June 17, 1998
The group is the Huntsville Alabama L5 Society (HAL5), a chapter of the grassroots National Space Society (NSS). The rocket will be launched from a high altitude balloon - a concept called a "rockoon". For this reason, HAL5 named its project High Altitude Lift-Off (HALO).
For safety reasons, the balloon will be launched from a barge (provided by NASA) out in the Gulf of Mexico, about 60 miles southeast of New Orleans. June winds will carry the balloon about 30 miles southwest as it rises to 100,000 feet. The command to launch the rocket will be sent only once the balloon is safely over open ocean and the rocket is pointed away from land.
The balloon gondola will carry an amateur television (ATV) camera to record the launch live and transmit the color video back to earth. The frequency is 434.00 MHz, which corresponds to Cable Ready TV channel 59. The rocket also will carry an ATV camera, a higher-resolution color model. The frequency is 1255 MHz. The rocket will also being transmitting telemetry data via APRS packet radio on a FM frequency of 441.050 MHz. For more details, please see the Web site.
Altitude verification for the rocket will be primarily based on signals from an onboard Trimble GPS receiver. Backup will come from accelerometer data, and then from the video camera, which is oriented so that the curvature of the Earth can be viewed, recorded, and later measured to estimate the altitude.
The balloon launch is scheduled for 7 AM CDT, to obtain calm winds and to satisfy FAA requirements. Rocket launch will occur about 2-1/2 hours after the balloon launch (about 9:30 AM CDT). If Saturday is windy or rainy, the launch will be postponed until Sunday, or three weeks later on Saturday, July 11.
Because the balloon will be launched from a barge with very limited passenger capacity, members of the Press and other visitors should go to the Press Site to be setup at the Sea Lab on the east coast of Dauphin Island, 40 miles south of Mobile, Alabama. The NASA barge will leave Michoud, La., on Friday morning, providing plenty of time for reporters who wish to observe the departure to reach the Dauphin Island site before the Saturday morning balloon launch.
If the recovery boat has room, some members of the Press will be allowed onboard. It is hoped that the boat will be fast enough to observe the balloon launch from the barge, then track the balloon to the recovery point.
For more details (including directions, hotels, restrictions, and requirements), please see the HALO Web site.
Via Project HALO, HAL5 is bringing up to modern standards a launch vehicle concept called a "rockoon". A rockoon is a rocket that is launched from a high altitude balloon. The rockoon approach allows a small rocket to obtain a very high altitude because there is little air to slow it down during launch. Rockoons were first flown by James Van Allen in the 1950's as part of a joint Navy/university project, but were abandoned when sufficiently large ground-based sounding rockets became available.
HAL5 made amateur rocketry history last year (May 11, 1997) when it successfully performed the first amateur rockoon mission from a high altitude, and made professional rocketry history by launching the first hybrid rocket from a high altitude. For more details on the historic Sky Launch 1 rockoon mission, please see this HALO Web site.
Since 1994, HAL5 has updated the rockoon concept using modern amateur rocketry and electronics technology, added to today's now-affordable composite materials and high altitude balloon technologies. HAL5's goal is to make space more affordable for students, amateurs, experimenters, and researchers.
In 1996, the NASA Marshall Space Flight Center (MSFC) expressed to HAL5 its interest in the rockoon approach. In an effort to find new ways to reduce the cost of rocket launches, NASA is examining alternate launch sites and methods. HAL5 and NASA MSFC signed a Cooperative Agreement in October 1996 for the Sky Launch 2 (SL-2) rockoon mission. For SL-2, HAL5 is providing the amateur rocket, high altitude balloon, launch support hardware, tracking equipment, and recovery boat.
NASA MSFC and the NASA Michoud Assembly Facility are providing an oceangoing barge to serve as the balloon launch platform, plus helium for the balloon, nitrous-oxide for the rocket, and some money towards the reimbursement of materials purchases. HAL5 is raising the rest of its money via its Donation Program.
The HALO SL-2 rocket utilizes hybrid propulsion, whereby an inert solid fuel is kept safely away from a liquid oxidizer until the rocket is ignited. The solid fuel used for the HALO rocket is pure asphalt, the same material used on streets and roofs. The liquid oxidizer used for the rocket is nitrous-oxide, the same "laughing gas" used by dentists. This simple fuel combination is 85% as effective as the best aerospace industry solid rocket propellants (250 vs. 300 vacuum specific impulse).
After constructing a small rocket motor test facility in early 1995, HAL5 performed over 60 static firings of its hybrid rocket motors. In 1996, HAL5 launched its first hybrid rocket from the ground, and then in 1997, launched the first hybrid rocket from a high altitude.
The home-built HALO SL-2 hybrid rocket, to be launched from a balloon over the Gulf of Mexico, will become the first of its kind to ever make it into space - if it successfully exceeds an altitude of 50 nautical miles (300,000 feet). The official record for highest altitude achieved by a hybrid rocket is held by a NASA-industry team who, on Jan. 8, 1997, sent a nitrous-oxide and HTPB-rubber hybrid sounding rocket from the ground to 20 nautical miles. Unofficially, HAL5 has estimated that its HALO hybrid SL-1 rocket, launched May 11, 1997, reached an altitude between 30 and 36 nautical miles. The HALO team has worked very hard during the past year to ensure that the new HALO SL-2 rocket will send back data and video throughout its balloon ascent, rocket trajectory, and landing by parachute.
The high-altitude helium balloon to be used, purchased from Raven Industries, is made of clear polyethylene plastic over 120 feet long, but thinner than a sandwich bag (only 0.35 mils thick). At the launch altitude of 100,000 feet, the balloon, which has a volumetric capacity of 245,000 cubic-feet, will expand to 78 feet in diameter. Floating in the frigid thin upper atmosphere, the balloon will be brittle enough to "pop" when the HALO SL-2 rocket safely shoots through it.
For more information on the entire HALO program, please see the main Project HALO Web site.
At a glance