Airmanship KnowledgeLearning Outcome 1Air Traffic Control

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Airmanship KnowledgeLearning Outcome 1

Understand the types of airfield operations used for the control of aircraft

Contents

• Control Towers• Controllers• Communication

Systems• Visual

Communications• RADAR• Approach Aids

Air Traffic Control

Introduction

On RAF Airfields all movements of aircraft, both on the ground and in the air are monitored by Air Traffic Control (ATC)

The Control Tower

• Is always in a prominent position in the aircraft manoeuvring area

• Houses electronic & radio equipment and may also have a Bird Control Unit

The Control Tower The size & design of ATC Towers varies considerably.

Aerodrome ControllerIs in charge of movements:Is in charge of movements:• On the GroundOn the Ground• In the AirIn the Air

Sometimes Called:Sometimes Called:• Airfield ControllerAirfield Controller• Local ControllerLocal Controller

On large airfields this is split in two as there is too much work for one person.On large airfields this is split in two as there is too much work for one person.

Aircraft movements on the ground up to the runway are controlled byAircraft movements on the ground up to the runway are controlled bya controller called Ground.a controller called Ground.

Aircraft movements on the runway and in the local area are controlledAircraft movements on the runway and in the local area are controlledby a controller called Tower.by a controller called Tower.

Approach Controller

They control aircraft:• departing the airfield • making instrument approaches

Both use RADAR displays, RT and landline communications

On light usage airfields On heavy usage airfieldsThe departures are separatedout under the Departures Controller

Runway Controller

For more effective control a Runway Controller may be used:

• At small airfields with lots of take-offs and landings

• They are in direct contact with Aerodrome/Local Controller

Runway ControllerThe Runway controller can refuse aircraft permission to move onto the runway, land or take-off in some circumstances

Runway Controller

For example they might:

• Prevent an aircraft from landing with its undercarriage retracted by firing a RED flare.

• Stop an aircraft from taking-off which had for example a panel unlocked or a fuel leak, by showing a steady RED on the signalling lamp.

Runway Controller

• Warn vehicles or aircraft on the ground to move clear of the landing area, by showing RED flashes on the signalling lamp.

• Give permission to take-off, with a steady GREEN on the signalling lamp.

Communication SystemsGood Communications are essential to Air Traffic Control

Communication Systems

Swift and accurate contact is achieved through the use of:•Special Telephones•Tele-Talk Systems•Radio Telephony (RT) (Ground To Air)

– Uses VHF and UHF to talk to aircraft and vehicles.– These frequencies provide clear lines of

communications.– Each airfield and its section have their own

frequencies.

Visual Communications

Stationary Object Hazard

Bad Ground Markers0.61 metressquare

Visual Communications

Helicopter Operating Areas:• The ‘H’ is 4 metres high by 2 metres across• It may also have a box around the ‘H’.• Well clear of fixed wing aircraft

OR

Radar

Stands For:

RAdio

Detection

And

Ranging

Radar

• Consists of a Transmitter and a Receiver

• A short pulse energy is transmitted from an aerial and the receiver “listens” for an echo.

Radar

• The receiver detects which reflections are from aircraft, and it can determine their position, direction of travel and speed.

• This information is then displayed through a cathode ray tube onto a screen. In this way radar has become the “eyes” of air traffic control

Radar Aids

The two main radar aids likely to be seen at Royal Air Force airfields are:

•Surveillance Radar

•Precision Approach Radar (PAR)

Surveillance Radar

Is used both to monitor air traffic passing through an area and as an airfield approach aid.

Surveillance Radar

Enables the controller to locate the aircraft and direct it to a position and height near the airfield

Surveillance Radar

Can be used for an airfield approach:

Surveillance Radar Approach (SRA)

The pilot hears directions to put him on the runway centreline and also heights that he should be passing every mile i.e.

“On runway centre line at 5 miles, should be passing1850Ft”

Precision Approach RadarThe controller has two screens, one for the aircraft’s elevation (height) and one for azimuth (left and right), relating to the approach path

Precision Approach Radar

The controller passes instructions by RT to the pilot to guide the aircraft down the correct glideslope and

centreline towards the touch-down point

The procedure is called a Ground Controlled Approach (GCA) or PAR Approach.The pilot hears directions to put him on the runway centreline and the ideal glidepath i.e.

“Left of centre line, come right 2 degrees, slightly low on glidepath, not correcting”

Precision Approach Radar

Precision Approach Radar

PAR 2000 Radar

Radio Aids

The two main Radio Aids likely to be seen at Royal Air Force airfields are:

•Digital Resolution Direction Finding (DRDF)

•Instrument Landing System (ILS)

DRDF• It is a common airfield approach aid at small airfields but

is seldom used at large busy airfields• It receives a carrier wave only transmission (no speech)

from an aircraft and displays it on a CRT as a green line called a “trace”.

• Enables the approach controller to tell the pilot what course to fly to the vicinity of the airfield for a visual approach

Instrument Landing System

ILS is a runway approach aid:

• Fixed transmitters on the ground send out a special pattern of radio signals

• These define a radio beam that is like a pathway in the sky

• The pathway then leads to the touch-down point on the runway

LocalizerTransmitter

GlidepathTransmitter

Runway

90Hz

150Hz

Glidepath

Instrument Landing System

ILS transmits 2 frequencies

Glidepath

90Hz signal is strongest, so aircraft is above the Glidepath

LocalizerTransmitter

GlidepathTransmitter

Runway

90Hz

150Hz

Glidepath

Instrument Landing System

Glidepath

ILS transmits 2 frequencies

150Hz signal is strongest, so aircraft is below the Glidepath

LocalizerTransmitter

GlidepathTransmitter

Runway

90Hz

150Hz

Glidepath

Instrument Landing System

Glidepath

ILS transmits 2 frequencies

Both signals are equal, so aircraft is on the Glidepath

LocalizerTransmitter

GlideslopeTransmitter

RunwayRunway Centre Line

90Hz

150Hz

Instrument Landing System

Localizer

ILS transmits 2 frequencies

90Hz signal is strongest, so aircraft is right of the Localizer

LocalizerTransmitter

GlideslopeTransmitter

RunwayRunway Centre Line

90Hz

150Hz

Instrument Landing System

Localizer

ILS transmits 2 frequencies

150Hz signal is strongest, so aircraft is left of the Localizer

LocalizerTransmitter

GlideslopeTransmitter

RunwayRunway Centre Line

90Hz

150Hz

Instrument Landing System

Localizer

ILS transmits 2 frequencies

Both signals are equal, so aircraft is on the Localizer

LocalizerTransmitter

GlideslopeTransmitter

RunwayRunway Centre Line

90Hz

150Hz

LocalizerTransmitter

GlidepathTransmitter

Runway

90Hz

150HzGlidepath

GPS Approach

Some airfields have been approved for GPS Approachesas long as the aircraft equipment has been approved.

The GPS Approach is flown on the same instruments as an ILS Approach and gives the same indications.

Questions?

WHICH BUILDING ON AN AIRFIELD HOUSES THE PEOPLEWHICH BUILDING ON AN AIRFIELD HOUSES THE PEOPLETHAT MONITOR AIRCRAFT ON THE GROUND AND IN THE AIR?THAT MONITOR AIRCRAFT ON THE GROUND AND IN THE AIR?

QUESTIONQUESTION

A.A. AIR TRAFFIC CO-ORDINATION ROOMAIR TRAFFIC CO-ORDINATION ROOM

B.B. AIRBORNE TRAFFIC CONTROL ROOMAIRBORNE TRAFFIC CONTROL ROOM

C.C. AIR TRAFFIC CONTROL TOWERAIR TRAFFIC CONTROL TOWERC.C. AIR TRAFFIC CONTROL TOWERAIR TRAFFIC CONTROL TOWER

D.D. AIR TRAFFIC CO-ORDINATION TOWERAIR TRAFFIC CO-ORDINATION TOWER

WHICH OF THE FOLLOWING WOULD NORMALLY WORK IN WHICH OF THE FOLLOWING WOULD NORMALLY WORK IN A GLASS WALLED ROOM IN A CONTROL TOWERA GLASS WALLED ROOM IN A CONTROL TOWER

QUESTIONQUESTION

A.A. PAR CONTROLLERPAR CONTROLLER

B.B. AIR CONTROLLER AIR CONTROLLER

C.C. APPROACH CONTROLLERAPPROACH CONTROLLER

D.D. AIRFIELD CONTROLLERAIRFIELD CONTROLLERD.D. AIRFIELD CONTROLLERAIRFIELD CONTROLLER

HOW DOES AN APPROACH CONTROLLER RECEIVEHOW DOES AN APPROACH CONTROLLER RECEIVEINFORMATION ABOUT AN AIRCRAFTINFORMATION ABOUT AN AIRCRAFT

QUESTIONQUESTION

A.A. RT, LANDLINE COMMUNICATIONS AND RADARRT, LANDLINE COMMUNICATIONS AND RADAR

B.B. RADAR ONLYRADAR ONLY

C.C. RT ONLYRT ONLY

D.D. RT AND LANDLINE COMMUNICATIONSRT AND LANDLINE COMMUNICATIONS

A.A. RT, LANDLINE COMMUNICATIONS AND RADARRT, LANDLINE COMMUNICATIONS AND RADAR

QUESTIONQUESTION

WHAT COLOURED SIGNAL WOULD BE USED BY A RUNWAY WHAT COLOURED SIGNAL WOULD BE USED BY A RUNWAY CONTROLLER TO CLEAR AN AIRCRAFT FOR TAKE-OFF ?CONTROLLER TO CLEAR AN AIRCRAFT FOR TAKE-OFF ?

A.A. A STEADY REDA STEADY RED

B.B. A FLASHING GREENA FLASHING GREEN

C.C. A FLASHING REDA FLASHING RED

D.D. A STEADY GREENA STEADY GREEND.D. A STEADY GREENA STEADY GREEN

QUESTIONQUESTION

HOW DOES THE CONTROLLER PASS PAR INSTRUCTIONSHOW DOES THE CONTROLLER PASS PAR INSTRUCTIONSTO THE PILOT ?TO THE PILOT ?

A.A. RTRT

B.B. RADARRADAR

C.C. MORSE CODEMORSE CODE

D.D. RF BEAMRF BEAM

A.A. RTRT

QUESTIONQUESTION

WHERE DOES THE PAR ALLOW THE PILOT TO GUIDE WHERE DOES THE PAR ALLOW THE PILOT TO GUIDE THE AIRCRAFT TO ?THE AIRCRAFT TO ?

A.A. TO THE DESIGNATED DISPERSAL AREATO THE DESIGNATED DISPERSAL AREA

B.B. TO THE CORRECT GLIDESLOPE AND CENTRELINETO THE CORRECT GLIDESLOPE AND CENTRELINE

C.C. TO AN AIRWAY IN CONTROLLED AIRSPACETO AN AIRWAY IN CONTROLLED AIRSPACE

D.D. TO THE TAKE-OFF POINTTO THE TAKE-OFF POINT

B.B. TO THE CORRECT GLIDESLOPE AND CENTRELINETO THE CORRECT GLIDESLOPE AND CENTRELINE

QUESTIONQUESTION

DRDF IS USED TO ?DRDF IS USED TO ?

A.A. DIRECT AN AIRCRAFT WHILE TAXYINGDIRECT AN AIRCRAFT WHILE TAXYING

B.B. DIRECT AN AIRCRAFT AFTER TAKE-OFFDIRECT AN AIRCRAFT AFTER TAKE-OFF

C.C. DIRECT AN AIRCRAFT TO THE VICINITY OF THE DIRECT AN AIRCRAFT TO THE VICINITY OF THE AIRFIELD FOR A VISUAL APPROACHAIRFIELD FOR A VISUAL APPROACH

D.D. DIRECT AN AIRCRAFT TO THE RUNWAY DIRECT AN AIRCRAFT TO THE RUNWAY TOUCHDOWN POINTTOUCHDOWN POINT

C.C. DIRECT AN AIRCRAFT TO THE VICINITY OF THE DIRECT AN AIRCRAFT TO THE VICINITY OF THE AIRFIELD FOR A VISUAL APPROACHAIRFIELD FOR A VISUAL APPROACH

QUESTIONQUESTION

AN ILS APPROACH IS USED TO ?AN ILS APPROACH IS USED TO ?

A.A. TALK AN AIRCRAFT ONTO THE CORRECT TALK AN AIRCRAFT ONTO THE CORRECT GLIDEPATH AND CENTRELINEGLIDEPATH AND CENTRELINE

B.B. FOLLOW ELECTRONIC SIGNALS ONTO THE FOLLOW ELECTRONIC SIGNALS ONTO THE CORRECT GLIDEPATH AND CENTRELINECORRECT GLIDEPATH AND CENTRELINE

C.C. APPROACH THE AIRFIELD FOR A VISUAL APPROACHAPPROACH THE AIRFIELD FOR A VISUAL APPROACH

D.D. DEPART THE AIRFIELDDEPART THE AIRFIELD

B.B. FOLLOW ELECTRONIC SIGNALS ONTO THE FOLLOW ELECTRONIC SIGNALS ONTO THE CORRECT GLIDEPATH AND CENTRELINECORRECT GLIDEPATH AND CENTRELINE

QUESTIONQUESTION

A GPS APPROACH IS DISPLAYED ON THE SAME A GPS APPROACH IS DISPLAYED ON THE SAME INSTRUMENTS AS ?INSTRUMENTS AS ?

A.A. A PARA PAR

B.B. A DRDFA DRDF

C.C. AN ILSAN ILS

D.D. AN SARAN SAR

C.C. AN ILSAN ILS