World Library  
Flag as Inappropriate
Email this Article

Ryan AQM-91 Firefly

Article Id: WHEBN0006280138
Reproduction Date:

Title: Ryan AQM-91 Firefly  
Author: World Heritage Encyclopedia
Language: English
Subject: Boeing YQM-94, List of missiles by country, ADM-144, AGM-63, RIM-85
Publisher: World Heritage Encyclopedia

Ryan AQM-91 Firefly

AQM-91 Firefly
Teledyne Ryan AQM-91A Compass Arrow at the National Museum of the United States Air Force.

The Ryan AQM-91 Firefly was a developmental drone developed during the Vietnam War to perform long-range reconnaissance, especially into China.


The Ryan Model 147 Lightning Bug reconnaissance drone was enjoying success in Vietnam in the early 1960s, but it lacked the range to fly deep into China and back out again. In particular, the Chinese nuclear development facility at Lop Nor was far out of reach of the Lightning Bugs, and was barely within reach of the Lockheed U-2 spyplane, which had become far too vulnerable to SAMs. US intelligence thus needed a long-range drone with a high degree of survivability. Such requirements spelled out a completely new design, not a modification of a target drone.

Ryan pursued advanced drone concepts on a part-time basis. After discussions with the CIA that went nowhere, Ryan pitched their advanced reconnaissance drone concepts to the Air Force in early 1966. The USAF was interested, and opened up a design competition, with Ryan competing with North American Aviation. Ryan won the competition in June 1966, and the new design was designated the "Model 154 / AQM-91A Firefly". The basic design concept resembled that of the Model 136 Red Wagon drone that Ryan had proposed earlier in the decade, but which had been turned down in favor of a modified Firebees. The name "Firefly" was resurrected from the early Model 147 program for the new drone, though it was also referred to as "Compass Arrow" after the program name. The test flights were conducted over the US Southwest. The project was highly secret, but on 4 August 1969 one of the prototypes failed and parachuted to ground inside the Los Alamos nuclear research complex during lunch hour. Unfortunately, it didn't land in a restricted area, and local newspeople were able to take and publish photographs of the aircraft. The Air Force released a statement that the aircraft was a "high altitude target", but though such a statement might have been believed in 1959, it wasn't in 1969.

Test flights were halted for a few weeks while procedures were reviewed. The flights then resumed, culminating in long-range evaluations in late 1971. The Model 154 passed with flying colors, exceeding its altitude requirements by a good margin, and proving almost invisible to radar. However, by this time the need for the Model 154 had vanished. In July 1971, President Richard Nixon began a diplomatic effort to build ties with China, and reconnaissance overflights were cancelled. Satellite reconnaissance capabilities had improved through the 1960s, leading to the first launch of the advanced KH-9 Hexagon satellite on 15 June 1971, which could provide strategic intelligence without provoking the Chinese.

The Model 154 program lingered on for a few more years, but the drones were finally put into mothballs in 1973, and scrapped a few years after that. 28 had been built, including 20 production machines.



The Model 154 had an engine on the top of the fuselage to reduce its radar cross-section and infrared signature as seen from below, as well as twin inward-canted tailfins to conceal the exhaust stream. It had sloped flat sides to deflect radar signals, and was built using a high percentage of plastic composite materials, which had a lower radar reflectivity than metal (see radar-absorbent material). The aircraft was powered by a General Electric YJ97-GE-3 turbojet providing 4,000 pounds (1,815 kg) thrust, with the engine exhaust mixed with cool air to reduce its infrared signature. The YJ97 was derived from a General Electric demonstrator engine designated the "GE1".


The Model 154 was to be launched by a DC-130 Hercules director aircraft, and recovered in midair by helicopter. It had a precision-navigation autopilot system, a reconnaissance payload, a self-destruct system to ensure that none of its sensitive gear fell into enemy hands, and was to carry electronic countermeasures to further improve its survivability. The primary reconnaissance payload was an Itek panoramic camera, but in principle it could also carry thermographic camera or a Signals intelligence payload.

The guidance system was designed to provide navigation accuracies with an error of no more than half a percent. The guidance system proved to be very tricky, and first powered flight of a Model 154 did not take place until September 1968.


See also

Related development


  • This article contains material that originally came from the web article Unmanned Aerial Vehicles by Greg Goebel, which exists in the Public Domain.

External links

  • Teledyne Ryan AQM-91 Firefly
  • AQM-91A USAF Fact Sheet
  • Stealth. 80,000ft. $375 Million A Copy. Did We Say This Was In 1970?
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.