Spurred by the 1960 U-2 incident, the United States Air Force gained a renewed interest in using unmanned aerial vehicles (UAV), or drones, to obtain intelligence on the SA-2 Guideline surface-to-air missile system.Under the code names "Lightning Bug" and "Compass Cookie", Firebee target drones were modified for reconnaissance as the Ryan Model 147.While perfect for reconnaissance, the use of a ground-based radar van for command, track and control limit the combat ability of drones.The 100 SRW was then re-designated as the 100th Air Refueling Wing (100 ARW) and relocated to Beale AFB, operating KC-135 Stratotanker aircraft, until its later reassignment to its current home of RAF Mildenhall, United Kingdom.Instruments displayed all data transmitted from the drone—such as heading, speed, altitude, power setting and flight attitudes.Navigation and tracking data were fed to a system that plotted the current position of both the drone and DC-130 on a large map board in front of the operators.They were equipped with an analogue computer which controlled speed, altitude, heading, engine settings, sensors and recovery systems.These could be fixed, turreted, or scanning horizon-to-horizon film cameras; some provided fine detail of specific targets while others covered large areas.The on-board recovery system consisted of a servomechanism that shut down the engine, deployed a drag chute (to cause the drone to nose over) and opened the main parachute at a preset altitude.On ground impact a sensor operated a charge that severed the chute risers allowing the drone to be recovered.