WASHINGTON — The U.S. Defense Department is one step closer to having swarming drones that it can launch from military planes and recover in midair, having successfully conducted the first flight of the Gremlins aircraft in November.
The test, which occurred at Dugway Proving Ground, Utah, proved that a C-130A could successfully launch an X-61A Gremlins Air Vehicle, said Tim Keeter, who manages the program for Dynetics. The company won the Gremlins contract from the Defense Advanced Research Projects Agency in 2018.
“It gives us a lot of confidence going forward that this vehicle can fly where it’s supposed to fly, how it’s supposed to fly,” Keeter said during a Jan. 21 phone call with reporters. “Now the team can be principally focused on the other portion of our program plan … which is to successfully rendezvous with a C-130, dock with our docking system … and safely recover the vehicle.”
During the test, which lasted 1 hour and 41 minutes, the X-61A flew with no anomalies and the DARPA-Dynetics team completed all test objectives, including transitioning the X-61A from a cold-engine start to stable flight; validating the Gremlins’ data links and handing off control of the drone between air and ground control stations; deploying the docking arm; and collecting data on the air vehicle.
However, during the recovery process, the drone crashed to the ground and was destroyed. The drogue parachute, which deployed first to slow the air vehicle, functioned as planned, Keeter explained. However, the larger main parachute — which would soften the landing of the air vehicle so that the drone could be reused — did not correctly deploy due to a mechanical issue.
Dynetics has built four other Gremlins vehicles, leaving enough drones to accomplish the program’s primary requirement to fly and recover four Gremlins in 30 minutes, said Scott Wierzbanowski, DARPA’s Gremlins program manager.
The next demonstration, set for sometime this spring, will verify whether the Gremlins can be successfully recovered by the C-130 while in flight. Wierzbanowski characterized this test as critical for proving that the Gremlins can be reused over multiple missions — a key point for bearing out the cost-effectiveness of the concept.
"If I have an expendable vehicle, at some point I'm not going to want to be able to use those things because they’re just too expensive,” he said. “But if I can recover them and then amortize the cost of that vehicle over 10 or 20 or 30 sorties, maybe there's a bend in the curve somewhere that really will allow us to benefit from these smaller, more affordable, attritable systems."
During the recovery process, the C-130 will lower a towed capture device that will mate with the Gremlins drone, thus avoiding the turbulence generated by the wake of the larger aircraft, Keeter said. Once the drone is stabilized by the capture device, an engagement arm deploys, docking with the X-61A and bringing it inside the C-130 cargo bay to be stowed.