Release No. 98-26

NASA LOOKS TO FUTURE SCIENCE EXPLORATION USING ULTRA-LONG DURATION BALLOON

NASA has begun preparation of a new unpiloted scientific balloon that will fly around the world in the year 2000. The new super pressure Ultra-Long Duration Balloon (ULDB) is designed to stay afloat at altitudes reaching 120,000 feet for up to 100 days with over a ton of scientific and support equipment. This new technology presents significant opportunities to perform many types of research in space and earth science effectively and inexpensively.

NASA Goddard Space Flight Center's Wallops Flight Facility, Wallops Island, Va., announced this week that Raven Industries, Sioux Falls, S.D. has been selected to manufacture the new super pressure Ultra-Long Duration Balloon. 

Raven Industries is to fabricate the ULDB Demonstration 2000 balloon as well as all test flight and backup balloons leading up to the first demonstration flight of the balloon currently scheduled for December 2000 from New Zealand. Each balloon is estimated to cost approximately $360,000.

"The selection of Raven Industries to manufacture the ULDB marks the end of months of testing on different material composites. We can now proceed with the design phase and prepare for the first test flight of the balloon using the new technology, which is scheduled for March 1999 from Ft. Sumner, N.M.," said Steve Smith, NASA Wallops Project Manager for the ULDB.

NASA presently flies conventional and long duration scientific zero pressure balloons with flights lasting from a day to three weeks. Zero pressure balloons are made of a thin polyethylene material, (0.8 millimeters), about the same thickness as ordinary sandwich wrap. They are partially inflated with helium when launched. As they rise, helium expands until the balloon reaches full inflation. Fully inflated these scientific balloons range up to 40 million cubic feet in volume, 600 feet in diameter and are taller than a 60-story building. 

Zero pressure balloons must vent some gas as daytime temperatures rise causing the balloon to expand. As night approaches, the remaining gas shrinks causing the balloon volume to decrease and the balloon to descend. In order to stay aloft, the balloon system must drop ballast. As a result, most zero-pressure balloon flights last only a short time.

"Similar in size to current balloons, the super pressure balloon will maintain lift, size and shape and will not lose significant altitude due to atmospheric influences. The material composite developed by Wallops will make this possible," said Harvey Needleman, Chief, Balloon Program Office, NASA Wallops Flight Facility, Wallops Island, Va. "The current prototype is a high strength, low weight composite material composed of polyester fabric, polyester film, and polyethylene film. The new material will be capable of withstanding high internal pressures caused by solar heating." 

"For missions not requiring an orbital or deep space placement, you can create larger, more sophisticated payloads at significantly lower cost," said Dr. Jack Tueller, Balloon Project Scientist at NASA's Goddard Space Flight Center, Greenbelt, MD. Tueller said that balloon launched payloads are ideal for high resolution optical and infrared telescopes to search for planets around nearby stars, hard x-ray and gamma-ray telescopes to study black holes, and cosmic microwave background surveys to study cosmology and the early universe.

More information about the NASA's Balloon Program can be found at: http://www.wff.nasa.gov/scientific/balloons.html