The Ryan Firebee was a series of target drones or unmanned aerial vehicles developed by the Ryan Aeronautical Company beginning in 1951. It was one of the first jet-propelled drones, and one of the most widely-used target drones ever built. In 1959, Ryan Aeronautical performed a study to investigate how the company’s Firebee target drone could be used for long-range reconnaissance missions. Ryan engineers concluded they could increase the Firebee’s range to allow it to fly south over the Soviet Union after launch from the Barents Sea, with recovery in Turkey.
The Firebee has a low radar cross section, making it hard to detect. With lengthened wings, the drone would also be able to fly at high altitude, further increasing its elusiveness. It could be launched by a Lockheed DC-130 Hercules, or RATO-boosted from a land site or ship.
The 147Ds combined the functions of reconnaissance and the original Firebee mission of aerial target. They were to be used as bait for SA-2 SAMs to obtain data on signals associated with the SA-2. The SAM was targeted by a radar codenamed Fan Song and it was simple enough to pick up its signals with a normal SIGINT aircraft. However, the SA-2 was radio-controlled to the target by a ground command link, with the missile carrying a transponder that sent back a signal to the Fan Song radar to allow tracking. Picking up these signals was hazardous, since they only came on when a missile was launched. The proximity fuze signal was the most dangerous, because it would only be detected moments before the SAM detonated.
A special “SAM sniffer” payload was installed on the Fire Fly to pick up these signals, with the drone relaying the data to an ERB-47 electronics warfare aircraft. An active radar enhancement device was installed to encourage the enemy to take shots at the drone. The three Model 147Ds were delivered in December 1962. The Fire Fly code name had leaked in the meantime, so the new drones were given the codename Lightning Bug.
In July 1963, the Lightning Bugs reached full operational status, though they had yet to fly an operational mission. In late December 1963, the Air Force ordered fourteen more Model 147Bs. By this time, Fidel Castro was threatening to shoot down U-2s flying over Cuba, and in May 1964 a study concluded that the Lightning Bug was the best alternative. However, after information about the proposal leaked to the press, the administration decided to back up the U-2s with the Lockheed A-12, an early version of the SR-71 Blackbird spyplane.
