2009

Michelle Hancock

Max Gibson

Jenna Faulkner

Ben Semerjian

Portland State University

6/9/2009

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Table of Contents Introduction .................................................................................................................................................. 3

Design Challenge Background ....................................................................................................................... 4

Mission Statement and Design Requirements.............................................................................................. 5

Background Theory ....................................................................................................................................... 6

Brainstorming Ideas ...................................................................................................................................... 7

Design ............................................................................................................................................................ 8

Payload Box ............................................................................................................................................... 9

Materials ............................................................................................................................................... 9

Customizing ......................................................................................................................................... 13

Stabilizer .................................................................................................................................................. 19

Drag System ............................................................................................................................................ 20

Camera System ....................................................................................................................................... 23

Flight Procedure .......................................................................................................................................... 24

Launches ..................................................................................................................................................... 27

Conclusions ................................................................................................................................................. 30

Appendix A: FAA Regulations Regarding Unmanned Balloons ................................................................... 32

Appendix B: Supplier Information ............................................................................................................... 46

Appendix C: Carbon Fiber Arrow Shaft Stress Analysis ............................................................................... 48

Appendix D: Dragahedron........................................................................................................................... 50

Appendix E: Setting up the Canon A650 for LPSU’s Photography .............................................................. 55

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Figure 1: LPSU Mission 2 over Bend, Three Sisters Mountains, and Newberry Crater. The antenna boom is just visible at the top of the image.

Introduction Created in 2004 by Dr. Mark Weislogel, Launch PSU (LPSU) is an ongoing series of high altitude

balloon launches. Attaining elevations over 110,000 ft, LPSU has brought Portland State University to

new heights in academic community involvement, K-12 outreach, and visibility as only a few other

schools have managed to go higher.

Each year a new design or experiment is developed to increase knowledge of ballooning,

engineering or general science. The minimum payload contains: a camera programmed to automatically

take pictures during flight, a GPS to store location, and a radio for tracking purposes and to help find the

system after descent. For community outreach launches, such as the Lake Oswego Junior High missions,

student experiments including everything from ethylene glycol anti-freeze to cockroaches are flown as

well. Upon successful retrieval, the team acquires stratospheric images and experimental discoveries

that are shared with the school and community.

With the support of the NASA Oregon Space Grant Consortium, LPSU is offered as a

junior/senior level design class within the Mechanical and Materials Engineering (MME) department at

Portland State University. The 2009 design team includes MME seniors: Jenna Faulkner, Max Gibson,

and Michelle Hancock, as well as MME graduate student Ben Semerjian. Dr. Weislogel has continued to

serve as advisor, and launches are assisted by additional faculty members and alumni.

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Design Challenge Background Upon recovery, the LPSU Mission 11 was found in a jumbled heap. The parachute had not

deployed properly and was twisted in the remains of the ruptured balloon shown in Figure 2. The

payload had an impact velocity of 30 mph. The main dipole antenna was grounded, lawn dart fashion,

12 cm into the damp ground. The dog tracker antenna was on the bottom of the pile and grounded as

well. The expensive, heavy, and supposedly reliable “government” GPS never sent a single signal.

Luckily the package had landed only 0.25 mi from its last radioed location 49 seconds before touch down

when the battery in the main radio died. The single onboard camera had a lens error and failed to take

any pictures.

Figure 2: Mission 11 payload bundle near Warm Springs, Oregon. All antennae were grounded and the payloads were jumbled together with the balloon and parachute in a heap.

The design needed improvement. However, Mission 11 did clear the Cascade Mountain Range

to land near Warm Springs, Oregon. All parcels survived the impact, including Delilah, the cockroach.

The APRS radio was effective for tracking until the battery died, and the Dog Tracker was still active

upon recovery.

It was decided that the next PSU mission would have a longer flight time with a smaller payload.

A new design would be implemented to mitigate the descent complications that arose during Mission

11.

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Mission Statement and Design Requirements The objective of the 2009 Launch PSU team is to design, test and implement a novel stabilizing

system for the primary payload as well as an improved design for reducing the terminal velocity of the

package upon descent. An additional goal of the test flight is to capture as many high resolution images

as possible while exceeding the highest altitude recorded for Launch PSU mission of 113,012 ft.

All implemented systems must be an exception to the FAA’s unmanned balloon requirements as

listed in Appendix A. In addition a stabilizing system for the primary payload must:

Reduce spin of the payload

Add a minimal amount of weight

Add negligible risk to the balloon

Support at least 12lbs with a reasonable factor of safety in the case of additional

payloads

Either couple with the primary payload box

The terminal velocity reduction system must:

Be comparable in weight to the current parachute system at 130g

High reliability for positive deployment

Reduce the terminal velocity to an acceptable level

Highly visible for visual tracking as well as ground search during recovery

The launch will also incorporate a new GPS and an additional camera.

During the design process it was determined that the primary payload box would need to be

rebuilt to accommodate 2 cameras. The final design requirements for the primary payload box are:

Total weight should be less than or equal to 4 lbs

Adequate insulation to protect electronic components from an external temperature of

-60˚F

A heater, if necessary, to prolong battery life for the extended flight time

An evenly distributed load when suspended from a single central point

Exterior geometry in compliance with the FAA regulations regarding weight/size ratio

Couple with the stabilizing system

Exterior build material must be resilient enough to withstand 10 impacts

Exterior dimensions must be such that the drag force induced by the falling box reduces

the terminal velocity to less than or equal to the terminal velocity of the previous

control box

Interior dimensions to accommodate 2 A650 Canon Cameras at 180˚, the “government”

GPS transmitter unit, a small onboard GPS device, and an optional heater unit with

power supply.

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Background Theory High altitude balloon launches are governed by two physics concepts: buoyancy and drag.

Buoyancy allows the balloon to ascend while the drag aids in a successful descent for a low impact

landing.

Archimedes’ principle states that any object, wholly or partly immersed in a fluid, is buoyed up

by a force equal to the weight of the fluid displaced by the object. In this case, the fluid inside the

balloon is hydrogen while the fluid around the balloon is air. At standard temperature and pressure, the

air is about 14 times denser than hydrogen. This allows the balloon to float up.

Temperature and pressure change as the balloon ascends into high altitude. As seen in Figure 1,

air pressure decreases the as the balloon climbs. Temperature decreases overall as well. This natural

phenomenon also causes the hydrogen volume (i.e. the balloon volume) to also increase with altitude.

The decrease in air density allows hydrogen to expand. This expansion, along with the rapidly

decreasing temperatures as the balloon slowly climbs close to the upper atmosphere, causes the fragile

balloon to burst. At this point the payload begins its descent back to Earth.

Parachutes, streamers, and other designs used to slow a falling object all take advantage of drag. The

governing equation for drag force is:

𝐹𝑑 = −1

2𝜌𝑉2𝐴 𝐶𝑑

Where is the ρ density of the fluid, V is the velocity, A is the cross sectional area, and Cd is the drag

coefficient. The drag force must balance the weight of the object at terminal velocity. Thus:

𝑚𝑔 = −1

2𝜌𝑉𝑡𝑒𝑟𝑚𝑖𝑛𝑎𝑙

2𝐴 𝐶𝑑

Figure 3: Air pressure and temperature with respect to altitude. Image from CNES.

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Rearranging to solve for terminal velocity as a function of area, mass, and the drag coefficient results in:

𝑉𝑡𝑒𝑟𝑚𝑖𝑛𝑎𝑙 = 2𝑚𝑔

𝜌𝐴𝐶𝑑

Where m is the mass, g is the acceleration due to gravity, ρ density of the fluid, A is the cross sectional

area, and Cd is the drag coefficient.

At ground level the air density is 1.3 kg/m3 at standard temperature and pressure. Drag coefficients

are empirically determined. Table 1 displays pertinent drag coefficients for standard geometries.

Table 1: Drag Coefficients for various geometries.

Geometry Drag Coefficient

Cube 1.05

Angled Cube 0.80

Cone 0.50

Brainstorming Ideas The 2009 Launch PSU team brainstormed ideas before deciding on the final design idea. Alex

Baker and Donald Bell also contributed.

Parachute Alternatives:

Thermal Release: Balloon is released from payload by a heated wire, triggered by altitude

Hook: Residual spring release

Spring Accelerometer: Indicates the height to release balloon from payload

Thermal Embrittlement Shatter on Release: String that shatters with cold temperatures

Parachute Blossom: Parachute packed inside of balloon, only opening up when balloon bursts

Timed Electric: At a pre-programmed time, heated wire severs string between payload and

balloon

Razor Blade/Cutter: Mechanical cutter

Box Kite: Rigid parachute

Circliflex: Circular rigid parachute

Tetrahedron: Rigid parachute

Conical decelerator: Tip-side down rigid parachute

Enlarge Payload Box: Increases drag

Streamer(s): Packed inside balloon, increases drag of payload

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Balloon Yarmulke: Drogue parachute resting on top of balloon, already deployed

Second Balloon for Descent: Blow up second balloon for descent, with lower buoyant force than

the first

Netting/Paper Maché: Around balloon, skeleton of balloon for drag after it bursts

Payload Stabilizing Mechanisms:

Stiff Spring: Does not allow much twisting

Ladder Frame: Made of arrow shafts and kite joint components

Design After weighing the pros and cons for each brainstorming idea, the team agreed upon a design

with a rigid, tetrahedron parachute nicknamed “dragahedron” and a ladder frame for stabilization of the

payload box. Figure 4 displays a sketch of the concept design.

Figure 4: LPSU 12 Concept sketch with the dragahedron attached at the top of the primary payload box. An optional secondary payload would be attached at the bottom of the primary payload box for future missions.

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Payload Box

As mentioned previously, the payload box needed to be redesigned to fit the latest GPS and its required configuration. Critical components of the box redesign include material, geometry and weight.

Materials

Three foams were chosen to test and compare for the payload box. Foam is an optimal material to use for the high altitude payloads due to its weight, cost, accessibility and moisture-resistant, buoyant and thermal insulation properties.

The first foam chosen was typical 1.5” thick home insulation polystyrene foam found at Home Depot (Figure 5). This foam is also referred to as MEPS or Molded Expanded Polystyrene. MEPS white foam has large “grains” and is sold in large sheets. This material is very inexpensive (about $4 for enough material to construct the payload box), lightweight and has high R values typically ranging from R- 3.8 to R- 5.0 per inch.

Figure 5: MEPS foam after low pressure testing.

The second foam tested was a 2.5” thick blue polyethylene, which is similar to the material used to make pool noodles in the summer (Figure 6). It is denser than the MEPS foam, but offers greater flexibility and does not run the risk of flaking foam “grains.” This material is more expensive (totaling to about $17 for enough material to make the box) and was found at a store specializing in foam products in Portland (A1 Foam and Rubber).

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Figure 6: Polyethylene foam after low pressure testing.

The third foam was already constructed into a medical insulation box. The material is most similar to MEPS but with finer grains. The box was found in the LPSU Balloon lab and was likely to come from a source at OHSU. This box can be seen in Figure 7. The dimensions of the box, including the lid, are 14” L x 11.5” W x 11” H.

Figure 7: Medical insulation box found in the LPSU balloon lab.

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The ideal material for the payload box should be lightweight, be able to withstand impacts and can handle the temperature and pressure of the stratosphere up to 10 launches and landings. To best simulate the effects of the pressure cycles the payload experiences over multiple flights, the material was subjected to 10 cycles of a vacuum chamber. Each material was cut, carefully weighed and measured, and placed on a pre-marked platform inside the chamber. Observations were made about the expansion of the material during pressure cycles (Figure 8). Once the 10 cycles were complete, an overall volumetric measurement was made to evaluate the permanent deformation on the material along with an examination of how it held up.

Figure 8: Pressure Cycling MEPS and Polyethylene Foam

After pressure cycling the pre-made medical box fared the best. The MEPS foam material showed visible signs of deformation and compressed overall (Figure 5). While the blue foam did not compress overall, a time elapsed video during pressure cycling revealed a large amount of deformation during the cycling that would recover when the material returned to standard pressure. The medical box foam did not permanently deform or compress after the pressure cycles. Table 2 compares the densities and deformations of the three materials.

After looking at the test result data, it was determined that the medical insulation box suited the requirements for the payload box the best. Glued joints appeared too risky to have for a multiple-flight payload.

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Table 2: Material Deformation and Density Data.

Material Density (g/in^3)

Height Deformation

Height Deformation %

Width Deformation

Width Deformation %

White MEPS 0.186 31/32" to 0.0125"

1% 31/32" to 0.0125"

1%

Blue Polyethylene

0.450 2 1/8" to 2 3/8" 12% 2" to 2.025" 1%

Cooler MEPS 0.338 3/4" to 0.0125" 1% 9/16" to 0.0125"

1%

Along with the payload box materials, consideration for the glue that would join the foam together was considered. Gorilla Glue and 3M 90 Spray Adhesive were tested (Figure 9). Both are popular glues that can be found in national hardware stores. Each listed that the glue worked on “foams.” Two pieces the MEPS foam and blue polyethylene were glued to themselves with both glues (4 samples total). The glues were pressure cycled similar to the material test procedure above. These joints were also temperature tested by placing the materials in a sub-zero environment for a period of time. The samples were taken over to the Biology department and placed in a -80˚C for 40 minutes.

Figure 9: Gorilla Glue and 3M 90 Adhesive Glue were found to be ineffective.

Although Gorilla Glue held up when the sample was pulled, the samples immediately disbanded when turned in opposing directions. The 3M glue held in both pulling and torsion, but ended up “eating” the polyethylene. A third glue, Loctite, was found and passed testing for non-structural adhesion (Figure 10).

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Figure 10: Loctite resin and hardener used during box customization.

Customizing

Since the box chosen did not need to be constructed, the first steps to transforming the box from medical purposes to LPSU related activities included fitting all of the required instruments. Cuts were made to the box only after the box was balanced.

Fitting the large GPS was the most complicated step in customization. Although robust, its internal antenna can only send a signal when the GPS is right-side-up. There is no guarantee about which side the payload box will land once it hits the earth. If the GPS is upside-down, the team may not be able to get a signal and run the risk of permanently loosing the box. In order to mitigate this risk, the GPS is taped to an arrow shaft which is fitted into a collar on each end of the box (Figure 11). The box was scraped the sides with heat from a solder iron and X-Acto knives to ensure that the GPS can fully rotate to the correct position.

Figure 11: GPS in position. Duct tape is wrapped around entire GPS unit, including the arrow shaft.

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In the middle of the box are two structural supports made of arrow shafts that are insulated by foam. The arrow shafts extend down through the base of the box and up through the box lid. The purpose of the supports is for ease of assembly on launch day. After closing the payload, the stabilizer system will slide through the entire box with smaller diameter graphite kite poles, securing the system.

The arrow shafts were cut with a fine-tooth saw with masking tape wrapped around the cutting edge (Figure 12). The arrow shafts were permanently glued into the insulation foam by glue. Holes were cut in the top and the bottom of the box to accommodate the arrow shafts. To ensure free rotation of the large GPS, excess material was removed (Figure 13).

Figure 12: Cutting the arrow shaft with fine-tooth saw.

Figure 13: Completed supports.

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At the bottom of the box are two 6 inch long kite shaft feet are countersunk and glued to the bottom of the box. Each foot was cut in half and glued to a kite “T” joint. Another piece of kite shaft was run perpendicular through the bottom of the box and out through the other end. Holes were drilled at the end of these shafts to allow for a cotter pin (Figure 14).

Figure 14: Countersunk and glued feet.

The two cameras were placed 180 degrees from one another with the lenses pointing the opposite direction. Holes with approximately the same diameter of the lenses were cut on each side of the box with X-Acto knives. The area where the camera's batteries protrude into the foam wall was shaved back with a knife to comfortably fit (Figure 15). Excess material around the shutter button was removed to prevent disruption to the camera program. Weather stripping was applied around the lenses to prevent convective heat loss that would potentially cause pre-mature failure of the batteries (Figure 16).

Figure 15: Camera holes and placement.

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Figure 16: Lens in place with insulation filling air gaps.

A foam spacer was created to secure the cameras to the walls (Figure 17). The foam contains the resistive heater made of three 4.7Ω resistors connected to a 3V SAFT battery (Figure 18). The foam had two holes cut (one hole opening up to each camera) to allow the heater to prevent the camera batteries from freezing. The entire spacer was wrapped in a layer of packing tape to ensure smoothness and prevent wear.

Figure 17: Spacer containing heater.

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Figure 18: Resistive heater assembly with 3V battery.

Placed on top of the camera packed area is another fitted piece of foam that fills the dead space between the top of the cameras to the top of the box. A square hole was sized and cut to hold the small GPU in place (Figure 19). A foam “bridge” protects the GPS from any buttons accidentally being pushed during ascent, descent or landing.

Figure 19: Top spacer with small GPS tray.

Using a salvaged packaging shell, the 3V battery holder for the resistor heater was glued to the lid of the box over the large GPS (Figure 20). The GPS was verified for full rotation after the holder was

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attached. The opening of the shell faces outwards of the lid, making it easy to slide in the battery while the side of the box will hold the battery in place. The edges of the packaging shell were measured on the lid of the box. Using a knife, foam was cut out in the outline of the shell to allow it to “sink” into the box. This crevice was filled with glue along with the shell and attached.

Figure 20: 3V battery holder attached to lid of payload box.

The final weight of the payload box, with all of the components and tape, is 1.985 grams. This is under FAA requirements. Figure 21 displays the assembled payload box and its exploded view.

Figure 21: Fully assembled payload.

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Stabilizer Reduction of payload spin was a goal of the current launch design. The typical string-balloon connection

allows the balloon to rotate at roughly 0.3 Hz. While slow, it makes panorama photographs difficult to

obtain and potential contributes to image blur at lower altitudes. The balloon, however, is a very stable,

virtually irrotational, object. A rigid connection between payload and balloon will force them to obtain

the same rotation rate. This rate will not be as slight as the balloon, but it will be close—much lower

than the rotation rate typically experienced by the payload. As far as our literature search has

determined, a rigid connection has not been previously attempted on any balloon launch.

The stabilizer is made of two long arrow shafts that extend through a “double-H” harness

(Figure 22), through the payload box and pin underneath to mount the payload to the balloon. The

“double –H” harness tapes into the balloon nozzle. It offers greatly reduced pendulum effect over a

“single-H” design. A stress analysis of the rigid connection is in Appendix C.

Figure 22: Double-H connector with sample tubes shown. The actual stabilizer contains two 17” tubes.

Stock 0.22” diameter carbon tubes, kite connector joints, Loctite glue, and duct tape were used

for this build. Two 17” length shafts feed through a “double-H” connector. These shafts are

permanently pinned at the top and are removable, allowing them to be switched out with longer tubes,

if desired. This could allow for multiple payload boxes to be pinned together into a large rigid assembly.

The “double-H” connector comprises four rubber T-type kite connectors with two 1.75” segments

epoxied into the crossbars for support.

For bottom pinning after the payload is attached, proprietary patent-pending Maxloc™ fasteners

were created. These spring steel fasteners feature a quick feed, self locking design. An additional,

unnecessary layer of safety is provided by a quick-tightening Buntline hitch knot on a string holding the

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two fasteners together. Pulling one end (colored silver for ease of recognition) of the string tightens the

knot (Figure 23). Furthermore, the Buntline hitch gets tighter under a load. These two features make

accidental release of the payload virtually impossible.

Figure 23: String connecting two fasteners. Hold the knot while pulling the silver string to tighten.

Drag System The previous parachute had difficulty with deployment. Upon recovery of Mission 11, it was found that

the balloon had ruptured such that the parachute was entangled preventing it from effectively

deploying. For a new design to be competitive it needs to be similar in weight, more reliable, and have

similar drag characteristics to a conventional parachute.

A typical parachute is deployed at a certain altitude once a body is already falling. It is dependent on

friction to open and is sensitive to folding method. A bluff body drag unit circumvents these problems.

The unit always “open” and will provide the necessary drag regardless of its orientation relative to the

payload. The bluff body alternative will function properly even if the remnants of the balloon are

wrapped around it. There will be a slight affect on the rise rate of the balloon due to the increase in

drag, but this is likely to be negligible relative to the drag on the balloon.

Tetrahedron geometry encourages a stable orientation, and was selected for its symmetry. A prototype,

the “dragahedron“ shown in Figure 24, was built using six graphite arrow shafts and a medium weight

polyester fabric remnant.

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Figure 24: Dragahedron prototype made of polyester fabric and graphite arrow shafts. It is enclosed on all four sides, and length along an edge is 32 inches. The payload is attached at a single corner.

Initial testing was performed using the polyester prototype on Thursday May 7th. The prototype was

thrown from the Engineering Building roof on the north side of the building with a slight breeze out of

the SW. A total of three 100 ft drops were done. The first two drops had a fall time of approximately 10

seconds and did not have a payload attached. The third drop with a ~4 lb payload had a fall time of 4

seconds as determined by the video taken by Ben Semerjian. The velocity was approximately constant.

The prototype is heavier than the final design due to differences in fabric weight.

When attached to a payload the design was found to be very stable, and would “right” itself

with the payload falling first. Due to this inherent stability the final design was only enclosed on the

three downward sides reducing the total weight of the dragahedron. The final design, shown in Figure

25, was built using lightweight graphite arrow shafts and 0.5 oz polycarbonate coated rip-stop polyester.

For extra rigidity nylon string was threaded through each member. The string is also used as the

attachment point for the payload. Step by step build instructions and materials list are available in

Appendix (D). The final weight was 150 grams.

An experiment was conducted using a 2 lb payload. First just the payload was dropped ~85ft from the

landing on the stairway between the 4th and 5th floors of the Engineering Building. It fell in

approximately 2 seconds, same as a theoretical object with negligible drag. The payload was then

attached to the dragahedron and again dropped from the same height. The fall time of approximately 3

seconds calculated from a video of the event corresponds well with the theoretical value for the same

payload size of 2.91 seconds.

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Figure 25: Final dragahedron design ready for testing with a 2lb load.

The equation for terminal velocity as a function of area, mass, and the drag coefficient is:

𝑉𝑡𝑒𝑟𝑚𝑖𝑛𝑎𝑙 = 2𝑚𝑔

𝜌𝐴𝐶𝑑

Where m is the mass, g is the acceleration due to gravity, ρ density of the fluid, A is the cross sectional

area, and Cd is the drag coefficient. For the final design the values used for the calculated final velocity

are as follows: m = 5 lb = 2.25 kg, A = 443.4 in2 = 0.286 m2, Cd = 0.75, and ρ = 1.3 kg/m3 at standard

temperature and pressure. The expected terminal velocity is 12.5 m/s (41 ft/s or 28 mph).

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Camera System In the name of taking pretty pictures, every LPSU mission carries in its payload at least one camera

snapping photos by intervalometer. It's always been either a camera with a built in intervalometer or

else one externally controlled, however this year we decided to try something new.

It's no secret that for most of Canon's compact cameras an unofficial hack is available, known as CHDK

(Canon Hack Development Kit), which provides new features and allows scripting of the camera. We

decided to purchase two new cameras, the Powershot A650; this is a bigger compact camera (350 grams

with batteries). It was selected because it takes good quality pictures, offers sufficient manual control,

accepts SDHC cards, runs very long on four AA batteries, and has a tilting LCD screen which can be

conveniently shut to save power.

One new feature of this mission is that the cameras record RAW images, the camera natively can't do

this but CHDK allows it; RAW is preferred as it allows better adjustment of photos on a computer. More

interestingly, the camera is controlled by a Lua script run by CHDK. The script is responsible for both

taking photos on an interval and also for metering (selecting camera settings for proper exposure). The

function of the script breaks down as follows:

• Wait out a configurable initial delay, doing nothing so that the camera may be loaded into the

box.

• Take photos on the set shooting interval, metering for each picture in a special way.

• Log temperatures of the sensor, optic assembly, and batteries at every photo via thermistors

built into the camera.

The "special metering" mentioned above is different from the camera's metering, the implementation

uses concepts developed by Francesco Bonomi [footnote: http://www.francescobonomi.it/ballon-

photography-black-sky-metering], another CHDK user participating in balloon launches. The metering

works by:

• Before taking a photo, do a metering and save the calculated shutter speed (Tv) in a queue.

• Sort the queue and discard the 50% darkest and 10% brightest meterings.

• Average the remaining meterings and use that Tv for the current exposure.

The point of this is to ensure that the Earth is properly exposed. The 50% darkest meterings likely

involve a lot of black sky, which when properly exposed would result in the Earth being pure white in a

photo. The 10% lightest meterings likely involve the sun or a reflection of it. By avoiding these extremes

the Earth should be properly exposed every time. The numbers 50% and 10% are intended to be very

liberal, so that a lot of proper meterings fall into them. This is no problem since you really only need one

metering to take a picture.

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To prepare a camera for launch, a few settings are selected. An aperture value of f/4.0 is a good choice

since it allows sufficient light in and prevents to some degree chromatic aberration and the scare of

overexposure when very high and bright (unfortunately, this camera is not equipped with an ND filter).

The sensitivity is set to lowest: ISO 80. The focus is manual set to furthest. The script parameters are

setup.

With the camera otherwise ready, it's loaded with fresh batteries (we use Energizer Ultimate Lithium

batteries which reportedly go for 2000 pictures at room temperature). The camera is switched on, the

script started, the camera loaded into the payload box.

Flight Procedure The following is a step-by-step guide to assembling the payload for launch.

1. Duct tape the large GPS to the rotating shaft. The head of the GPS goes toward the “R” side of

the payload box.

2. Cut a notch in the duct tape over the red tab. This will allow you to pull red tab later to activate

the GPS.

3. Place the two columns into the bottom of the box. The one labeled “L” goes on the “L” side of

the box. The one labeled “R” goes on the “R” side of the box. If properly aligned, you will see

arrows on the columns pointing to arrows on the box.

4. Place the resistor cage component of the heater into the camera spacer. Run the wire

connecting the resistors through the silver door on the “M” side of the box.

5. Put battery into battery compartment on the underside of the lid. Be sure it is a new battery.

Run the connector through the notch labeled “cord.”

6. Turn on the cameras and start the preloaded photo program.

7. Place cameras in the box. The “L” camera goes on the “L” side of the box. The other camera

goes on the “R” side of the box. Check that the seal around the lens collar and the box holes is

appropriate. If weather stripping around the lens collar has been removed or fallen off, it may

need to be reapplied.

8. Press camera spacer between the two cameras. The “L” side goes on the “L” side of the box, the

“R” side goes on the “R” side of the box, the “M” side goes on the “M” side of the box, and the

“G” side goes on the “G” side of the box. If properly assembled, the heater wire should be

coming out on the “M” side of the box, between the camera spacer and the columns.

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9. Place the top spacer above the cameras, “up” side up. The “L” side goes toward the “L” side of

the box, and the “R” side goes toward the “R” side of the box.

10. Turn small GPS on and place into corresponding hole in the top spacer. The buttons should not

be under the white foam hood.

11. Activate the heater by connecting the resistor wires to the battery.

12. Slide lid on top of box, aligning the arrows on the lid with those on the box. Press down gently to

ensure a proper fit between the columns and the corresponding holes in the lid. Tape the lid

down to ensure a seal. The tape serves no structural purpose.

13. The stabilizer (both the “double-H” and the long tubes—and the descent control device!) should

already be taped to the balloon nozzle and the balloon is likely ‘hanging out’ while you assemble

the box. Pull the balloon back in and slide the poles through the holes in the box. There are

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some very slight misalignments that might require a bit of wiggling to get the poles through. You

should not have to force it!

14. With one person holding the balloon and another person holding the box, someone will pin the

bottom, using the proprietary patent-pending Maxloc™ fasteners. It’s not a bad idea to practice

the fastening prior to launch day. While the fasteners and string are revolutionarily easy to use,

some practice is necessary to determine the procedure. (Pin through the hole, push all the way,

and rotate so that the tube is encircled. Repeat with other fastener and tube. Hold the knot on

the string while pulling the silver lead. The string will tighten. The fasteners are immobile.)

15. Release the payload and the balloon will take off.

Launch PSU 13 2009

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Launches Three of the 4 team members participated in Mission 12: Lake Oswego Jr. High IV. The balloon was

released to overcast gray skies at approximately 8:15 am June 8th from the west field of the Jr. High.

Although this launch used the same procedure and equipment as previous launches, it was an excellent

opportunity for this team to participate in a launch and identify possible complications with the newly

developed payload box and dragahedron. In addition to the APRS radio and dog tracker locating

methods, the payload also included the proprietary “government” GPS.

Under mild wind conditions, the balloon ascended roughly 20,000 ft before following the jet stream to

the southwest. According to the APRS radio, it reached a maximum height of 110,522 ft before rupture

of the balloon. The lift package touched down on the roof of a building at the Aurora Airport, and was

recovered by an individual working there. The flight path is shown in Figure 26.

Figure 26 Flight path of Mission 12: Lake Oswego Jr. High IV June 8th 2009. The straight line between Wilsonville and the Aurora airport is due to a packet received out of sequence.

Launch PSU 13 2009

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Advisor Dr. Mark Weislogel, and team: Yongkang Chen, Donald Bell, Jenna Faulkner, Michelle

Hancock, Max Gibson, and Ben Semerjian, met at 4:30am on Thursday June 11th for the scheduled dawn

release of Mission 13 from the roof of Portland State University Parking Structure 1. The lift package

included the dragahedron, dog tracker, and new control box holding 2 Canon cameras, “government”

GPS, heater, and small data recorder GPS. The total weight was 5.23 lb, and the balloon had

approximately 2.5 lb of free lift. Although 2 tanks of hydrogen were available only most of one tank was

used.

The balloon was released at 5:57am on June 11th. It was retrieved at approximately 9:00am

from a tree south of Forest Grove, OR. The flight path is shown in Figure 28. The large points are the

“pings” sent by the “government” GPS, the smaller path is the data from the onboard location storage

GPS.

Figure 27: Flight path of Mission 13. Large points are the locations relayed by the "government" GPS, the thinner path is composed of the data recorded by the smaller GPS.

Upon retrieval, the dragahedron showed no damage, and the control box only sustained minor

damage. One of the large GPS swivel mounts had disengaged from the side of the box. The cameras

operated as planned, and all electronic components were operational (aside from expired batteries)

upon retrieval. The heater was still warm, and may have actually been “too” warm. Figure 28 shows a

panorama composed by Ben Semerjian of photographs taken during Mission 13.

Launch PSU 13 2009

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Figure 28: Cloudscape composed by Ben Semerjian

The data was compiled from the WBT-201 non-transmitting GPS. A hard ceiling was found to

occur at 107,000 ft. This is very disappointing as the projected height from the rest of the data puts the

maximum height between 120,000 and 124,000 ft, well above LPSU’s record of 113,000 ft. Figure 30

shows plots of altitude versus time for the balloon, as well as the predicted maximum height.

Figure 29: Altitude versus time for Mission 13, with detail of predicted maximum height.

During preliminary testing, the dragahedron has shown to follow a stable orientation when

loaded as shown in Figure 30. The drag induced by the dragahedron should result in a terminal velocity

of 12.5 m/s (28 mph). This calculation does not include drag from the balloon remnants or primary

control box, thus the actual terminal velocity experienced by the payload should be slightly slower.

0

20,000

40,000

60,000

80,000

100,000

120,000

140,000

4:48 5:16 5:45 6:14 6:43 7:12 7:40

Alt

itu

de

(ft)

time (PST, not PSD)

80,000

90,000

100,000

110,000

120,000

130,000

140,000

6:14 6:28 6:43 6:57 7:12 7:26

Alt

itu

de

(ft)

time (PST, not PSD)

5min dwellwindow

Launch PSU 13 2009

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Figure 30: Schematic of lift package during descent.

When the data was reduced it was found that the terminal velocity was approximately 2400

ft/min (about 27 mph or 12 m/s). The dragahedron performed as expected.

Conclusions Both launches were successful in that they were retrieved and took wonderful pictures. It is regrettable

that the Junior High student experiments were lost. To prevent this in the future, all knots should be

double checked and if are found questionable should either be re-tied or reinforced with duct tape.

The “government” SX1 GPS has performed better than in previous launches, but lacks the instant

gratification of the APRS tracking system. With the APRS system, data is relayed at a faster rate

providing the opportunity for enhanced flight path prediction. Also APRS does not have the “hard

ceiling” of the WBT-201 non-transmitting GPS.

The balloon was wrapped around the connecting string as expected, but not around the dragahedron.

The terminal velocity is unknown as the data received from GPS recorder has yet to be reduced. If the

terminal velocity is considered to be “too high” the dragahedron geometry could be modified.

Increasing the angle at the apex of the tetrahedron, as well as the length of the base, would increase the

drag area thus reducing the terminal velocity. The 0.5 oz polycarbonate coated rip-stop polyester

performed well, but either fluorescent orange or fluorescent pink should be used instead. Fluorescent

green was somewhat difficult to spot in a forested area.

The primary payload box needs minor repair, but could certainly be used for additional flights. There

were some concerns that the pins located at the top of the rigid mount system would damage the

balloon, but the duct tape wrapped around them was sufficient. The balloon followed a typical rupture

pattern and there was no sign of fatigue in the contact area near the mount.

Launch PSU 13 2009

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The cameras performed well. An increase in the downward angle of the cameras would decrease the

visibility of the balloon in some of the pictures.

Figure 31: Image from Mission 13. The balloon is slightly visible at the top of the photograph.

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Appendix A: FAA Regulations Regarding Unmanned Balloons The FAA Regulations from the National Archives and Records Administration Website

http://ecfr.gpoaccess.gov/cgi/t/text/text-

idx?c=ecfr&sid=ea968eea871ed9ab2380f6d979eaa7a6&rgn=div5&view=text&node=14:2.0.1.3.15&idno

=14#14:2.0.1.3.15.1.9.1

e-CFR Data is current as of June 8, 2009

Title 14: Aeronautics and Space

PART 101—MOORED BALLOONS, KITES, UNMANNED ROCKETS AND UNMANNED FREE

BALLOONS

Section Contents

Subpart A—General

§ 101.1 Applicability.

§ 101.3 Waivers.

§ 101.5 Operations in prohibited or restricted areas.

§ 101.7 Hazardous operations.

Subpart B—Moored Balloons and Kites

§ 101.11 Applicability.

§ 101.13 Operating limitations.

§ 101.15 Notice requirements.

§ 101.17 Lighting and marking requirements.

§ 101.19 Rapid deflation device.

Subpart C—Unmanned Rockets

§ 101.21 Applicability.

§ 101.22 Definitions.

§ 101.23 General operating limitations.

§ 101.25 Operating limitations for Class 2—High-Power Rockets.

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§ 101.26 Operating limitations for Class 3—Advanced High-Power Rockets.

§ 101.27 ATC notification for all launches.

Subpart D—Unmanned Free Balloons

§ 101.29 Information requirements.

§ 101.31 Applicability.

§ 101.33 Operating limitations.

§ 101.35 Equipment and marking requirements.

§ 101.37 Notice requirements.

§ 101.39 Balloon position reports.

Authority: 49 U.S.C. 106(g), 40103, 40113–40114, 45302, 44502, 44514, 44701–44702, 44721, 46308.

Subpart A—General

§ 101.1 Applicability.

(a) This part prescribes rules governing the operation in the United States, of the following:

(1) Except as provided for in §101.7, any balloon that is moored to the surface of the earth or an

object thereon and that has a diameter of more than 6 feet or a gas capacity of more than 115

cubic feet.

(2) Except as provided for in §101.7, any kite that weighs more than 5 pounds and is intended to

be flown at the end of a rope or cable.

(3) Any unmanned rocket except aerial firework displays.

(4) Except as provided for in §101.7, any unmanned free balloon that—

(i) Carries a payload package that weighs more than four pounds and has a weight/size ratio of

more than three ounces per square inch on any surface of the package, determined by dividing

the total weight in ounces of the payload package by the area in square inches of its smallest

surface;

(ii) Carries a payload package that weighs more than six pounds;

(iii) Carries a payload, of two or more packages, that weighs more than 12 pounds; or

(iv) Uses a rope or other device for suspension of the payload that requires an impact force of

more than 50 pounds to separate the suspended payload from the balloon.

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(b) For the purposes of this part, a gyroglider attached to a vehicle on the surface of the earth is

considered to be a kite.

[Doc. No. 1580, 28 FR 6721, June 29, 1963, as amended by Amdt. 101–1, 29 FR 46, Jan. 3,

1964; Amdt. 101–3, 35 FR 8213, May 26, 1970; Amdt. 101–8, 73 FR 73781, Dec. 4, 2008]

§ 101.3 Waivers.

No person may conduct operations that require a deviation from this part except under a

certificate of waiver issued by the Administrator.

[Doc. No. 1580, 28 FR 6721, June 29, 1963]

§ 101.5 Operations in prohibited or restricted areas.

No person may operate a moored balloon, kite, unmanned rocket, or unmanned free balloon in a

prohibited or restricted area unless he has permission from the using or controlling agency, as

appropriate.

[Doc. No. 1457, 29 FR 46, Jan. 3, 1964]

§ 101.7 Hazardous operations.

(a) No person may operate any moored balloon, kite, unmanned rocket, or unmanned free

balloon in a manner that creates a hazard to other persons, or their property.

(b) No person operating any moored balloon, kite, unmanned rocket, or unmanned free balloon

may allow an object to be dropped therefrom, if such action creates a hazard to other persons or

their property.

(Sec. 6(c), Department of Transportation Act (49 U.S.C. 1655(c)))

[Doc. No. 12800, 39 FR 22252, June 21, 1974]

Subpart B—Moored Balloons and Kites

Source: Docket No. 1580, 28 FR 6722, June 29, 1963, unless otherwise noted.

§ 101.11 Applicability.

This subpart applies to the operation of moored balloons and kites. However, a person operating

a moored balloon or kite within a restricted area must comply only with §101.19 and with

additional limitations imposed by the using or controlling agency, as appropriate.

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§ 101.13 Operating limitations.

(a) Except as provided in paragraph (b) of this section, no person may operate a moored balloon

or kite—

(1) Less than 500 feet from the base of any cloud;

(2) More than 500 feet above the surface of the earth;

(3) From an area where the ground visibility is less than three miles; or

(4) Within five miles of the boundary of any airport.

(b) Paragraph (a) of this section does not apply to the operation of a balloon or kite below the top

of any structure and within 250 feet of it, if that shielded operation does not obscure any lighting

on the structure.

§ 101.15 Notice requirements.

No person may operate an unshielded moored balloon or kite more than 150 feet above the

surface of the earth unless, at least 24 hours before beginning the operation, he gives the

following information to the FAA ATC facility that is nearest to the place of intended operation:

(a) The names and addresses of the owners and operators.

(b) The size of the balloon or the size and weight of the kite.

(c) The location of the operation.

(d) The height above the surface of the earth at which the balloon or kite is to be operated.

(e) The date, time, and duration of the operation.

§ 101.17 Lighting and marking requirements.

(a) No person may operate a moored balloon or kite, between sunset and sunrise unless the

balloon or kite, and its mooring lines, are lighted so as to give a visual warning equal to that

required for obstructions to air navigation in the FAA publication ―Obstruction Marking and

Lighting‖.

(b) No person may operate a moored balloon or kite between sunrise and sunset unless its

mooring lines have colored pennants or streamers attached at not more than 50 foot intervals

beginning at 150 feet above the surface of the earth and visible for at least one mile.

(Sec. 6(c), Department of Transportation Act (49 U.S.C. 1655(c)))

Launch PSU 13 2009

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[Doc. No. 1580, 28 FR 6722, June 29, 1963, as amended by Amdt. 101–4, 39 FR 22252, June

21, 1974]

§ 101.19 Rapid deflation device.

No person may operate a moored balloon unless it has a device that will automatically and

rapidly deflate the balloon if it escapes from its moorings. If the device does not function

properly, the operator shall immediately notify the nearest ATC facility of the location and time

of the escape and the estimated flight path of the balloon.

Subpart C—Unmanned Rockets

§ 101.21 Applicability.

(a) This subpart applies to operating unmanned rockets. However, a person operating an

unmanned rocket within a restricted area must comply with §101.25(b)(7)(ii) and with any

additional limitations imposed by the using or controlling agency.

(b) A person operating an unmanned rocket other than an amateur rocket as defined in §1.1 of

this chapter must comply with 14 CFR Chapter III.

[Doc. No. FAA–2007–27390, 73 FR 73781, Dec. 4, 2008]

§ 101.22 Definitions.

The following definitions apply to this subpart:

(a) Class 1—Model Rocket means an amateur rocket that:

(1) Uses no more than 125 grams (4.4 ounces) of propellant;

(2) Uses a slow-burning propellant;

(3) Is made of paper, wood, or breakable plastic;

(4) Contains no substantial metal parts; and

(5) Weighs no more than 1,500 grams (53 ounces), including the propellant.

(b) Class 2—High-Power Rocket means an amateur rocket other than a model rocket that is

propelled by a motor or motors having a combined total impulse of 40,960 Newton-seconds

(9,208 pound-seconds) or less.

(c) Class 3—Advanced High-Power Rocket means an amateur rocket other than a model rocket

or high-power rocket.

Launch PSU 13 2009

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[Doc. No. FAA–2007–27390, 73 FR 73781, Dec. 4, 2008]

§ 101.23 General operating limitations.

(a) You must operate an amateur rocket in such a manner that it:

(1) Is launched on a suborbital trajectory;

(2) When launched, must not cross into the territory of a foreign country unless an agreement is

in place between the United States and the country of concern;

(3) Is unmanned; and

(4) Does not create a hazard to persons, property, or other aircraft.

(b) The FAA may specify additional operating limitations necessary to ensure that air traffic is

not adversely affected, and public safety is not jeopardized.

[Doc. No. FAA–2007–27390, 73 FR 73781, Dec. 4, 2008]

§ 101.25 Operating limitations for Class 2—High-Power Rockets.

(a) You must comply with the General Operating Limitations of §101.23.

(b) In addition, you must not operate a Class 2—High-Power Rocket—

(1) At any altitude where clouds or obscuring phenomena of more than five-tenths coverage

prevails;

(2) At any altitude where the horizontal visibility is less than five miles;

(3) Into any cloud;

(4) Between sunset and sunrise without prior authorization from the FAA;

(5) Within 8 kilometers (5 statute miles) of any airport boundary without prior authorization

from the FAA;

(6) In controlled airspace without prior authorization from the FAA;

(7) Unless you observe the greater of the following separation distances from any person or

property that is not associated with the operations applies:

(i) Not less than one-quarter the maximum expected altitude;

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(ii) 457 meters (1,500 ft.);

(8) Unless a person at least eighteen years old is present, is charged with ensuring the safety of

the operation, and has final approval authority for initiating high-power rocket flight; and

(9) Unless reasonable precautions are provided to report and control a fire caused by rocket

activities.

[Doc. No. FAA–2007–27390, 73 FR 73781, Dec. 4, 2008]

§ 101.26 Operating limitations for Class 3—Advanced High-Power Rockets.

You must comply with:

(a) The General Operating Limitations of §101.23;

(b) The operating limitations contained in §101.25;

(c) Any other operating limitations for Class 3—Advanced High-Power Rockets prescribed by

the FAA that are necessary to ensure that air traffic is not adversely affected, and public safety is

not jeopardized.

[Doc. No. FAA–2007–27390, 73 FR 73781, Dec. 4, 2008]

§ 101.27 ATC notification for all launches.

No person may operate an unmanned rocket other than a Class 1—Model Rocket unless that

person gives the following information to the FAA ATC facility nearest to the place of intended

operation no less than 24 hours before and no more than three days before beginning the

operation:

(a) The name and address of the operator; except when there are multiple participants at a single

event, the name and address of the person so designated as the event launch coordinator, whose

duties include coordination of the required launch data estimates and coordinating the launch

event;

(b) Date and time the activity will begin;

(c) Radius of the affected area on the ground in statute miles;

(d) Location of the center of the affected area in latitude and longitude coordinates;

(e) Highest affected altitude;

(f) Duration of the activity;

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(g) Any other pertinent information requested by the ATC facility.

[Doc. No. FAA–2007–27390, 73 FR 73781, Dec. 4, 2008]

Subpart D—Unmanned Free Balloons

Source: Docket No. 1457, 29 FR 47, Jan. 3, 1964, unless otherwise noted.

§ 101.29 Information requirements.

(a) Class 2—High-Power Rockets . When a Class 2—High-Power Rocket requires a certificate

of waiver or authorization, the person planning the operation must provide the information below

on each type of rocket to the FAA at least 45 days before the proposed operation. The FAA may

request additional information if necessary to ensure the proposed operations can be safely

conducted. The information shall include for each type of Class 2 rocket expected to be flown:

(1) Estimated number of rockets,

(2) Type of propulsion (liquid or solid), fuel(s) and oxidizer(s),

(3) Description of the launcher(s) planned to be used, including any airborne platform(s),

(4) Description of recovery system,

(5) Highest altitude, above ground level, expected to be reached,

(6) Launch site latitude, longitude, and elevation, and

(7) Any additional safety procedures that will be followed.

(b) Class 3—Advanced High-Power Rockets . When a Class 3—Advanced High-Power Rocket

requires a certificate of waiver or authorization the person planning the operation must provide

the information below for each type of rocket to the FAA at least 45 days before the proposed

operation. The FAA may request additional information if necessary to ensure the proposed

operations can be safely conducted. The information shall include for each type of Class 3 rocket

expected to be flown:

(1) The information requirements of paragraph (a) of this section,

(2) Maximum possible range,

(3) The dynamic stability characteristics for the entire flight profile,

(4) A description of all major rocket systems, including structural, pneumatic, propellant,

propulsion, ignition, electrical, avionics, recovery, wind-weighting, flight control, and tracking,

Launch PSU 13 2009

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(5) A description of other support equipment necessary for a safe operation,

(6) The planned flight profile and sequence of events,

(7) All nominal impact areas, including those for any spent motors and other discarded hardware,

within three standard deviations of the mean impact point,

(8) Launch commit criteria,

(9) Countdown procedures, and

(10) Mishap procedures.

[Doc. No. FAA–2007–27390, 73 FR 73781, Dec. 4, 2008]

§ 101.31 Applicability.

This subpart applies to the operation of unmanned free balloons. However, a person operating an

unmanned free balloon within a restricted area must comply only with §101.33 (d) and (e) and

with any additional limitations that are imposed by the using or controlling agency, as

appropriate.

§ 101.33 Operating limitations.

No person may operate an unmanned free balloon—

(a) Unless otherwise authorized by ATC, below 2,000 feet above the surface within the lateral

boundaries of the surface areas of Class B, Class C, Class D, or Class E airspace designated for

an airport;

(b) At any altitude where there are clouds or obscuring phenomena of more than five-tenths

coverage;

(c) At any altitude below 60,000 feet standard pressure altitude where the horizontal visibility is

less than five miles;

(d) During the first 1,000 feet of ascent, over a congested area of a city, town, or settlement or an

open-air assembly of persons not associated with the operation; or

(e) In such a manner that impact of the balloon, or part thereof including its payload, with the

surface creates a hazard to persons or property not associated with the operation.

[Doc. No. 1457, 29 FR 47, Jan. 3, 1964, as amended by Amdt. 101–5, 56 FR 65662, Dec. 17,

1991]

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§ 101.35 Equipment and marking requirements.

(a) No person may operate an unmanned free balloon unless—

(1) It is equipped with at least two payload cut-down systems or devices that operate

independently of each other;

(2) At least two methods, systems, devices, or combinations thereof, that function independently

of each other, are employed for terminating the flight of the balloon envelope; and

(3) The balloon envelope is equipped with a radar reflective device(s) or material that will

present an echo to surface radar operating in the 200 MHz to 2700 MHz frequency range.

The operator shall activate the appropriate devices required by paragraphs (a) (1) and (2) of this

section when weather conditions are less than those prescribed for operation under this subpart,

or if a malfunction or any other reason makes the further operation hazardous to other air traffic

or to persons and property on the surface.

(b) No person may operate an unmanned free balloon below 60,000 feet standard pressure

altitude between sunset and sunrise (as corrected to the altitude of operation) unless the balloon

and its attachments and payload, whether or not they become separated during the operation, are

equipped with lights that are visible for at least 5 miles and have a flash frequency of at least 40,

and not more than 100, cycles per minute.

(c) No person may operate an unmanned free balloon that is equipped with a trailing antenna that

requires an impact force of more than 50 pounds to break it at any point, unless the antenna has

colored pennants or streamers that are attached at not more than 50 foot intervals and that are

visible for at least one mile.

(d) No person may operate between sunrise and sunset an unmanned free balloon that is

equipped with a suspension device (other than a highly conspicuously colored open parachute)

more than 50 feet along, unless the suspension device is colored in alternate bands of high

conspicuity colors or has colored pennants or streamers attached which are visible for at least

one mile.

(Sec. 6(c), Department of Transportation Act (49 U.S.C. 1655(c)))

[Doc. No. 1457, 29 FR 47, Jan. 3, 1964, as amended by Amdt. 101–2, 32 FR 5254, Mar. 29,

1967; Amdt. 101–4, 39 FR 22252, June 21, 1974]

§ 101.37 Notice requirements.

(a) Prelaunch notice: Except as provided in paragraph (b) of this section, no person may operate

an unmanned free balloon unless, within 6 to 24 hours before beginning the operation, he gives

the following information to the FAA ATC facility that is nearest to the place of intended

operation:

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(1) The balloon identification.

(2) The estimated date and time of launching, amended as necessary to remain within plus or

minus 30 minutes.

(3) The location of the launching site.

(4) The cruising altitude.

(5) The forecast trajectory and estimated time to cruising altitude or 60,000 feet standard

pressure altitude, whichever is lower.

(6) The length and diameter of the balloon, length of the suspension device, weight of the

payload, and length of the trailing antenna.

(7) The duration of flight.

(8) The forecast time and location of impact with the surface of the earth.

(b) For solar or cosmic disturbance investigations involving a critical time element, the

information in paragraph (a) of this section shall be given within 30 minutes to 24 hours before

beginning the operation.

(c) Cancellation notice: If the operation is canceled, the person who intended to conduct the

operation shall immediately notify the nearest FAA ATC facility.

(d) Launch notice: Each person operating an unmanned free balloon shall notify the nearest FAA

or military ATC facility of the launch time immediately after the balloon is launched.

§ 101.39 Balloon position reports.

(a) Each person operating an unmanned free balloon shall:

(1) Unless ATC requires otherwise, monitor the course of the balloon and record its position at

least every two hours; and

(2) Forward any balloon position reports requested by ATC.

(b) One hour before beginning descent, each person operating an unmanned free balloon shall

forward to the nearest FAA ATC facility the following information regarding the balloon:

(1) The current geographical position.

(2) The altitude.

(3) The forecast time of penetration of 60,000 feet standard pressure altitude (if applicable).

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(4) The forecast trajectory for the balance of the flight.

(5) The forecast time and location of impact with the surface of the earth.

(c) If a balloon position report is not recorded for any two-hour period of flight, the person

operating an unmanned free balloon shall immediately notify the nearest FAA ATC facility. The

notice shall include the last recorded position and any revision of the forecast trajectory. The

nearest FAA ATC facility shall be notified immediately when tracking of the balloon is re-

established.

(d) Each person operating an unmanned free balloon shall notify the nearest FAA ATC facility

when the operation is ended.

---------------------------------------------------------------------------------------------------------------------

---------------------------------------------------------------------------------------------------------------------

The FAA response protocol for flights of unmanned balloons from

http://www.faa.gov/airports_airtraffic/air_traffic/publications/atpubs/FAC/Ch18/s1805.html

U.S. DEPARTMENT OF TRANSPORTATION FEDERAL AVIATION ADMINISTRATION

ORDER JO 7210.3V

Effective Date: February 14, 2008

Subject: Facility Operation and Administration

Includes Change 1 Effective July 31, 2008 and Change 2 effective March 12, 2009

Section 5. Moored Balloons, Kites, Unmanned Rockets, and Unmanned

Free Balloons/Objects

18-5-1. MOORED BALLOONS, KITES, UNMANNED ROCKETS, AND UNMANNED

FREE BALLOONS/OBJECTS

Apply the following guidelines to moored balloon, kite, unmanned rocket, or unmanned free

balloon flights conducted in accordance with Part 101 of 14 CFR:

a. Facilities receiving moored balloon, kite, unmanned rocket, or unmanned free balloon

information shall ensure that appropriate notices include the information required by 14 CFR

Sections 101.15, 101.37, and 101.39.

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b. Notice information shall be forwarded to affected air traffic facility/s. Also, air traffic

facilities shall forward notices received to the appropriate AFSS/FSS for dissemination as a

NOTAM.

c. Handle unmanned free balloon operations below 2,000 feet above the surface in Class B,

Class C, Class D or Class E airspace areas requiring ATC authorization as follows:

1. Authorize the request if the operation is not expected to impact the normally expected

movement of traffic.

2. Coordinate with other affected facilities before authorizing the flight.

d. Request the operator of unmanned free balloon flights to forward position reports at any time

they are needed to assist in flight following.

NOTE-Operators are required only to notify the nearest FAA ATC facility if a balloon position

report is not recorded for 2 hours. Other position reports are forwarded only as requested by

ATC.

18-5-2. DERELICT BALLOONS/OBJECTS

Take the following actions when a moored balloon/object is reported to have escaped from its

moorings and may pose a hazard to air navigation, the operator of an unmanned free balloon

advises that a position report has not been recorded for a 2-hour period, or the balloon's/object's

flight cannot be terminated as planned:

a. Determine from the operator the last known and the present estimated position of the

balloon/object as well as the time duration that the balloon/object is estimated to stay aloft.

Also obtain other information from the operator such as the operator's access to a chase

plane, hazardous material onboard, balloon/object coloring, special lighting, etc.

b. Attempt to locate and flight follow the derelict balloon/object.

c. Determine if the balloon's/object's flight can be terminated by the operator. If the

balloon's/object's flight can be terminated, inform the operator of any known air traffic that

might be a factor.

d. If the balloon's/object's flight cannot be terminated:

1. Advise the operator that the balloon/object is declared to be a derelict and as such is a

potential hazard to air navigation.

2. Notify the ATCSCC, the regional Operations Center, and all affected facilities of the

derelict. The ATCSCC will serve as the focal point for the collection and

dissemination of further information.

3. Provide the ATCSCC with revised position or altitude information.

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4. If required, assistance in locating and tracking the balloon may be requested from the

National Military Command Center (NMCC), NORAD, or other agencies with

surveillance capabilities through the ATCSCC. If appropriate, the ATCSCC will

advise the NMCC that the derelict balloon is a current or potential hazard to air

traffic. If the balloon cannot be located or flight followed, it poses at least a potential

hazard.

NOTE-The final decision to destroy the derelict balloon is the responsibility of the appropriate

NORAD Commander.

e. Record and handle the derelict balloon as a Miscellaneous Incident.

REFERENCE-

FAAO JO 7110.65, Para 9-6-2, Derelict Balloons.

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Appendix B: Supplier Information “Government” GPS: SX1 GPS transmitter

“Small” GPS: Wintec WBT-201 GPS

Cameras: Two Canon Powershot A650 digital cameras, with hack

MEPS foam: building insulation foam purchased at Home Depot, Portland, OR

Polyethylene foam: packing material type foam purchased at A-1 Foam Rubber, Portland, OR

Graphite Arrow Shafts: by Gold Tip, minimum order of 12

Graphite kite shafts: purchased at Banner and Flag, Hollywood District, Portland, OR

Kite connector pieces: purchased by previous LPSU team from The Kite Shop, Vancouver, WA (was

found to be closed June 2009)

Fabric: 0.5 Oz Poly carbonate coated rip-stop Polyester,$ 9.95 per yard (40” wide), Hang-em High Fabrics

Richmond, VA

Alternate Suppliers for Insulated Shipping Containers, besides surplus donated containers from OHSU.

Neither prices nor material specifications were checked, but it's something to look at. There is always

the option of having a custom shape done, if at some point LPSU perfected a design.

http://www.coldice.com/insulated_shipping_containers.html

http://www.armstrongbrands.com/store.asp?pid=9009

http://www.fastpack.net/Shopping.idc?ProductCategory=21

http://www.cincinnatifoamproducts.com/

http://www.fast-pack.com/insulated-shipping-containers.html

http://www.thermalsystems.com/

http://www.achfoam.com/InsulatedShippingContainers.aspx

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Alternate Suppliers for light weight fabric, usually made for kites, sails, ultra-light aircraft, and outdoor

equipment such as tents and stuff sacks. Also tips for sewing light weight fabrics and material

specifications.

http://ecom.citystar.com/hang-em-high/ushop/index.cgi?ID=EKZ11W&task=show&cat=FABRIC

http://www.rcgroups.com/forums/showthread.php?t=82950

http://www.goodwinds.com/goodwinds/merch/list.shtml?cat=fabric

http://www.kitebuilder.com/techsheets/Fabrictech.htm

http://books.google.com/books?id=BKTuTXrXQu0C&pg=PA258&lpg=PA258&dq=0.5+oz++nylon+fabric&

source=bl&ots=n_qkyq3PYn&sig=WH7CKABzcvCGOeF9bwwEjgEEeRk&hl=en&ei=ZRIcStuaEJKKtgOX7aXa

CA&sa=X&oi=book_result&ct=result&resnum=2

http://www.geocities.com/gengvall/sew/sew.html

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Appendix C: Carbon Fiber Arrow Shaft Stress Analysis

Bending stress on GPS rotation pole:

𝜍 = 𝑀𝑐/𝐼

𝑀 =0.439

4.43= 0.0991 𝑙𝑏𝑓 − 𝑖𝑛

𝑐 =7.3

64= 0.114 𝑖𝑛

𝐼 =𝜋

4 𝑟𝑜

4 − 𝑟𝑖4 = 0.00202 𝑖𝑛4

𝜍 =0.0991 ∗ 0.114

0.00202= 5.6 𝑝𝑠𝑖

Tensile stress limit (from http://graphitestore.com/pop_up_grades.asp?gr_name=GR-CFR)

200 ksi (tensile)

9800 psi (shear)

Shear stress (Table 3-2 in Shigley, 8th ed.)

𝜏 =2 ∗ 𝑉

𝐴

𝐴 =𝜋

4 𝑟𝑜

2 − 𝑟𝑖2 = 0.0315 𝑖𝑛2

𝑉 =𝑊

2=

0.878

2= 0.439 𝑙𝑏𝑓

𝜏 =2 ∗ 0.439

0.0315= 27.9 𝑝𝑠𝑖

Both stresses are well under the limit.

0.878 lbf

0.439 lbf 0.439 lbf

4.43 in 7.3/32 in 3.5/32 in

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Tensile stress in poles:

𝐹 =𝑊

2=

4.3 𝑙𝑏𝑓

2= 2.15 𝑙𝑏𝑓

𝐴 =𝜋

4 𝑟𝑜

2 − 𝑟𝑖2 = 0.0315 𝑖𝑛2

𝜍 =𝐹

𝐴= 68.3 𝑝𝑠𝑖

This is under the limit of 200 ksi.

13.9 in

1.22 in

3.5 in

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Appendix D: Dragahedron

To Build the Dragahedron

Materials:

0.5 Oz Poly carbonate coated rip-stop Polyester

$ 9.95 per yard (40” wide)

Hang-em High Fabrics Richmond, Va

http://ecom.citystar.com/hang-em-high/ushop/index.cgi?ID=BJXYEE

32” Gold Tip Ultralight arrow shafts series 22 Diameter 0.337 “

Cost?

Supplier

Website

Coats & Clark cotton-poly all purpose thread

Nylon String Weight?

Tools:

Sewing Machine: capable of plain straight stitch with tension adjusted correctly for the material,

stitching off-set guide, and sharp #12 needle

Matches

Sharp scissors

Layout Chalk or similar

Large flat surface

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Procedure:

1. Read all instructions and notes before starting.

2. Layout and cut as shown in figure 1. The seam allowances are included.

3. Stitch casings for the first 2 poles. Stitching should be 15mm from the edge with a stitch length

of 2mm. These casings will be fitted for the shafts.

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4. Stitch the two raw sides together right sides together. Stitch 5mm from the edge.

5. Fold along stitching and fold to one side, stitch near folded edge.

6. Turn right side out, and stitch casing as for others.

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7. Along raw bottom sections fold up 30mm and stitch 15mm from the edge. Stop about 50mm

from each end.

8. Insert all shafts into their casings.

9. Feed string through as shown.

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10. Tie off ends and melt with matches to prevent unraveling, and rotate so knots are inside the

shafts.

11. Tie last knot in the top for attachment loop.

12. Complete finish stitching as needed by hand.

13. Finished dragahedron

Build Notes:

Polycarbonate coated polyester will hold a slight crease if pressed by hand. Do not use heat as

this will melt the fibers together. The fabric is rather stiff like heavy tissue paper and does not drape. It

is somewhat slippery, and feeds best if supported with both hands. The coating does prevent raveling

along raw edges, and limits stretch along the bias.

The rip-stop grid is not dependably orthogonal; do not use it for layout. The fabric used for the

first build was approximately 2˚ greater than square which corresponds to an offset of 1” at 30”.

Test the fit of each casing as finished instead of waiting until the end.

The bottom string should be fairly tight with only enough play to slide knot back into the shaft.

The side string loops should each have an extra 12” in length for the top loop.

For finish stitching a back stitch works well. A prick stitch pulls out. A whip stitch tends to tear the

fabric due to the concentrated load along an unfinished edge.

Some testing for fabric integrity was done. It took two people pulling as hard as they can to pull out the

fabric along the seam for a smaller stitch length. The stitching did not rip out for the stitch length used.

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Appendix E: Setting up the Canon A650 for LPSU’s Photography

Note that opening the little rubber cover on the side exposes a jack that says "DC In 4.3" V. But we'll use

proper AA cells for now, the awfully expensive Energizer Ultimate Lithium no less.

Setting camera up from factory settings:

Set date/stuff. Do be accurate, try setting according to the US official time (search "the time" on

the internet).

Go to Menu->Tools

Mute: On

Start-up Image: Off

Power Saving:

Auto Power Down: Off

Display Off: 3 min.

Auto Rotate: On

Power camera on to manual mode (M), and:

Set zoom to whatever it'll be on flight, probably widest.

Press Func Set and set the lowest image qualities: compression to Normal and size to

640x480.

Press Display a couple times so the screen info is always active (else it goes eventually).

Set manual focus to infinity. Double check that the pictures are sharply focused at this

setting!

Then press Menu:

Digital Zoon: Off

MF-Point Zoom: Off

Safety MF : Off

AF-assist Beam: Off

IS Mode: Off

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Save Settings->OK

That last step saves all these settings to the custom mode (C), even the manual focusing

(you want it furthest for high altitude pictures).

So when you set the dial to (C), everything is as setup above even if you change stuff in (M).

This is nice because you probably want full image size/quality in (M), among other things.

Make sure you do NOT assign the shortcut key for anything.

The natural as-Canon-intended camera is all setup. Now we'll put CHDK on it to screw around with it on

a lower level.

Install CHDK which includes my configuration settings and the script, all ready to go. Just unrar

AllSetupReadyToGoCHDK.rar to the card's main directory using a card reader, two files (DISKBOOT.BIN

and PS.FI2) and a subdirectory called CHDK will be created, in CHDK is SCRIPTS which contains lpsu.lua,

the script we use.

Or, if you want the latest, go download the complete CHDK, and copy it to the card. There is no need to

format the card or anything, and any size SD or SDHC card should work. The CHDK instructions are

slightly out of date as of this writing, they may say something like "use a 4 gb or smaller SD card and lock

the card", this is wrong and locking the card isn't necessary (it is true for autoloading which we won't

do). Then put our configuration settings CCHDK.CFG and script lpsu.lua in it.

CHDK without autoloading must be manually loaded every time the camera is powered on. Set the

camera into play mode, turn it on, press menu, press up to highlight Firm Update, and apply the

"firmware update". CHDK is now loaded and its functions accessible via the shortcut key.

I customize CHDK quite a bit also, including disabling the splash screen and basically all of the OSD

except sensor temperature and RAW state. These settings are all saved in the file CCHDK.CFG. Script

settings are accessible by pressing the shortcut button and then Func Set. The camera will remember

your settings.

The main important CHDK setting to change is enabling RAW save (Shortcut key->Raw parameters->Save

RAW). A note on these raw files: you can't view/delete them in camera, you must load the files (CRW

extension) onto a computer using a card reader. You know the camera is saving RAW when it takes an

extra 3 or so seconds to save a picture, with the blue shortcut light on.

With the camera all setup as above, the procedure for using the camera in a balloon flight is:

Set the mode dial to (C).

Put the camera in Play mode (switch on the back), turn the camera on, and load CHDK via Firm

update in the menu.

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Put the camera in Record mode, the lens should extend.

Start the CHDK script: press the shortcut button and then press the shutter.

Shut the LCD so that it turns off, saving much power.

Put the camera in the balloon and get on with your life.

The aperture and sensitivity aren't controlled by the script. You probably want f/4 at lowest sensitivity

ISO80. Note that raising the sensitivity has the same effect as raising the exposure of a RAW file on the

computer, really you should stick to ISO80 and if low sensitivity bothers you implement a minimum

shutter speed. White balance isn't a concern with RAW either.