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Air Force Explores Balloon-Assisted Launches
By STEW MAGNUSEN
Space News Correspondent
posted: 10:56 am ET, 21 January 2003
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PAPILLON, Neb. — The U.S. Air Force is looking for novel ways to loft small satellites cheaply and on short notice, and a small group of space enthusiasts who began their business in a garage hope to help the service do that with a rocket that would launch from a platform carried aloft by balloons.
"If an adversary were to take out our systems, and we need to get a small satellite up there [quickly], we need to explore ways to do that," said Maj. Robert Blackington, demonstration officer at the Space Warfare Center’s Air Force Space Battlelab, Shriever, Air Force Base, Colorado Springs, Colo.
"Adversaries are getting smarter and we have to stay one step ahead of them," Blackington said in a phone interview.
JP Aerospace, a small start-up with four employees and about 40 volunteers based in Rancho Cordova, Calif., is the contractor for the balloon launch concept, which could fly in 2005 if the Air Force funds the demonstration in its 2004 budget, Blackington said.
The battlelab is seeking a total of $760,000 in 2004 and 2005 to see the test launch through, Blackington said. The battlelab is restricted to demonstrations that cost under $1 million and take place within 18 months of initial receipt of funding, he said.
The JP Aerospace concept would use balloons to carry a platform 30,300 meters into the atmosphere and then launch a two-stage rocket with a payload weighing up to 20 kilograms to low Earth orbit. Plans for the demonstration flight call for the rocket to loft an 8-10 kilogram satellite, which would make roughly two orbits before re-entering the atmosphere and burning up, according to John Powell, president of JP Aerospace.
Powell began working on the balloon-launch concept in 1993, when, operating out of his garage in Davis, Calf., he set out to create the first amateur organization to deliver a payload to space. It wasn’t just a lark. In the late 1970s, at the age of 17, he and some friends had already begun competing for NASA satellite contracts.
With only three years of college under his belt, he moonlighted as a computer programmer to support the business. Powell said he refocused his attention to building an inexpensive launch system when he determined that that was a bigger challenge and represented the greater need in the industry.
Powell turned to the work of space science pioneer James Van Allen, who developed the concept of balloon-assisted launches at the University of Iowa in the 1950s. Van Allen, discoverer of the Van Allen Radiation Belt, used a rockoon to explore cosmic ray intensity, auroral particles and the Arctic magnetic fields. The rockoon system carried rockets via balloon to heights of 1,500 meters, and from there they were launched to altitudes of up to 75,700 meters.
JP Aerospace’s rocket will launch from a platform carried aloft by Mylar balloons attached to five radial arms. The rocket will launch vertically from the center of the platform, which would then make a controlled descent via parachute for ground retrieval.
The platform essentially would serve as a low-cost, reusable first stage, making balloon-assisted launches cheaper than ground-launched rockets, Powell said.
The rocket, developed in-house, is designed to fire in the rarified air of the upper atmosphere, Powell said. Because the rocket does not have to travel at high speed through the lower atmosphere, where wind resistance is relatively stiff, its airframe can be considerably lighter than those of ground-launched rockets, he added.
"That’s where you get the real benefit of balloon-launched rockets," Powell said. "It’s not the fact that you’re really high, although that helps a little bit — it’s that you’re firing in a vacuum, so your airframe only has to weigh a few" kilograms, he said.
The JP Aerospace platform has been tested at altitudes of up to 40,000 meters, Powell said. The rocket has been launched from the platform at altitudes as high as 10,000 meters and reached heights of roughly 22,000 meters, he said.
Funding for the tests to date was provided by sponsors who have placed their corporate logos on the platform, Powell said. Along with the rocket and payload, the platform carries up to 17 computers as well as video cameras for live feeds to the ground. "It’s like a whole miniature launch complex sitting up there," Powell said.
JP Aerospace is pursuing commercial opportunities for its system, and toward that end has teamed with Stanford University’s Cubesat program. The Cubesat is a microsatellite platform used by Stanford for a variety of experiments in areas like remote sensing and communications, Powell said. A Cubesat is expected to be the payload for the balloon launch demonstration, but the university has not settled on the application for the microsatellite, he said.
The Air Force initially was attracted to the balloon-assisted launch concept because finding piggyback rides for small satellites on the large rockets that conduct the vast majority of U.S. missions takes too long, Blackington said.
"If you want to get a 10- to 15-kilogram payload into space you have to get in line," Blackington said. The process can take three to five years, he added.
Adam Chu, chief project scientist at the battlelab for El Segundo, Calif.-based Aerospace Corp., said miniaturization of electronics in recent years makes small satellites more useful.
Small satellites have the capability to provide services ranging from imagery collection to communications or navigation, Chu said. If a military satellite system were to be knocked out by an adversary, the Air Force might have to deploy an interim capability requiring perhaps several launches in a single day, Blackington said.
"We want to launch eight to nine a day if we had to and replenish that supply on short notice," Blackington said.
Balloon-assisted launch is one of at least three novel concepts that the Pentagon is looking at for launching small payloads affordably. One uses a gas gun technology that dates back to World War 1 to accelerate a projectile as it travels along the barrel, Blackington said. The Defense Advanced Research Projects Agency is looking at ways to launch small satellites from modified jet fighter aircraft, Blackington said.
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