In many countries, the bureaucratic overhead required for high altitude balloon launches is minimal when the payload is below a certain weight threshold, typically on the order of a few kilograms. This makes the process of launching these small HABs accessible to many students and amateur groups. Despite their smaller size, these HABs still often ascend to (and past) altitudes on the order of , providing easy stratospheric access for scientific and educational purposes. These amateur balloon flights are often informed in their operations by the use of a path predictor. Before launch,
weather forecasts containing predicted wind vectors are used to numerically propagate a simulated HAB along a trajectory, predicting where the actual balloon will travel.
Legality in the United States In the United States, high-altitude ballooning is governed by
Title 14 Part 101 in the
Code of Federal Regulations; balloons are only subject to regulation if their payload package weighs more than four pounds and has a larger density than three ounces per square inch, if the payload package is larger than six pounds regardless of density, or if the payload is connected to a balloon by a rope requiring more than 50lb of force to break it. Any balloons meeting these requirements are subject to regulation, usually involving coordination with the local
air traffic control facility, implementation two emergency payload cut-down systems and two emergency balloon terminating systems.
Amateur radio high-altitude ballooning Testing radio range is often a large component of these hobbies.
Amateur radio is often used with packet radio to communicate with 1200
baud, using a system called
Automatic Packet Reporting System back to the ground station. Smaller packages called
micro or
pico trackers are also built and run under smaller balloons. These smaller trackers have used
Morse code,
Field Hell, and
RTTY to transmit their locations and other data. The first recorded amateur radio high-altitude balloon launches took place in Finland by the Ilmari program on May 28, 1967, and in Germany in 1964.
ARHAB program Amateur radio high-altitude ballooning (
ARHAB) is the application of analog and digital
amateur radio to
weather balloons and was the name suggested by Ralph Wallio (amateur radio callsign W0RPK) for this hobby. Often referred to as "The Poor Man's Space Program", ARHAB allows amateurs to design functioning models of spacecraft and launch them into a space-like environment. Bill Brown (amateur radio callsign WB8ELK) is considered to have begun the modern ARHAB movement with his first launch of a balloon carrying an amateur radio transmitter on 15 August 1987. An ARHAB flight consists of a balloon, a recovery parachute, and a payload of one or more packages. The payload normally contains an amateur radio transmitter that permits tracking of the flight to its landing for recovery. Most flights use an
Automatic Packet Reporting System (APRS) tracker which gets its position from a
Global Positioning System (GPS) receiver and converts it to a digital radio transmission. Other flights may use an analog beacon and are tracked using
radio direction finding techniques. Long duration flights frequently must use
high frequency custom-built transmitters and slow data protocols such as
radioteletype (RTTY),
Hellschreiber,
Morse code, and
PSK31, to transmit data over great distances using little battery power. The use of amateur radio transmitters on an ARHAB flight requires an amateur radio license, but non-amateur radio transmitters are possible to use without a license. In addition to the tracking equipment, other payload components may include sensors, data loggers, cameras,
amateur television (ATV) transmitters or other scientific instruments. Some ARHAB flights carry a simplified payload package called
BalloonSat. A typical ARHAB flight uses a standard latex weather balloon, lasts around 2–3 hours, and reaches in altitude. Experiments with
zero-pressure balloons,
superpressure balloons, and valved latex balloons have extended flight times to more than 24 hours. A zero-pressure flight by the
Spirit of Knoxville Balloon Program in March 2008 lasted over 40 hours and landed off the coast of Ireland, over from its launch point. On December 11, 2011, the California Near Space Project flight number CNSP-11 with the call sign K6RPT-11 launched a record-breaking flight traveling from
San Jose, California, to a splashdown in the
Mediterranean Sea. The flight lasted 57 hours and 2 minutes. It became the first successful U.S. transcontinental and the first successful transatlantic amateur radio high-altitude balloon. Since that time, a number of flights have circumnavigated the Earth using superpressure plastic film balloons. Each year in the United States, the Great Plains Super Launch (GPSL) hosts a large gathering of ARHAB groups.
BEAR program Balloon Experiments with Amateur Radio (BEAR) is a series of Canadian-based high-altitude balloon experiments by a group of Amateur Radio operators and experimenters from Sherwood Park and Edmonton, Alberta. The experiments started in the year 2000 and continued with BEAR-9 in 2012, reaching . The
balloons are made of
latex filled with either
helium or
hydrogen. All of the BEAR payloads carry a tracking system comprising a
GPS receiver, an
APRS encoder, and a radio transmitter module. Other experimental payload modules include an
Amateur Radio crossband repeater, and a
digital camera, all of which is contained within an insulated foam box suspended below the balloon.
BalloonSat A BalloonSat is a simple package designed to carry lightweight experiments into near space. They are a popular introduction to engineering principles in some high school and college courses. BalloonSats are carried as secondary payloads on ARHAB flights. One reason BalloonSats are simple is that they do not require the inclusion of tracking equipment; as secondary payloads, they already are being carried by tracking capsules.
Space Grant started the BalloonSat program in August 2000. It was created as a hands-on way to introduce new science and engineering students interested in space studies to some fundamental engineering techniques, team working skills and the basics of space and Earth science. The BalloonSat program is part of a course taught by Space Grant at the University of Colorado at Boulder. Often the design of a BalloonSat is under weight and volume constraints. This encourages good engineering practices, introduces a challenge, and allows for the inclusion of many BalloonSats on an
ARHAB flight. The airframe material is usually
Styrofoam or Foamcore, as they are lightweight, easy to machine, and provide reasonably good insulation. Most carry sensors, data loggers and small cameras operated by timer circuits. Popular sensors include air temperature, relative humidity, tilt, and acceleration. Experiments carried inside BalloonSats have included such things as captive insects and food items. Before launch, most BalloonSats are required to undergo testing. These tests are designed to ensure the BalloonSat will function properly and return science results. The tests include a cold soak, drop test, function test, and weighing. The cold soak test simulates the intense cold temperatures the BalloonSat will experience during its mission. A launch and landing can be traumatic, therefore the drop test requires the BalloonSat to hold together and still function after an abrupt drop. The function test verifies the BalloonSat crew can prepare the BalloonSat at the launch site.
Variety payloads Besides conducting scientific activities, schools, influencers and other individuals have launched a wide variety of novelty payloads to the stratosphere with high-altitude balloons. These have included teddy bears,
LEGO figurines, hamburgers,
Cornish pasties,
garlic bread, bacon and cans of beer. Japanese electronics manufacturer
Toshiba attempted to record an advertisement in near space with an armchair and cameras tethered to a high-altitude balloon. ==Geostationary balloon satellite==