The Ryan Model 147 Lightning Bug is a jet-powered drone, or unmanned aerial vehicle, produced and developed by Ryan Aeronautical from the earlier Ryan Firebee target drone series.
Beginning in 1962, the Model 147 was introduced as a reconnaissance RPV (Remotely Piloted Vehicle, nomenclature of that era) for a United States Air Force project named Fire Fly. Over the next decade – assisted with secret funding from the recently formed National Reconnaissance Office along with support of the Strategic Air Command and Ryan Aeronautical's own resources – the basic Model 147 design would be developed into a diverse series of variants configured for a wide array of mission-specific roles, with multiple new systems, sensors and payloads used, modified and improved upon during the operational deployment of these drones in Southeast Asia. Missions performed by the Model 147 series RPVs included high- and low-altitude photographic and electronic aerial reconnaissance, surveillance, decoy, electronic warfare, signals intelligence, and psychological warfare.
The Ryan drones were designed without landing gear for simplicity and to save weight. Like its Firebee predecessor, the Model 147 could either be air-launched from a larger carrier aircraft or launched from the ground using a solid rocket booster; at completion of its mission the drone deployed its own recovery parachute which could be snatched in mid-air by a recovery helicopter (in a combat environment it was naturally not desired to recover the drone on, from or near enemy territory and ground or water impact could also cause damage to or loss of the drone or its payload).
At the end of the Vietnam War in 1975 the U.S. military's available funding and need for combat drones severely declined, even as Teledyne Ryan introduced further advanced developments of the Model 147 series such as the BGM-34 strike and defense suppression RPVs. Costs of maintaining the Lightning Bugs at full readiness could no longer be justified. Only by the 1990s did substantial interest, organization and funding again emerge from the U.S. Air Force and intelligence agencies to develop, acquire and widely deploy combat UAVs.
Development
Ryan Model 136 Red Wagon and Lucy Lee
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, or JATO-boosted from a land site or ship.
Ryan presented its report on the studies to the U.S. Air Force in mid-April 1960. On 1 May 1960 an American Lockheed U-2 spy plane was shot down over the USSR and its pilot, Francis Gary Powers, captured. On 1 July a Boeing RB-47H reconnaissance aircraft flying an electronic intelligence mission in international airspace near the Soviet border was shot down; four of its crew were killed and the other two captured. A few days later, the Air Force awarded Ryan a US$200,000 contract to perform further studies.
Ryan conducted radar measurements on sub-scale Firebee models and determined that their radar signature could be reduced by placing a wire screen over the jet intake, painting parts of the drone with non-conductive paint, and placing radar-absorbent material pads on both sides of the fuselage. Test flights of the modified Firebees were performed in September and October 1961. Flights were given a cover story, describing the drones as high-altitude targets for surface-to-air missiles (SAMs) in case one of them came down in a public area. The flights demonstrated that the modifications did not compromise the Firebee's performance.
Ryan actually wanted to build a completely new drone, the Ryan Model 136, for the reconnaissance mission. The Model 136, or Red Wagon, was optimized for the role with long straight wings for high-altitude flight, an engine set on the back of the fuselage to reduce its radar and infrared signatures as seen from below, and inward-canted twin tail fins to conceal the exhaust plume. The project stalled, however as the incoming Kennedy Administration was certain to reassess many military projects and Red Wagon was put on hold.