We took our prototype Swift3 to the High Alps of southern France for some extreme testing in a world class competition. Later that day they tried to knock down a second drone using wake turbulence from the F-16s, but that didn't work, the drone just kept flying.įly along with Brian Porter in the Swift 3 prototype as he races to 5th place overall in the Class 2 Hang Gliding World Championships! The drone came to rest in the desert mostly intact, but the fuselage was gutted and scorched. It wasn't easy for the jets flying at 250 kts to line up and score hits on the drone flying at 5000 ft and only 40 kts, but on the 9th attempt the fuel tank and batteries were hit and a fireball erupted. When they said they were going to shoot down one of my planes with a jet fighter, I thought "Good Luck!" I had no idea they were using a tracking pod that was able to lock on to my drone's heat signature while the F16's were still sitting on the runway. There were several bullet holes in the wings and tail, but nothing important was damaged until they put one right up the middle of the plane. It took 9 passes and one F-16 was out of ammo before a "magic bullet" brought the drone down. I built this model several years ago and have tested a dozen wing designs with it. This video shows one of my better efforts flying somewhat efficiently. Based on measured data, these wings are equal in efficiency to a well-designed small propeller, so there is still room for improvement!īack before the US Air Force and Russians were shooting/knocking down everything in the sky, the Air Force shot down one of my drones using F-16s armed with M61 Vulcan autocannons as part of a homeland security experiment. The wing design requires careful aeroelastic tuning and the drive mechanism must operate in resonance with the wings to create a nearly constant load at the drive motor. If any part of the system doesn’t fall within the narrow range of “goodness” the ornithopter will fly poorly or may not fly at all. There are many ways to build an ornithopter and the best approach remains unknown, as no man-made ornithopter has achieved the overall performance of medium to large sized birds. For man-made aircraft it remains simpler, lighter, and more efficient to use a propeller than flapping wings, but in nature flapping has been perfected. Ornithopter wings must propel and support the weight of the aircraft while dynamically deforming to perform efficiently. Why build an ornithopter? Because the challenge of understanding and duplicating efficient flapping flight is difficult and therefore an excellent test of engineering skills. This model is a smaller, much simpler version of my original demonstrator. This idea is not new, it was first proposed in the 1940’s, and I flew an unstable tailless demonstrator 36 years ago to test the idea. The active control system is based on modified dRehmFlight open-source software and is explained at the end of the video. Placing the CG behind the neutral point allows this design to trim with nearly optimal flap deflection for low drag at each lift coefficient, whereas the inherently stable design trims with flap deflection that produces increased drag and reduced maximum lift. The video shows the model flying with computer stabilization and with the feedback control turned off which results in immediate pitch divergence. Here is a video of an inherently pitch-unstable tailless design that I built to investigate the interaction between aerodynamic performance and relaxed pitch stability in tailless aircraft. It’s best to watch this full -screen or you might miss some of the details.
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