EOSS Handbook Chapter 2

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  • 2.1. FAA rules
  • 2.1.1. Applicability of FAA Regulations to unmanned free balloons
  • 2.1.2. Operating Limitations
  • 2.1.3. Equipment and Marking
  • 2.1.4. Notification requirements 4
  • 2.1.5. EOSS policy 4
  • 2.2. The Ground Station 4
  • 2.2.1. Introduction 4
  • 2.2.2. Equipment 4
  • Packet 5
  • Amateur TV (ATV) 5
  • Radios 5
  • Antenna Systems 5
  • Plotting 5
  • Miscellaneous 5
  • 2.2.3. Location 6
  • 2.2.4. Setup Schedule 6
  • 2.2.5. Operations 6
  • At T-60 minutes 6
  • At T-10 minutes 6
  • At Launch 6
  • At T+n minutes 6
  • End of Flight Preparations 6
  • Descent Phase 7
  • Preparing for LOS 7
  • LOS 7
  • 2.3. Balloons 7
  • 2.3.1. Reference 7
  • 2.3.2. Terminology 7
  • 2.3.3. Site preparations 7
  • 2.3.4. Handling balloons 7
  • 2.3.5. Handling helium 8
  • 2.4. Launch Team 8
  • 2.4.1. Launch Director 8
  • 2.4.2. Balloon Lead 9
  • 2.4.3. Payload Lead 9
  • 2.4.4. Ground Station Lead 9
  • 2.4.5. Tracking and Recovery Lead 9
  • 2.5. Launch commit criteria 9
  • 2.5.1. Launch Checklist 9
  • 2.5.2. GO/NO-GO decisions 9
  • 2.5.3. Launch Team member roles 9
  • 2.5.4. Weather 10
  • 2.5.5. FAA requirements 10
  • 2.5.6. Final launch decision 10
  • 2.6. Launch sequence 10

2. Launch

2.1. FAA rules

<<Jack Crabtree>> Operation of unmanned free balloons is covered under Part 101, Subchapter F, Air Traffic and General Operating Rules, of Title 14 of the Code of Federal Regulations. In all cases, operation of an unmanned free balloon may not create a hazard to other persons or their property. The EOSS balloon team is well acquainted with the particulars of the FAA regulations and insures that all EOSS projects are in full compliance with these regulations. Careful adherence to all FAA requirements is mandatory for safe balloon operations and continued cooperation of the FAA. Basically, regulations provide for three categories of balloon payloads by weight; up to 4 pounds, those between 4 and 6 pounds, and those six pounds and greater.

2.1.1. Applicability of FAA Regulations to unmanned free balloons

  • Payloads up to 4 pounds in weight are basically exempt from the regulations.
  • Payloads weighing between 4 and 6 pounds are exempt from the regulations if certain weight-density requirements are met: weigh less than 3 ounces per square inch along smallest side.
  • For a single payload weighing above 6 pounds, a number of requirements apply. These include operating limitations such as maximum permissible cloud cover, equipment and marking requirements, formal notification, and position reporting during flight.
  • For a payload consisting of two or more packages weighing more than 12 pounds.

2.1.2. Operating Limitations

  • In a control zone below 2,000 feet unless authorized by Air Traffic Control.
  • Any altitude where clouds are more than 50%.
  • Over a congested area for the first 1,000 feet.
  • Where impact may create a hazard to persons or property.

2.1.3. Equipment and Marking

  • Two independent cut-down systems
  • Two independent methods to terminate flight of balloon
  • Radar reflective device
  • Night operations require lights
  • Suspension device greater than 50 feet requires color pennants.
  • Parachute must be highly conspicuously colored

2.1.4. Notification requirements

  • Pre-launch: 6-24 hours
  • At launch
  • Cancellation if required
  • Position reports, geographical and altitude as required
  • Derelict status if control is lost
  • Touchdown

2.1.5. EOSS policy

  • Full compliance
  • For small payloads (less than 6 pounds), use single cut-down
  • Notify FAA as a courtesy
  • Do not create a hazardous situation

These are only a few of requirements you may be facing. You should read and understand the regulations.

2.2. The Ground Station

2.2.1. Introduction

<<Rick von Glahn>> You've all heard the words, "Johnson Space Center, the mission control center personnel are slowly turning blue in the face." when our astronauts said, "Houston, Tranquillity Base here. The Eagle has landed." Cheers go up and people start their respiration processes once again. It's exhilarating to have your hard worked plans come to fruition and in today's balloon community scenes like that one are often repeated. Granted, we at Edge of Space Sciences, Inc. (EOSS) are not quite in the same league as NASA, and our flights aren't quite so perilous as Apollo 11. Nevertheless, cheers are often heard at our mission control station when onlookers view our controlled cut down of the payload from it's balloon. The ground station on EOSS flights serves the same purpose as mission control in Houston does for NASA flights. We monitor the telemetry, and control the payload.

2.2.2. Equipment

The ground station can be as simple as a two meter hand held receiving a beacon (on really simple flights) and as complicated as several receiving stations displaying packet data, Amateur Television, beacons, information and GPS data, a transmitter sending up commands to the payload to control the amateur TV (ATV) camera's angle of view, activate heating elements, and actuating the cut down system.

The following is a typical list of equipment: Packet

  • Yaesu FT470 to receive packets and transmit commands.
  • KPC-3 Packet TNC Compac 3/25 laptop computer
  • Okidata Microline 92 printer
  • Computer paper
  • Spare ribbon
  • 30 watt amp to ensure we can talk to the payload.
  • Various serial and parallel cables to connect the packet station together Amateur TV (ATV)

  • ATV down converter
  • VCR - taping the flight
  • Blank tape
  • (2) 19-inch TVs (one for ground station personnel, the other for visitors to the station). Radios

Two Meter
  • Icom HT - Launch site intercom
  • Icom 2410H - Interact with transmitter hunters in the field via repeaters
  • HF Transceiver Antenna Systems

  • 2 meter 12 element yagi beam antenna - receives packets and transmits commands to payload
  • 70 centimeter 22 element yagi beam antenna with pre-amp- receives ATV from payload
  • 40 meter dipole antenna - located at least 100 yards away from Control site to minimize electromagnetic interference to computer systems, used to communicate with fox hunters should they leave the coverage area of all available repeater systems
  • Several Mag Mount Antennas used for voice communication to various groups in the field
  • Antenna Rotor - Antennas remotely located atop a building. The tripod mounted azimuth and elevation Rotors enable quick antenna repositioning from the ground station
  • Several hundred feet of coax to connect the remote beam antenna systems Plotting

  • Plotting board
  • Overlay grid
  • Colorado Recreational road map
  • Aviation plotter calibrated to the CO Rec. Road Map
  • Aviation sectional maps for latitude and longitude determination
  • Plotting markers (sharp and non permanent)
  • Cellular Phone - used to maintain liaison with the Federal Aviation Administration keeping them apprised of the progress of our payload Miscellaneous

  • 120 VAC power or a generator capable of running all your gear
  • (2) 6-outlet power strips
  • AC 150 ft. of heavy duty outdoor AC extension cord
  • 120 VAC to 12 VDC at 20 Amp power supply
  • Duct tape
  • Soldering station
  • Iron
  • Solder
  • Dikes
  • 12 volt power strip
  • Cigarette lighter adapters
  • Banana plugs
  • Spare fuses
  • 75 ohm splitter
  • Tripod & 2 meter beam (used for distant repeaters)
  • Multimeter
  • SWR meter
  • Junk BOX - contains lots of, what else, junk
    • For example:
    • BNC to PL-259 converters
    • N to BNC
    • PL-259 to BNC
    • Wire
    • Batteries
    • Nuts and bolts
    • Lots of tools
    • and more junk!!
    • Tables
    • Chairs

2.2.3. Location

Although EOSS almost always locates its ground station at the launch site, it doesn't have to be done that way. Just as Kennedy Space Center in Florida controls the launch of space flights and Johnson Space Center in Texas controls the in flight operations, EOSS or any group could operate the same way. A balloon quickly rises above the local terrain and can be controlled by stations several miles away. From that point on, the communications window to the balloon steadily increases until the moment of cut down.

One proviso here. While the launch team is getting the payload ready for flight, they need to be able to verify operations of all systems aboard. If the ground station is located at a distant site and unable to receive the payload while it is on the ground, the launch site will need a mini ground station to verify operations of all the systems aboard the payload. This essentially means a duplicate of all systems at the ground station with the exception of the high gain antenna systems needed to communicate with the payload over great distances.

2.2.4. Setup Schedule

A typical ground station setup usually starts about two to three hours prior to launch. All members of the ground station team assemble at the designated spot and start plugging all that equipment together. The objective of the set up team is to be up and operating at a minimum one hour prior to launch. Even the most experienced team can find itself short of one vital piece of equipment that is either forgotten, or damaged in transit to the operation site. Checklists are invaluable.

2.2.5. Operations At T-60 minutes

At one hour before lift off, the ground station goes on the air. By then it has verified operation of all it's components and is in a position to report on the payload status as indicated by the various beacons, packet systems and ATV transmissions. The launch team uses this information to verify their launch preparations. At T-10 minutes

At T-10 minutes we start recording data and video. A continuous hard copy of the packet telemetry is printed and used by the plotting team, also located at launch site, to locate the position of the balloon. At Launch

At launch the ground station team takes over control from the launch team. All commands to the payload are sent from this station until Loss of signal (LOS) (minutes before landing usually) when a field team member takes over. At T+n minutes

During the flight the ground station receives the telemetry, plots the position of the payload, controls the camera, and relays information of interest to transmitter hunter field teams. This is the "fun" time for ground station personnel. It's their bird to play with. We usually cater to the whims of spectator gallery with regard to camera views showing what ever interests the crowd. If we detect icing on any of our servo systems, we can activate heating elements aboard the payload.

The Federal Aviation Administration (FAA) is often involved in our fights. They may require that we report our position at various altitudes on the way up and down. We assign a ground station team member to act as liaison to the FAA. It is that team member's sole responsibility to monitor the flight and report to the FAA when each reporting criteria is met. End of Flight Preparations

Prior to launch a cut down altitude is determined. When the balloon ascends to within 10,000 feet of that altitude, the ground team goes into "serious" mode. Once the balloon is near cut down altitude the camera is turned down to show a last view of the ground from maximum altitude. The horizon is then viewed.

At 100,000 feet altitude it's an impressive sight. The sky is completely black. The atmosphere shows as a band of gray (b&w camera) above the horizon and the horizon is ever so slightly curved. Finally we pan the camera up to look at the balloon and parachute. This angle of view is maintained during the cut down procedure to offer absolute verification of a successful release of the payload.

When the balloon reaches it's maximum altitude, we send the arming signal to the cut down mechanism, and then actuate the system to release the payload from the balloon. This is the most dramatic moment of the flight. We definitely want to release the balloon from the payload. When balloons explode, they have been known to foul the shroud lines of the parachute system, producing a faster than anticipated descent and subsequent hard landing. Everyone gets that blue in the face look as the code is entered. Then, voila, the balloon sails away as the payload drops. Almost immediately the parachute inflates and we're on our way down. Descent Phase

During the descent phase, the ground station continues to monitor and relay tracking information to the field teams. Camera views are again at the request of the experimenter or the gallery. Preparing for LOS

Once the payload has descended to 10,000 feet above what we estimate will be the loss of signal (LOS) altitude for the ground station the camera is pointed at the ground. It stays in that position for the remainder for the flight. On several flights views of unique ground features that were of help to the recovery team have been obtained. At this point the ground station's job is essentially over. Naturally, everything from the balloon until LOS is monitored. Contact is maintained with the field teams even after LOS should they require any data that has been collected. LOS

Once LOS occurs, dismemberment of the ground station commences. Everything not related to communications with field teams is taken down and packed up into waiting vehicles.

2.3. Balloons

2.3.1. Reference

<<Merle McCaslin>> One of the references we use is: Basic Procedures For Small Balloon Flights, 1976 put out by the Office of Naval Research. In general, the Navy works with much larger balloons (payloads to 150 lbs.), but the reference is very good for anyone flying balloons.

2.3.2. Terminology

  • Tare Weight: The tare weight is equivalent to the weight of the equipment to be lifted + Free Lift.
  • Free Lift = 0.10 to 0.25 x (payload + balloon weight)
  • Gross Inflation = Payload + balloon weight + Free lift
  • Gross Weight = Total airborne weight, exclusive of lifting gas
  • Total airborne weight = balloon weight + payload weight.

2.3.3. Site preparations

If possible, a wind screen on the lee side of a building should be used for shelter to minimize the wind effect on the balloon during inflation.

A ground cloth of some type is required to layout the balloon prior to filling. Sheets, plastic, rugs and tarpaulin have been used. The tarpaulin works as well as anything tried to date. Larger balloons usually come with a plastic sheet for this purpose.

2.3.4. Handling balloons

At the launch site, care must be exercised during actual manipulation of the balloon material to avoid damage. Material should be lifted into place, never grasped and pulled into place. Remove all jewelry, watches, and buckles. Also, cotton gloves or plastic gloves are recommended. Gloves of the type used in electical "claen room" environments work extremely well.

All payload equipment operations should be verified by a pre-approved checklist prior to inflation of the balloon.

The balloon construction train sequence is: balloon, parachute, payload(s). The parachute and payload is layed out on long tables connected prior to attachment of the balloon. The string is purchased from a kite store and has a tensile strength of 220 lbs. There are several knots required in the make up of a balloon train. This is a critical operation and some of the knots must be done just prior to flight. Knots have been secured using quick-setting glue and then wrapped using a good adhesive tape..

2.3.5. Handling helium

Helium must be handled carefully. It is not an explosive gas but is under high pressure up to 2300 PSI. This can be dangerous. When possible, bottles are kept in a truck bed. If they must be moved, they should be moved on a dolly and secured to the dolly and to a post or in some manner at the filling site. Install a gas regulator on the helium bottle to control fill pressure.

Gas transfer or inflation (for Kaysam type weather balloons) should begin only after all other preparations have been made. This is sometimes hard to accomplish but is the way the sequence should be planned. Helium is fed from the bottle through a hose to a PVC pipe that is put in the neck of the balloon about 4 inches. Clamp the balloon neck to the PVC pipe with a hose clamp. It is best to fill the balloon slowly, 15 to 20 minutes for a model 105G. A tare weight (we use pre-weighted sand bags) is attached to the balloon after it is upright. The balloon is filled until the tare weight is lifted off the ground. A very tight string tie is made around the neck of the balloon above the PVC. Then the PVC is removed and the end of the filling tube folded over and tied again and the whole joint taped with duct tape.

2.4. Launch Team

2.4.1. Launch Director

<<Jack Crabtree>> For each balloon flight there is a designated launch director. The launch director should be experienced in all facets of site preparation, preflight readiness, launch operations and, tracking and recovery of the balloon payload. The launch director is responsible for these activities including the safety of all personnel and property.

2.4.2. Balloon Lead

<<Merle McCaslin>> The balloon lead is responsible for having the balloon and support equipment at the launch site. This includes the helium, filling equipment, regulator, houses, ground cloth, tare weights, and miscellaneous items such as the tape, string, etc.

The balloon lead is also responsible for determining the tare weight and assuring the balloon is filled properly in a timely manner. He is also responsible for assuring the complete balloon train is secured and ready for flight.

2.4.3. Payload Lead

<<Mike Manes>> The Payload lead is usually the EOSS member who has served as prime contact for any new experiment which may be aboard the flight. He is responsible for ensuring that the experiment is properly prepared for flight, functional and communicating with the Shuttle. He is also responsible for ensuring that the Shuttle preflight checklist is complete and all functions verified.

2.4.4. Ground Station Lead

<<Rick von Glahn>> The Ground Station at EOSS flights is the control center during the flight. Ground station responsibilities include maintaining contact with and controlling the payload, and relaying information to the field chase teams concerning the status of the flight. The means by which this is accomplished varies from flight to flight depending on what capabilities the payload possesses. On the simplest flight with only a beacon we might not even set up a ground station. On the most complex of flights, we'll have computers receiving packet relayed data from the payload, ATV receivers and VCRs and TVs to monitor the live video as it's beamed down, a command radio used to send control codes up to the payload causing it to change transmit modes on some of the beacons, alter the angle of view on the video downlink and cut down commands to release the payload from the balloon and various other radios used to monitor the beacons, communicate with the field teams and run information nets.

2.4.5. Tracking and Recovery Lead

<<Greg Burnett>> The Tracking and Recovery Lead organizes the Tracking and Recovery Team. He tells the Launch Director about the availability of the Tracking Team to support the launch, and assigns the Field Coordinator for the chase. He conducts a net the evening prior to launch to give final instructions about the recovery process to include frequencies to be used, meeting times and locations of the tracking stations. It is during this net that stations planning to be a part of the Tracking and Recovery Team check in and receive a tactical call sign.

2.5. Launch commit criteria

2.5.1. Launch Checklist

A checklist of pre launch tasks and tests should be prepared beforehand and carefully checked as each activity is completed.

2.5.2. GO/NO-GO decisions

A preliminary GO/NO-GO decision is made prior to balloon inflation. Factors such as wind and weather conditions, completion of payload checkout, and road conditions for tracking and recovery will play a major part in this decision. This is an important decision because the expense of the helium �and probably the balloon� is committed at this point.

A final GO/NO-GO decision is made just prior to the launch itself. If conditions change or problems with balloon inflation or payload performance are experienced, a HOLD or NO-GO decision must be made.

2.5.3. Launch Team member roles

For each of these decisions all launch team members should be in mutual agreement and then abide by the decision of the launch director. A polling of the team members should precede each decision. Criteria and decision factors include the following:

  • The Balloon Lead shall indicate full readiness of balloon "train" which includes the balloon, parachute, cut-down devices, all wiring and cordage, attachments to payload and any auxiliary beacons.
  • The Payload Lead shall indicate full readiness of the payload package and auxiliary beacons, if any. A complete checkout of the payload on internal battery power for proper performance should precede the GO vote. Proper operation of any beacons should be verified. The Payload Lead should double check cord and wiring attachments including antennas as well.
  • The Ground Station Lead shall indicate full readiness of all ground station equipment and that proper command and telemetry capability is on-line. Any data or video recorders should be ready for activation by at least the final GO decision. Ground station antennas and cables shall not impair launch operations or personnel safety.
  • The Tracking and Recovery Lead indicates readiness of all remote tracking and recovery teams. While final deployment and positioning about the anticipated landing site may still be in process, the deployment should be on schedule and no factors adversely affecting personnel safety should be evident.

2.5.4. Weather

Weather conditions at the ground site and the anticipated recovery area should be suitable for launch. For smaller balloons, winds of up to 10 miles per hours can be tolerated but will complicate launch. For larger balloons, 10 miles per hour will probably be excessive. Winds immediately above the ground or launch level can greatly influence launch safety and performance. Before balloon inflation, one or two smaller pilot balloons can be tethered to measure winds as high as the extended balloon train will occupy during the launch sequence. Cloud cover criteria is generally 50 percent coverage or less, and no horizontal visibility impairment at any altitude below 60,000 feet of greater than 5 miles. Specific FAA waiver is required for any exception.

2.5.5. FAA requirements

All FAA requirements shall be met. All pre launch notifications must have been made and a concurrence for launch obtained, if required. Compliance with all balloon marking and lighting, cut down, and other FAA requirements shall be in effect. Any waivers shall be current.

Safety shall be paramount at all times.

2.5.6. Final launch decision

Only after consideration of all the above, shall the launch director issue the GO for launch. At this point, the launch should be carried out in a timely manner. If a significant time lapse is experienced due to changing conditions or problems, another evaluation and polling of the launch team should be made.

2.6. Launch sequence

The total balloon string should be stretched out with the balloon upwind of the payload so that the wind will carry the balloon in the direction of the payload. We use several people holding the balloon train. The payload is held by one or two persons and an additional person, stationed at the parachute, applies tension to the system by pulling on the parachute risers. The balloon is then released and rises, picking up the payload. If the wind is high the people with the bottom package may have to run with the payload to prevent the payload from dragging on the ground before it is picked up by the balloon. We have been releasing our balloons slowly, hand-over-hand on the string, but the above method is what is recommended and we plan to do it in this manner.

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