Robot pilots prove adept at refuelling tasks

Published 20 August 2007

Mid-air refueling is tricky, but DARPA has been testing robots that perform the mission impressively

The Pentagon’s DARPA (Defense Advanced Research Projects Agency) is trying to encourage the development of droid pilots. In a program dubbed AARD (Autonomous Airborne Refueling Demonstration), an F-18 fighter jet was given a digital overhaul by NASA to see if it could complete the demanding task of air-to-air refueling with no human intervention whatsoever. For reasons of safety, there was a qualified pilot along for the ride, ready to take the controls if anything were to go astray, but the droid pilots actually score higher when compared to their human predecessors. With eleven of these mid-air refueling tests conducted over the last year, the droid pilot was able successfully to jack into the fuel pipe trailing behind the air tanker. The robot flyer was able to lock in and attach to the fuel nozzle, even in high turbulence conditions that had the port flapping up and down by five feet or more. The bots were also able to plug-in while banking (turning), a very trickery maneuver for even to best of human fly boys. “Although pilots routinely follow a tanker through turns while connected, they typically do not attempt to make contact in a turn,” says DARPA. NASA says that the software used to control the robots underwent a number of revisions and improvements. NASA’s test pilot Dick Ewers says that last year the robot flew “like a second lieutenant,” but with subsequent upgrades, the robot rookie was upgraded, and now it is “better than a skilled pilot.”

There are many advantages to the robotic pilots, chief among them is that they do not leave the military to work flying a 747, forcing the air force to recruit and train another pilot all over again. DARPA had added how the robotic pilot had by the “algorithms were actually able to precisely match the drogue motion — something pilots are specifically taught to avoid… the system followed the drogue through a full three-foot cycle in the two seconds before making contact, never deviating more than four inches from the exact centerline of the drogue, all the while traveling at 250mph, 18,000 feet above the Tehachapi Mountains.” Human pilots, on the other hand, try to slot into the fuel port with a forward move at the precisely right moment. Pilots, being the most colorful bunch, have traditionally described the maneuver as “like taking a running [expletive deleted] at a rolling doughnut.”