As recently as the year 2000, remotely piloted aircraft (RPA) were an obscure niche within the US Air Force (USAF). Today, the USAF trains more RPA pilots than fighter and bomber pilots combined. With only one entirely new manned tactical airplane under development by the USAF (the F-35A) at present, the focus of new USAF combat aircraft development has strongly shifted to RPAs. It would seem that USAF RPAs suddenly appeared ex nihilo, but actually the history of USAF RPAs starts with World War II-era radio-controlled target drones. By the 1950s, unmanned research vehicles in the X-plane series were in use. The 1960s and early 1970s saw the intensive use of reconnaissance drones over North Vietnam and China. After the Vietnam War ended, there were predictions that the USAF would continue to build its RPA force, but by the late 1970s there were no operational RPAs remaining in the USAF inventory and there would be none for the next two decades. Yet in hindsight, during this period of inactivity the seeds were planted for the USAF RPAs of today and the future.
Some of the RPAs that will be described are:
• OQ-2 - The first operational radio-controlled target drone used by the US Army.
• X-7 - Early ramjet testbed and the fastest aircraft in the world until the famous X-15 research aircraft.|
• X-10 - First turbojet-powered aircraft to exceed Mach 2.
• QF-80 and QB-17 - Conversions of manned aircraft that were used for sampling of atmospheric nuclear tests and as targets for early guided missile flight tests.
• Q-4 - Supersonic target drone that faded into obscurity but provided the parachute technology used for the Apollo command module.
• AQM-34 - First RPA used for operational reconnaissance missions.
• D-21 - The unmanned member of the famous Lockheed Blackbird family.
• Scathe Mean - The classified program to use BQM-74C aerial targets as decoys during Operation Desert Storm.
This paper does not cover flight test in the manner of a typical SFTE symposium paper, although references to RPA flight test and flight research using RPAs will abound. However it closely fits the theme of "Evolution of Flight Testing from Manned Vehicles to UAVs" and will provide a historical context for other presentations at the symposium. The paper is based on research for a two-volume set of books on the subject that is currently in work.