Pilotless drone aircraft are increasingly used for reconnaissance. All eyewitnesses testified that during the attack a pilotless drone hovered over the camp. These pilotless drones can search terrain and fire on targets. They produced a series of pilotless drones and airframes for the Apache helicopter. Three pilotless drones were shot down in succession. During this timeframe, the U.S. Air Force treated missiles as pilotless aircraft. Initially the laser designation was intended to be performed by the MQM-105 Aquila pilotless drone. BuAer's work on "pilotless aircraft," or drones, conflicted with BuOrd's development of guided missiles. A pilotless refueling rocket is sent to Icarus, but crashes. Obviously, to fly successfully, pilotless airplanes had to be dynamically stable. Ten pilotless UAV's would be produced in one year. While employed under the aegis of Graf Zeppelin, Flettner also developed pilotless aircraft projects. They say the aircraft will most likely be pilotless. The requirement for a pilotless target aircraft (PTA) arose in 1976. The department has been working with a small pilotless helicopter since 2008.