direct reading magnetic compass are:

A) maximum at the magnetic equator. B) maximum at the magnetic poles. C) minimum at a latitude of 45°. D) minimum at the magnetic poles.

224- The main cause of error in a DRMC is: A) parallax in the rose

B) turning. C) magnetic deviation.

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D) latitude.

225- A factor giving an error on a direct indicating compass would be:

A) crosswinds - particularly on east/west headings. B)parallax due to oscillations of the compass rose. C) acceleration on east/west headings. D)turning through east/west headings.

226- An aircraft turns to the right, through 90° heading, onto a heading of North, at 48°N, using a direct indicating compass .The aircraft bank angle is 30°. What heading should the aircraft roll out on?

A) 0100 B)0300 C)330° D)350°

(Refer to figures 022-E17 and 022-E18) The aircraft is turning right onto a northerly heading (0000), i.e. the aircraft is turning clockwise. According to the mnemonic "UNOS" we know to Undershoot North, Overshoot South. OK, if we undershoot the north turning in a clockwise position then the answer is going to be less than 000°. That leaves us with two possible answers. The key lies in the information specifying the bank angle and the latitude. A quick rule of thumb says that we should overshoot or undershoot by roughly the amount resulting from this formula: (bank angle + latitude)/ 2. In our case the bank angle is 30° and the lat is 48". Using the formula (30 + 48)/ 2 we get a value of 39". Therefore, we should theoretically undershoot by 39°, which means on a heading of 320° (360 - 30). However, this overshoot / undershoot correction should not exceed a value of 30",Even if we get a higher value as a result of using the formula, we use 30" as a maximum - therefore, the correct answer will be 330° (360· 30). Note: try to visualize the manoeuver and do not get confused by the clockwise turn. If you start on a heading of 090° and are making a right turn towards the north, that means that you will be "arriving" onto the northerly heading from the westerly heading - in this situation undershooting means heading less than 360". 227- You commence a rate 2 turn from south-east to southwest, in the northern

hemisphere. On what heading do you stop the turn? A) 215d B) 2550 C) 225° D) 2050

(Refer to figures 022-E17 and 022-E18) The aircraft is turning right onto a south-westerly heading (2250), i.e. the aircraft is turning clockwise. According to the mnemonic "UNOS" we know to Undershoot North, Overshoot South. OK, if we overshoot the SW heading in a clockwise position then the answer is going to be more than 225". That leaves us with only one possible answer => 255°.

Note: try to visualize the manoeuver and do not get confused by the clockwise turn. That means that you will be "arriving" onto the SW heading of 225° from the southerly heading - with a right turn - in this situation overshooting means heading more than 225°.

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228- An aircraft lands on a southerly direction in the northern hemisphere. The compass indication will:

A) oscillate about 180°. B) not change. C) increase. D) decrease.

229- About a magnetic compass: A) turning error is due to the angle of dip.

B) acceleration errors are due to crosswind and gusts. C) acceleration errors are due to Schuler oscillations.

D)errors of parallax are due to the oscillation of the compass rose.

230- In the northern hemisphere, a magnetic compass will normally indicate a turn towards north if:

A) an aircraft is accelerated while on an east or west heading. B) an aircraft is decelerated while on an east or west heading. C)a left turn is entered from a west heading . D) a right turn is entered from an east heading.

231- The main reason for having the centre of gravity below the pivot point in a card-type magnetic compass is:

A) to compensate for the horizontal magnetic component H such that the magnet system is within approx. 2" of the true horizontal between 60° and 40° S.

B)to cancel out the systems pendulosity and its tendency to oscillate backwards and forwards about its equilibrium position. C)to make it less sensitive to hard- and soft-iron magnetism in the aircraft. D)to compensate for the vertical magnetic component Z such that the magnet system is within approx. 20 of the true horizontal between 60" and 40° S.

If a magnet were pivoted at its centre on a pin, it would dip to lie in the plane of the Earth's total field. Even in mid latitudes, the dip angle would be unacceptably high. To overcome this problem, a system of pendulous suspension is employed. The success of the system lies in the fact that the centre of gravity of the magnets lies below the pivot point. Thus the dipping effect due to the vertical (Z) component of the Earth's magnetic field is opposed by the weight of the magnets.

232- In the northern hemisphere, a magnetic compass will normally indicate a turn towards north if:

A) a right turn is entered from an east heading. S) a left turn is entered from a west heading. C) an aircraft is decelerated while on an east or west heading. D) an aircraft is accelerated while on an east or west heading.

233- What should be the indication on the magnetic compass when rolling into a standard rate turn to the right from a south heading in the northern hemisphere?

A) The compass will indicate a turn to the right, but at a faster rate than is actually occurring.

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B) The compass will indicate a turn to the left. C)The compass will remain on south for a short time, then gradually catch up to the magnetic heading of the airplane. D)The compass will indicate the approximate correct magnetic heading if the roll into the turn is smooth.

234-In the building principle of a gyroscope, the best efficiency is obtained through the concentration of the mass:

A) on the periphery and with a high rotation speed. B) close to the axis and with a high rotation speed.

C)on the periphery and with a low rotation speed. D)close to the axis and with a low rotation speed.

(Refer to figures 022-E25 and 022-E26) Rigidity in space refers to the principle that a gyroscope remains in a fixed position in the plane in which it is spinning. By mounting this wheel, or gyroscope, on a set of gimbal rings, the gyro is able .to rotate freely in any direction. Thus, if the gimbal rings are tilted, twisted, or otherwise moved, the gyro remains in the plane in which it was originally spinning. Rigidity in space is the property, which is a direct product of the angular momentum. Increased angular momentum will increase the rigidity in space. When a mass is in motion it has an ability to continue this motion unless acted upon by some external force. The ability to maintain motion is known as "momentum". Momentum is really a measure of the quantity of motion of the moving mass and is given by the product of the mass (M) and the velocity (V). A wheel in rotation also has mass and that mass is in motion around the axis. Imagine the wheel to consist of a number of segments, each one very small. Each segment has a mass that can be considered to be at its centre gravity as indicated. The velocity of that mass will be governed by the radius of the centre of gravity from the centre of rotation. We will refer to this centre of rotation as the spin axis. Each segment will now have a momentum of mass (M) x radius (R)x angular rate of rotation (w). However, its momentum is constrained to follow a circular path and it is referred to as angular momentum. If we sum up the momentum of each little element of the wheel we will get the total angular momentum. This can be calculated by obtaining the product of M x R x w. Where: - M= is the total mass of the wheel R = is the radius from the centre of spin to the circle marking the line of the effective CG of each element W= is the angular rate of rotation

From this we can see that increasing the rate of rotation, the mass or the effective radius of that mass can increase the angular momentum. Now if we place our wheel in an assembly of bearings, it will be able to rotate around its spin axis, which is held in the inner frame.

235 The rigidity of a gyro is improved by:

A) increasing RPM and concentrating the mass on the periphery of the rotor. B) increasing RPM and concentrating the mass at the hub of the rotor.

C)decreasing RPM and concentrating the mass on the periphery of the rotor. D)decreasing RPM and concentrating the mass at the hub of the rotor.

236-A 2 axis gyro measuring vertical changes will have: A) one degree of freedom vertical axis.

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B) two degrees of freedom vertical axis. C) One degree of freedom horizontal axis. D) Two degrees of freedom horizontal axis.

(Refer to figures 022-E25, 022-E26, 022-E27, 022-E28, 022-E29, 022-E30 and 022-E31)

Gyros are typically classified by the degree of freedom permitted of each type and by the plane in which the axis of the gyro is located. .Turn indicator has a freedom in only 1 axis. The rotor spin axis is horizontal (parallel to the aircraft's lateral axis = pitch axis).

•The Artificial Horizon has a freedom in 2 axis. The rotor spin axis , is vertical (parallel to the aircraft's vertical axis= yaw axis).

• The DGI (Directional Gyro Indicator) has a freedom in 2 axis. The rotor spin axis is horizontal.

NOTE: the degree(s) of freedom of a gyro does not take into account its rotor spin axis according to the JAA Learning Objectives

237- What is the maximum drift of a gyro, due to Earth rate? A) 90° per hour. B) 180° per hour. C) 15° per hour. D) 5° per hour.

238- The term drift refers to the wander of the axis of gyro in:

A) the vertical and horizontal plane. B) the vertical plane. C) the horizontal plane. D) any plane.

239- The basic properties of a gyroscope are: 1)The gyros weight. 2)The rigidity in space. 3)The inertia. 4)The high RPM. 5)The precession. The combination of correct statements is:

A) 3,4 B)2,5 C) 2, 3, 5 D) 1,3,5

(Refer to figures 022-E25 and 022-E26) There are two fundamental properties of gyroscopic action - rigidity in space and precession. Rigidity in space refers to the principle that a gyroscope remains in a fixed position in the plane in which it is spinning. By mounting this wheel, or gyroscope, on a set of gimbal rings, the gyro is able to rotate freely in any direction. Thus, if the gimbal rings are tilted, twisted, or otherwise moved, the gyro

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remains in the plane in which it was originally spinning. Rigidity in space is the property, which is a direct product of the angular momentum. Increased angular momentum will Increase the rigidity in space. As an example we can take a look at a bicycle => a bicycle is easier to balance at high speed than when it is barely moving. At high speed, the bicycle wheels act as gyros, and tend to keep their axes (axles) parallel to the ground. Precession is the tilting or turning of a gyro in response to a deflective force. The reaction to this force does not occur at the point where it was applied; rather, it occurs at a point that is 90° later in the direction of rotation. This principle allows the gyro to determine a rate of turn by sensing the amount of pressure created by a change in direction. The rate at which the gyro precesses is inversely proportional to the speed of the rotor and proportional to the deflective force. Precession can also create some minor errors in some instruments. 240-(Refer to figure 022-19) The diagram shows three gyro assemblies: A, Band C. Among these gyros: 1)is a roll gyro 2)is a pitch gyro 3)is a yaw gyro The correct matching of gyros and assemblies is:

A) 1C, 2B, 3A B) 1B, 2A, 3C

C) 1A, 2B, 3C D) 1B, 2C, 3A

(Refer to figures 022-E25, 022-E26, 022-E27, 022-E28, 022-E29, 022-E30 and 022-E31) Gyros are typically classified by the degree of freedom permitted of each type and by the plane in which the axis of the gyro is located: • The turn indicator has a horizontal rotor spin axis ar{d freedom in

only 1 axis. : • The artificial horizon has a vertical rotor spin axis and freedom in 2 axis • The DGI (Directional Gyro Indicator) has a horizontal spin axis and freedom in 2 axis.

The picture attachment provided by the JAA is a terrible illustration. Unfortunately a detailed explanation is not available at this time

241- The inertia of a gyroscope is greater when: A) its rotation speed is lower and the mass of the spinning wheel is located further from the axis of

rotation. B) its rotation speed is higher and the mass of the spinning wheel is closer to the axis of rotation. C) its rotation speed is higher and the mass of the spinning wheel is located further from the axis of

rotation. D)its rotation speed is lower and the mass of the spinning wheel is closer to the axis of rotation. For explanation refer to question #2701 on page 63

242- The properties of a gyroscope are: 1)rigidity in space 2)rigidity on Earth 3)precession 4)Schuler oscillations The combination regrouping all the correct statements is:

A) 1,4

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B)2,3 C)1,3 D)2,4

243- Without any external action, the axis of a free gyroscope is fixed with reference to:

A) the apparent vertical. B) the earth. C)the aircraft. D) space.

244- The properties of a gyro are: 1)mass 2)rigidity 3)Inertia 4)precession 5)rotational speed

A) 1,2,3,5 B) 2,4 C)2,3,5 D)1,3

245- How can you increase the rigidity of a gyroscope?

A) Concentrate the mass near the spin axis at a high RPM. .. B) Concentrate the mass at the periphery at a high RPM. C) Concentrate the mass near the spin axis at a low RPM .. D)Concentrate the mass at the periphery at a low RPM.

246- Rigidity in a gyroscope is:

A) a way to express the stability of the inner and out gimbal rings. B) to what extremes the flight attitudes might be before the gyro topples.

C) the reaction 90° in the direction of rotation when apply ing force to the spinning wheel. D)the tendency it has to remain in its plane of rotation and resist attempts to alter its position.

247- Precession in a gyroscope is: A) the tendency it has to remain in its plane of rotation. B) a caging device. C) the angular limits to which the gimbals may travel before the gyro topples and the

indication becomes useless. D)the reaction at 90° in direction of rotation caused by a applied force to the spinning wheel.

248- How is vacuum provided for the air driven gyro instruments? A) By the static tube.

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B) By an engine-driven pump. C) By the static vent. D)All of the above.

(Refer to figures 022-E27 and 022-E28) In order to assume the properties of a gyroscope the gyro wheel (or rotor) must be rotated. It follows that this will require the application of some power. In addition, when considering a 'tied' gyro, we must also apply a controlling force and this requires a power source. Conventional gyroscopes in aircraft are either air driven or electrically driven.

Air Driven Gyros - are Widely used on small aircraft and are still found on some large aircraft in the role of stand-by or emergency instruments. In the air driven gyro, the gyro is contained in an airtight case. The case is attached to a vacuum source by a pipeline. This source is normally an engine driven vacuum pump but, in very simple aeroplanes, may be a venturi tube attached to the outside of the fuselage. The gyro wheel has buckets cut in the outer rim. It is encased in a shroud, which acts as the inner gimbal and has a pipeline attached. This pipeline terminates at a small opening that is designed to direct the airflow onto the buckets. The shroud has an exhaust port to allow air to escape to the outer case. The pipeline from the inner gimbal is fed through the inner gimbal axis along the outer gimbal and through its axis then to a filter system that covers a hole in the outer case. Now when the vacuum is applied the pressure in the outer case will drop. Replacement air entering the system from outside the case will pass through the filter, through the piping system and will impact on the buckets on the rotor. The air then escapes from the rotor shroud and this escape path can be designed to provide a controlling force to "tie" the gyro. Excessive values of "suction" and therefore excessive rotational speed of the gyros Is prevented using the Vacuum Relief Valve. During system operation the relief valve remains closed by compression of a spring, the tension of which Is pre-adjusted to obtain the required vacuum so that air pressure acting on the outside of the valve is balanced against spring tension. If for some reason the adjusted value should be exceeded, the outside air pressure would overcome spring tension thus opening the valve to allow outside air to flow Into the system until the balanced condition is again restored.

249-Air driven gyro rotors are prevented from spinning too fast by the:

A) air filter. B) vacuum relief valve. C) suction gauge. D)bearing friction.

250- What is the main cause of precession?

A) Magnetic variation. B) Magnetic declination. C) Bearing friction. D)The Earth's rotation.

(Refer to figures 022-E25 and 022-E26) Precession is the tilting or turning of a gyro in response to a deflective force. The reaction to this force does not occur at the point where it was applied; rather, it occurs at a point that is 900 later in the direction of rotation. This principle allows the gyro to determine a rate of tum by sensing the amount of pressure created by a change in direction. The rate at which the gyro precesses is inversely proportional to the speed of the rotor and proportional to the deflective force. Precession can also create some minor errors in some instru-ments. It should be noted here that gyros, no matter how carefully manufactured, are not mechanically perfect. Friction in the bearings of the axes will affect the momentum of the system. Friction on the spin axis will cause the gyro to slow down. Friction on either or both of the other two axes will cause torque forces around those axes. If friction causes torque around the vertical axis, that torque will be processed through 90 ° and

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will act around a horizontal axis causing the gyro to tilt. Similarly, if friction torque is present around a horizontal axis, it will be precessed to act around the vertical axis and the gyro will drift. These effects have got nothing to do with the rotation of the earth. They are of purely mechanical origin and are known as real wander.

251- A turn indicator is an instrument which indicates rate of turn. Rate of turn depends upon: 1)bank angle 2)aeroplane speed 3)aeroplane weight The combination regrouping the correct statements is:

A)2,3 B)1,2,3 C) 1,2 D) 1,3

(Refer to figures 022-E30 and 022-E31) The rate of turn indicated on a Turn Indicator is a function of gyro tilt. Scale is calibrated in what are termed standard rates and, although seldom marked on the instrument, are classified by the numbers 1 to 4, corresponding to turn rates of 180" (Rate 1), 3600 (Rate 2), 540· (Rate 3) and 720· (Rate 4) per minute. On commercial aeroplanes the scale is normally only graduated to indicate rate 1 turns.

The rate-of-turn indicator measures the rate about the yaw axis, but at low bank angles it is nearly the same as angular velocity about the vertical axis. Rate of turn is directly proportional to bank angle and inversely proportional to TAS (True Air Speed). It is completely independent of weight of the aircraft. Higher bank angle will result in a greater rate of turn (faster heading change), whereas a higher airspeed will result in a smaller rate of turn (slower heading change). Therefore the largest rate of turn is achieved with high angle of bank and low TAS. The formula for calculating the required bank angle to produce a "Rate 1" turn is: Angle of bank = (TAS/ 10) + 7

252- An aircraft is flying at a 120 kts TAS. In order to achieve a Rate 1 turn, the pilot will have to bank the aircraft at an angle of:

A)30" B) 120

C) 360 D) 180

An approximate calculation of the required angle of bank for Rate 1 turns is: Angle of bank = (TAS/10) + 7. In our case it is (120/10) + 7 = 190. To achieve a Rate 1 turn (1800 per minute), with TAS of 120 KTS the bank angle must be 190 (180 being the closest answer here). 253- On the ground, during a right turn, the turn indicator indicates:

A) needle to the right, ball to left. B) needle to the right, ball to right. C)needle in the middle, ball to right. D) needle in the middle, ball to left.

(Refer to figures 022-E30 and 022-E31) For the turn to be balanced (= no Slip & no Skid), the angle of bank must be appropriate for the TAS

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and the rate of turn used:

• Bank angle is excessive => aircraft is SLIPPING in and the ball is displaced to the inside of the turn (for example, if the aircraft is turning right, the ball will be to the right).

• Bank angle is insufficient => aircraft is SKIDDING out and the ball is displaced to the outside of the tum (for example, if the aircraft is turning right, the ball will be to the left).

Pre-flight (taxi) checks of Turn Indicator: for an electrical instrument, check that the ·OFF" flag has disappeared. During taxi, check that the needle indicates a turn in the direction of the turn and that the ball indicates a skid = ball will be displaced to the outside of the turn. For example, during a right turn while taxiing, the bank angle is zero (thus, lower than required) and therefore the ball will be to the left The needle from the rate of turn indicator shows the rate of turn in flight, as well as on the ground. => the needle will be to the right. In a left turn, the needle will show left, ball will be displaced to the right 254- If the needle and the ball of a Turn and Slip indicator both show right, what does it indicate:

A) turn to left and too much bank. B) turn to right and too much bank. C)turn to left and too little bank. D) turn to right and too little bank

(Refer to figures 022-E30, 022-E31 and 022-E06) For the turn to be balanced (= no Slip & no Skid), the angle of bank must be appropriate for the TAS and the rate of turn used:

• Bank angle is excessive => aircraft is SLIPPING in and the ball is displaced to the inside of the turn

(for example, if the aircraft is turning right, the ball will be to the right). Two possibilities for correcting this 'situation: either reduce the bank angle or apply more rudder in the direction of the turn. • Bank angle is Insufficient => aircraft is SKIDDING out and the ball is displaced to the outside of the

turn (for example, if the aircraft is turning right, the ball will be to the left). Two possibilities for correcting this situation: either increase the bank angle or apply less rudder in the direction of the turn.

A summary: • Balanced turn => needle will be deflected in the direction of tn« tum; ball will be centered.

• Slipping turn => both the needle and ball will be deflected in the

direction of the turn. I • Skidding turn => needle will be deflected in the direction of the turn; ball will be deflected in the

opposite side.

255-In a right turn while taxiing, the correct indications on Turn and Slip Indicator are:

A) needle left, ball right. B) needle left, ball left. C) needle right, ball right. D)needle right, ball left.

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256- On the ground, during a left turn, the turn indicator indicates: A)needle in the middle, ball to the left. B) needle to the left, ball to the left. C) needle in the middle, ball to the right. D) needle to the left, ball to the right.

257-When. in flight, the needle and ball of a needle-and-ball indicator are on the left, the aircraft is:

A) turning left with not enough bank. B) turning left with too much bank . C)turning right with too much bank. D) turning right with not enough bank.

258- The rate of turn is the: A) yaw rate in a turn. B) change-of-heading rate of the aircraft. C)aircraft speed in a turn. D)pitch rate in a turn.

(Refer to figures 022-E30 and 022-E31) Two types of turn and balance indicators are considered: the traditional Turn and Slip (or turn and balance) indicator, and the turn coordinator.

• Turn and Slip indicator is in fact two instruments in one. The turn indicator shows the "Rate of

Turn" of the aircraft, and utilizes the properties of a rate gyro. The slip indicator enables the pilot to fly the aircraft in balance, keeping the ball in the middle, and employs a simple pendulum device - it provides the "Turn Coordination" information. The rate of turn indicated on a Turn Indicator is a function of gyro tilt. Scale is calibrated in what are termed standard rates and, although seldom marked on the instrument, are classified by the numbers 1 to 4, corresponding to turn rates of 1800 (Rate 1), 3600 (Rate 2),5400 (Rate 3) and 7200 (Rate 4) per minute. On commercial aeroplanes the scale is normally only graduated to indicate rate 1 turns. The rate-of-turn indicator measures the rate of turn about the aircraft's yaw axis, but at low bank angles it is nearly the same as angular velocity about the vertical axis.

• Turn Coordinator is a development of the Turn and Balance indicator and is used in place of such instruments in a large number of small, general aviation aircraft. The primary difference is in the lo-cation of the precession axis of the rate gyroscope. The gyroscope is spring-restrained and is mounted so that the axis is at about 300 with respect to the aircraft's fore-and-aft axis, thus making the gyroscope sensitive to banking as well as turning of the aircraft. The, turn coordinator integrates both the rate of roll and the rate of turn, so as 'to give a presentation of what the aircraft is actually doing, not what it has done. It indicates the Rate of Turn and "Roll Rate" on its display. The aeroplane symbol of the turn coordinator moves in the 'direction of turn or roll, unlike the artificial horizon where the symbol is fixed to the instrument case and the horizon bar 'moves. The annotation "no pitch information" is sometime given on the indicator« scale so as to avoid confusion in pitch control that might result: from the instrument's similarity to a gyro horizon.

259- On a turn and slip indicator, needle to the left and ball to the right indicates:

A) turn to the right, not enough bank.

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B) turn to the left, too much bank. C)turn to the left, not enough bank. D)turn to the right, too much bank.

260- In a turn at a constant angle of bank, the turn indicator reading is:

A) independent to the aircraft true airspeed. B) proportional to the aircraft true airspeed. C)inversely proportional to the aircraft true airspeed. D) proportional to the aircraft weight.

261- In a left turn while taxiing, the correct indications are:

A) needle left, ball right. B) needle left, ball left. C) needle right, ball right. D) needle right, ball left.

262- When, in flight, the needle and ball of a needle-and-ball indicator are on the right, the aircraft is:

A) turning left with too much bank. B) turning right with not enough bank. C)turning right with too much bank. D)turning left with not enough bank.

263- In a left turn, the ball of the turn coordinator is out to the right, what corrective action is required?

A) Less right rudder. B) Less left bank. C) More left bank. D) More left rudder.

264- In a turn at constant angle of bank, the rate of turn is: A) independent of weight and proportional a to TAS. B) dependant on weight and inversely proportional to TAS. C) independent of weight and inversely proportional a to TAS. D) dependant on weight and proportional to TAS.

265- When, in flight, the needle of a needle-and-bal/ indicator is on the right and the ball on the left, the aircraft is:

A) turning left with not enough bank. B) turning left with too much bank. C) turning right with not enough bank. D) turning right with too much bank.

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266- At a low bank angle, the measurement of rate-of-turn actually consists in measuring the:

A) pitch rate of the aircraft. B) roll rate of the aircraft. C) angular velocity of the aircraft. D) yaw rate of the aircraft.

267- When, in flight, the needle of a needle-and-ball indicator is on the left and the ball on the right, the aircraft is:

A) turning right with not enough bank. B) turning right with too much bank. C) turning left with not enough bank. D) turning left with too much bank.

268- In a turn indicator, the measurement for rate of turn consists of: A) low bank angle, in measuring the roll rate. B) low bank angle, in measuring the yaw rate. C) high bank angle, in measuring the yaw rate. D) high bank angle, in measuring the roll rate.

269- Under normal operating conditions, when an aircraft is in a banked turn, the rate-or-turn indicator is a valuable gyroscopic flight control instrument. When it is used together with an attitude indicator, the rate-of-turn indicator provides information on: 1)the angular velocity of the aircraft about the yaw axis 2) the bank of the aircraft 3)the direction of the aircraft turn 4)the angular velocity of the aircraft about the real vertical

The combination of correct statements is: A)3,4 B) 2,4 C) 1,3 D)1,2

270-(Refer to figure 022-14) The diagram representing a left turn with insufficient rudder is: A) 2 B)3 C)4 D)1

(Refer to figures 022·E30, 022-E31 and 022-E06) For the turn to be balanced (= no Slip & no Skid), the angle of bank must be appropriate for the TAS and the rate of turn used:

• Bank angle is excessive => aircraft is SLIPPING in and the ball is displaced to the inside of the turn

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(for example, if the aircraft is' turning right, the bell will be to the right). Two possibilities for cor-recting this situation: either reduce the bank angle or apply more rudder in the direction of the turn. . • Bank angle is insufficient => aircraft is SKIDING out and the ball is displaced to the outside of the

turn (for example, if the aircraft is' turning right, the bell will be to the left). Two possibilities for cor-recting this situation: either increase the bank angle or apply less rudder in the direction of the turn. .

A summary: • Balanced turn => needle will be deflected in the direction of the: turn; ball will be centered. • Slipping turn => both the needle and ball will be deflected in the direction of the turn. • Skidding turn => needle will be deflected in the direction of the

turn; ball will be deflected in the opposite side. Concerning the figure attached to the question: #1 represents a balanced left turn. #2 represents a slipping right turn (= insufficient right rudder/excessive right bank) #3 represents a skidding left turn (= too much left rudder/insufficient left bank) #4 represents a slipping left turn (= insufficient left rudder/excessive left bank)

271- A rate gyro is used in a: 1)directional gyro indicator 2)turn coordinator 3)artificial horizon

The combination regrouping all the correct statements is A)2 B)1,2,3 C)1

D)1,2 (Refer to figure 022-E27) Rate gyro - this is a gyro having freedom to rotate around only axis in addition to the spin axis. The axis

of freedom being 90 moved from the axis of rotation. It is utilised to measure rate of around the third axis and employs restraining springs

• The Turn Indicator has a horizontal rotor spin axis and freedom only 1 axis • The Artificial Horizon has a vertical rotor spin axis and freedom in 2 axis • The DGI (Directional Gyro Indicator) has a horizontal spin axis and freedom in 2axis. . Note: the degree of freedom of a gyro does not take into account . its rotor spin axis according to the JAA Learning Objectives. 272- The rate of turn given by the rate of turn indicator is valid:

A) for all airspeeds. B) for the airspeed range defined during the calibration of the instrument. C)with flaps retracted only. D) for the cruising speed.

(Refer to figures 022-£30 and 022-E31)

The Rate of turn" indicated on a Tum Indicator is a function of gyro tilt. Rate of turn is directly

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proportional to bank angle and inversely proportional to TAS (True Air Speed). It is completely independent of weight of the aircraft. The spin axis of the gyro is horizontal (parallel with the lateral axis of the aircraft) and is maintained in the horizontal by use of sensitive calibrated springs. As mentioned above, the rate of turn indication is a function of the gyro tilt. This tilt should be equal to the angle of bank in perfect conditions, therefore keeping the gyro axis horizontal. The magnitude of tilt is dependent on the rate of turn, but we know that the rate of turn depends on bank angle and TAS. Therefore, the gyro axis will stay 100% horizontal only in case of 1 value of TAS and this value is the one to which the instrument has been calibrated. At TAS values higher or lower than the calibrated one, the instrument will display a very slight error, which is however very small (typically only a few %).

273- The spin axis of the turn indicator gyro is aligned along the:

A) longitudinal axis of the aircraft. B) lateral axis of the aircraft. C) vertical axis of the aircraft. D) longitudinal axis of flight.

274-(Refer to figure 022-16) The diagram representing a left turn with insufficient rudder is:

A) 1 B) 2 C) 3 D)4

(Refer to figures 022-E30, 022-£31 and 022-£06) For the turn to be balanced (= no Slip & no Skid), the angle of bank must be appropriate for the TAS and the rate of turn used:

• Bank angle is excessive => aircraft is SLIPPING in and the ball is displaced to the inside of the turn

(for example, if the aircraft is turning right, the ball will be to the right). Two possibilities for correcting this situation: either reduce the bank angle or apply more rudder in the direction of the turn. • Bank angle is insufficient => aircraft is SKIDDING out and the ball is displaced to the outside of the

turn (for example, if the aircraft is turning right, the ball will be to the left). Two possibilities for correcting this situation: either increase the bank angle or apply less rudder in the direction of the turn.

A summary: ·Balanced turn => needle will be deflected in the direction of the turn; ball will be centered. • Slipping turn => both the needle. and ball will be deflected in the direction of the turn. • Skidding turn => needle will be deflected in the direction of the turn; ball will be deflected in the

opposite side.

Concerning the figure attached to the question: #1 represents a straight & level flight.

#2 represents a skidding left turn (= too much left rudder/insufficient left bank)

#3 represents a slipping right turn (= insufficient right rudder/excessive right bank)

#4 represents a slipping left turn (= insufficient left rudder/excessive left bank) 275-(Refer to figure 022-16)

The diagram representing a left turn with excessive rudder is: A) 1

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B) 2 C) 3 D) 4

276- The factors which will affect a Turn Indicator are: 1)angle of bank

2)aircraft speed 3)aircraft weight

A) all B) 1,2 C) 1,3 D)2,3

277- At a low bank angle, the measurement of rate-of-turn actually consists in measuring the:

A) roll rate. B) rate of yaw. C) angular velocity about the vertical axis. D) rate of pitch.

278- What angle of bank should you adopt on the attitude indicator for a standard rate (rate 1) turn while flying at an IAS of 130 kts?

A) 15°

B) 18° C) 20° D) 23°

An approximate calculation of the required angle of bank for Rate 1 turns is: Angle of bank = (TAS/10) + 7. Another formula that can be used is Bank angle = 15% of IAS. In our case we can use the second formula: 15% of 130 kts = 19,5° (200 being the closest answer possibility). 279- What is an operational difference between the turn coordinator and the turn and slip indicator?

A) The turn coordinator is always electric; the turn and slip indicator is always vacuum-driven.

B) The turn coordinator indicates bank angle only; the turn and slip indicator indicates rate of turn and coordination.

C) The turn coordinator indicates roll rate, rate of turn, and co-ordination; the turn and slip indicator indicates rate of turn and co-ordination.

D)The turn coordinator indicates angle of bank; the turn and-slip indicator indicates turn rate in coordinated flight.

280- The needle of the Turn and Bank indicator shows:

A) the bank angle at which the aircraft is turning about the roll axis. B)the rate at which the aircraft is turning about the yaw axis. C)the pitch angle during a turn. .

D)the rate at which the aircraft is rolling into a turn.

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281- The higher the airspeed is:

A) the higher the bank angle must be to turn at the standard rate. B)the lower the bank angle must be to turn at the standard rate. C)there is no relation between the speed and the rate of turn.

D)the higher the left or right rudder input must be to turn Fn a coordinated manner.

282- When an aircraft has turned 2700 with a constant attitude and bank, the pilot observes the following on a classic (air driven) artificial horizon:

A) too much nose up and bank too low. B) too much nose up and bank correct. C) too much nose up and bank too high. D) attitude and bank are correct.

(Refer to figures 022-E29 and 022-E30)

The artificial horizon suffers from both acceleration and turning errors: Acceleration errors - sometimes known as take-off errors, since they are most noticeable during this stage of flight. The tow components that introduce the errors are the pendulous unit and the vanes. In the air-driven instrument, the pendulous unit makes the rotor housing (inner gimbal) bottom-heavy. Thus, when the aircraft accelerates, a force due to the unit's inertia is effective at the bottom, acting aft towards the pilot. This force is precessed through 900 in an anti-clockwise direction, lifts up the right-hand side of the outer gimbal, and hence the sky-plate attached to the outer gimbal rotates anti-clockwise, indicating a false right turn on the bank angle index. During acceleration both longitudinally mounted side vanes are thrown back, with the result that the right side port opens and the port side closes; reaction occurs on the right side, precessed through 900, the reaction lifts the inner gimbal to indicate a false climb. In the case of the electrically driven gyro horizon, the inner gimbal does not have a pendulous: erection unit hanging below it and is therefore not Subject to apparent turn component of acceleration error. However, the mercury in the longitudinally mounted switch will hang back and complete the circuit to the pitch torque motor, causing the instrument to show a false climb. In summary, therefore, acceleration errors on the air-driven instrument result in an apparent climbing turn to the right being indicated, while the electrically driven instrument will show only a false climb in the same circumstances. Turning errors - during a turn the laterally mounted vanes of the air-driven gyro horizon erection mechanism will be displaced due to centrifugal force acting .outwards from the centre ot the turn. Thus one port will be open while the opposite port will be closed. Reaction will be set up in the fore and aft axis of the aircraft which, having precessed through 900, will lift the outer gimbal to the left or right. This results in a false bank indication. Centrifugal force also causes the pendulous unit to swing outwards away from the centre of the turn. The force affects the inner gimbal, giving a false indication of climb or descent. The combined effect of the two forces is to displace the gyro rotor in tow planes. In modem qyroscopes the gyro axis is off set from the true vertical to counter-act these errors, but the correction is only valid for a given rate of turn. The sale effect on an electrically driven gyro is to displace the mercury in the lateral mercury switch, to complete the circuit via one or other of the outer electrodes to the roll torque motor, resulting in a false bank indication. In summary, turning error will cause the air-driven gyro horizon to give a false indication of turn and climb or descent, while an electrically driven gyro will give only a false bank indication. Summary for Air-Driven Indicators: • Acceleration => apparent climbing turn to the right; • Deceleration => apparent descending turn to the left; • Turn through 900 => apparent climb; under-indication of bank; • Turn through 180' => apparent climb; correct bank indication; •Turn through 2700 => apparent climb; over-indication of bank;

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• Tum through 360' => both pitch and roll indicated correctly. Summary for Electrical-Driven Indicators: • Acceleration => apparent climb • Deceleration => apparent descent

Note: the above summary is valid for a gyro with rotor spinning counter-Clockwise as seen from above. Some units may have clockwise spinning rotors - in that case the errors are reversed. 283-During an acceleration phase at constant attitude, the resetting principle of the artificial horizon results in the horizon bar indicating a:

A) constant attitude . B) nose-down attitude. C) nose-up attitude. D) nose-down followed by a nose-up attitude.

284- Following 1800 stabilized turn with a constant attitude and bank, the artificial horizon (air driven) indicates:

A) too high pitch-up and too low banking. B) too high pitch-up and correct banking: C) attitude and banking correct.

D)too high pitch' up and too high banking. 285- When an aircraft has turned 360 degrees with a constant attitude and bank, the pilot observes the following on a classic (air driven) artificial horizon:

A) too much nose-up and bank too high. B) too much nose-up and bank too low. C) too much nose-up and bank correct. D)attitude and bank correct.

286- When an aircraft has turned 900 with a constant attitude and bank, the pilot observes the following on a classic (air driven) artificial horizon:

A) too much nose-up and bank correct. B) attitude and bank correct. C) too much nose-up and bank too low. D)too much nose-up and bank too high.

287-(Refer to figure 022-13) The diagram with shows a 300 right bank and 150 nose down attitude is:

A) 1 B)2

C)3 D)4

The attitude indicator illustrations shown in the attached figure have the following meaning: #1 = climbing turn to the left (pitched up) #2 = descending turn to the left (pitched down) #3 = climbing turn to the right (pitched up)

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#4 = descending turn to the right (pitched down) 288-(Refer to figure 022-15) The. diagram which shows a 400 left bank and 120 nose down attitude is number: .

A) 3 B)2 C)1 D)4

The indications on the artificial horizons in the picture are the following: #1 show 400 left bank and nose down #2 shows 20° left bank and nose down #3 shows 400 right bank and nose down #4 shows 40° left bank and nose up

289- During a deceleration phase at constant a ttitutie, the control system of an air driven artificial horizon results in the horizon bar indicating a:

A) nose up attitude. B) nose down attitude. C) constant attitude. D)nose up followed by a nose down attitude.

290- The gyroscope used in an attitude Indicator has a spin axis which is: A) horizontal, perpendicular to the yaw axis. B) horizontal, perpendicular to the longitudinal axis.

C) horizontal, parallel to the longitudinal axis. D) vertical.

291- When executing a turn by 900 at constant attitude and bank, a classic Artificial Horizon (air driven) indicates:

A) nose up and correct angle of bank. B) attitude and bank angle are correct. C) nose up and bank angle too low. D) nose up and bank angle too high.

292- Using a classic (air driven) Artificial Horizon, the aircraft performs a right 2700 turn at a constant angle of bank and rate of turn. The indication is:

A) nose up, too much bank. B) nose up, not enough bank. C) nose up, wings level. D)bank and pitch correct.

293-(Refer to figure 022_17) The instrument #1 presentation shows that the aircraft is (VSI reading zero):

A) pitched up. B) pitched down.

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C) in straight and level flight. D)pitched down and rolled to the left.

Both attitude indicators (artificial horizons) in the attached picture show a straight and level flight. The only difference between the two pictures is in the flight director command bars. In the picture #1 (top) the flight director command bars indicate that the pilot should pitch up and roll to the left to maintain the selected flight profile. In •the picture #2 (bottom) the flight director bars do not command any changes in the flight attitude to the pilot (== pilot is maintaining the desired flight profile - no pitch or roll changes are required). 294- Aircraft turns through 360" at constant bank and pitch angle. The Artificial Horizon (air driven) shows:

A) the correct indication. B) pitch up too little bank. C) pitch up too much bank. D) pitch up correct bank.

295-A gravity type erector is used in a vertical gyro device to correct errors on: . A) an artificial horizon. B) a directional gyro unit. C) a direct reading compass. D) a gyromagnetic indicator.

296- You have just taken off in a fast aircraft fitted with a vacuum operated attitude indicator. While climbing straight ahead - still accelerating - the instrument may for a short while indicate:

A) a high nose-up attitude. B) a flatter attitude than actual. C) a climbing turn to the left. D) a climbing turn to the right.

297- A direction gyro is corrected for accurate directional information using: A) air data computer. B) direct reading magnetic compass. C) flight director. D) flux valve.

Let's assume a typical non-slaved air-driven Directional Gyro Indicator (DGI). After the engine is started and the gyro has achieved its proper rotational speed, then as a part of the pre-takeoff checks

298-The stall warning system receives information about the: 1)airplane angle of attack 2)airplane speed 3)airplane bank angle 4)airplane configuration 5)load factor on the airplane

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The combination regrouping al/ the correct statements is A)1,2,3,4,5 B) 2,3,4,5 C)1,3,5 D)1,4

299- A stall warning system is based on measuring the:

A) attitude. B) TAS. C) angle of attack. D) ground speed.

300- Which of these signals are inputs, at least, in the stall warning computers? A) Angle of attack and flaps and spoilers deflection. B) Angle of attack and flaps and slats deflection. C) Angle of attack, flaps deflection and EPR. D) Angle of attack, flaps deflection, EPR and 1.

301- The data supplied by a radio altimeter: A) concerns only the decision height. B) indicates the distance between the ground and the aircraft. C) is used only by the radio altimeter indicator. D) is used by the automatic pilot in the altitude hold mode.

302- In low altitude radio altimeters, the height measurement (above the ground) is based upon:

A) a triangular amplitude modulation wave, for which modulation phase shift between transmitted and received waves after ground reflection is measured.

B) a pulse transmission, for which time between transmission and reception is measured on a circular scanning screen.

C) a wave transmission, for which the frequency shift by DOPPLER effect after ground reflection is measured.

D) a frequency modulation wave, for which the frequency variation between the transmitted wave and the received wave after ground reflection is measured.

303- A radio altimeter can be defined as a:

A) self contained on board aid used to measure the true height of the aircraft. .

B) ground radio aid used to measure the true altitude of the aircraft.

C) ground radio aid used to measure the true height of the aircraft.

D) self contained on board aid used to measure the true altitude of the aircraft.

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304-A radio altimeter is: A) ground based and measures true altitude. B) Ground based and measures true height. C) aircraft based and measures true altitude. D) aircraft based and measures true height.