Hawks and eagles glide on currents of rising warm air called thermals to extend their flight time without needing more fuel. NASA aerospace engineer Michael Allen and a team of engineers working on the Autonomous Soaring Project at Dryden Flight Research Center have succeeded in extending the range of small unmanned air vehicles (UAVs) by programming them to autonomously soar on thermals.
During the test, the software programmed into the 15-pound motor-glider's autopilot flew the aircraft on a pre-determined racetrack over the northern portion of Rogers Dry Lake at Edwards Air Force Base until it detected an updraft. Once the aircraft started to rise on the current, the engine automatically shut off and the aircraft circled to stay within the convective lift resulting from the thermal or updraft.
Did it work? According to the researchers, the small UAV added 60 minutes to its endurance by soaring autonomously. Nicknamed Cloud Swift after a bird known for feeding on insects found in rising air masses, the modified model sailplane gained an average altitude in 23 updrafts of 565 feet, and in one strong thermal ascended 2,770 feet.
Science fiction writers have been using UAVs for surveillance for a generation or more. In his excellent 1980 science/fantasy novel Changeling, Roger Zelazny describes small, autonomous surveillance craft called 'tracer-birds' that were also able to detect and ride air currents:
Take a look at an extremely cool, lightweight bird-like UAV in Robotic Bird Has USAF Flocking. Read more about NASA research on extending UAV endurance. Thanks to Tariq Malik for contributing the story tip.
(This Science Fiction in the News story used with permission from Technovelgy.com - where science meets fiction.)