NASA’s Armstrong Flight Research Center took another step toward developing a novel rocket-launching technique called the Towed Glider Air-Launch System (TGALS) by fit-checking a subscale twin-hulled glider with its experimental rocket payload. This was the first time the two vehicles had been mated using actual flight hardware.
Project advocates hope an operational system based on the TGALS might significantly reduce the cost and improve the efficiency of sending small satellites into space.
According to project manager Gerald Budd, the ultimate goal is to build a relatively inexpensive remotely or optionally piloted glider that will be towed aloft by a large transport aircraft. Following release at around 40,000 feet, the glider will launch a booster rocket into an optimal trajectory to place its payload into low Earth orbit.
Armstrong’s TGALS project is a proof-of-concept demonstration using radio-controlled one-third scale models of both glider and rocket. NASA researchers constructed a 27-foot- wingspan, twin-hulled glider in Armstrong’s Small Unmanned Aircraft Systems Research Lab – the model shop – and expect to fly it later this year, towed aloft by one of the center’s small DROID – for Dryden Remotely Operated Integrated Drone – unmanned aircraft. The sailplane will eventually carry the scale-model Mini Sprite rocket, designed and built by Whittinghill Aerospace of Camarillo, California, under the Small Business Innovation Research (SBIR) program.
In January, the DROID towed a single-hulled sailplane model aloft from the north end of Rogers Dry Lake at Edwards Air Force Base, Calif., to validate TGALS demonstration systems and procedures. Flight objectives included validation of towing techniques, tests of the tow release system and autopilot, transition from manual to autonomous flight, and demonstration of the remote pilot’s ability to fly the glider from a ground-based cockpit using visual input from a miniature video camera on board the aircraft.
Researchers will use the results of those tests and lessons learned during the next phase of the project, which involves tow tests of the twin-fuselage sailplane model that is representative of the proposed TGALS configuration.
Initial research and development is being internally funded through NASA Armstrong’s Center Innovation Fund. Potential Department of Defense and industry partnerships are also being explored.