Lockheed YF-12
| Lockheed YF-12 | |
|---|---|
 YF-12 (S / N 60-6934) during a test flight |
|
| Type: | Interceptor |
| Design country: | |
| Manufacturer: | |
| First flight: |
7th August 1963 |
| Commissioning: |
no |
| Production time: |
no series production |
| Number of pieces: |
3 prototypes |
The Lockheed YF-12 was a twin -engine test aircraft from Lockheed for the United States Air Force , which was derived from the Lockheed A-12 OXCART altitude reconnaissance aircraft . Only three copies of the interceptor were built before the program ended. In the Lockheed Advanced Development Projects Unit , better known as Skunk works , chief designer Clarence Johnson developed the YF-12. It is the world's largest fighter aircraft ever built .
history
After the construction of the North American XF-108 interceptor had been stopped for financial reasons, Lockheed succeeded in getting the Air Force interested in a Mach 3 interceptor derived from the A-12. The aircraft was intended to replace the Convair F-106 Delta Dart . With the CIA facing cost overruns on the A-12 program, the Air Force decided to have three machines completed in the configuration for an interceptor. On August 7, 1963, the first YF-12 flew. A purchase of 93 further modified YF-12Bs was stopped in 1965 by Defense Secretary Robert McNamara . In addition to cost reasons, it was also stated that the Soviet Union did not have any bombers that would justify such fast interceptors.
For 5 years, from 1959 to 1964, the entire program was kept secret and even the application category of the design remained hidden. In the election year of 1964, the development, then known as the A-11, was revealed to the public, with the President and Secretary of Defense contradicting the role of the aircraft: On February 29, 1964, President Johnson presented the aircraft as a long-range fighter. Then a veil of secrets was drawn again, only to present the completely new version SR-71 as a strategic reconnaissance aircraft a short time later. On September 30, the fighter version was presented under its name YF-12A. In December 1964, the trade magazine Interavia reported that 8 of the Interzepter version had been built to date and a further twelve had been ordered.
Of the three YF-12s actually built, one still exists today. This is in the National Museum of the United States Air Force on Wright-Patterson Air Force Base . Another aircraft was badly damaged in a failed landing in 1966 by a fire at Edwards Air Force Base and was later converted into the only SR-71C Blackbird . The third machine was lost on June 24, 1971 after a fire during the flight, the pilots were able to save themselves using an ejector seat .
construction
The YF-12 was essentially an A-12, so it also had a fuselage that was mainly made of titanium and two Pratt & Whitney J58 engines that could accelerate the YF-12 to speeds of over Mach 3. However, the YF-12 has been changed compared to the OXCART, especially in terms of equipment . The nose was modified to accommodate a Hughes AN / ASG-18 radar , and the camera bays were converted into missile bays. Each YF-12 had three air-to-air missiles of the type AIM-47 Falcon carrying.
Records
With the third prototype of the YF-12A (Article 1003, AFSN 60-6936 ), the following records were set on May 1, 1965 on four flights from Edwards AFB: speeds on circuits over 500 km (2644.596 km / h) and 1000 km (2718.006 km / h) by Major Walter F. Daniel, speed over a straight course of 15/25 km (3331.507 km / h) and reached altitude in level flight 24,462.596 m by Colonel Robert L. Stephens . The records on the 500 and 1000 km circuits were broken two years later (October 1967) by Je-266 , the two other records by the SR-71 (July 28, 1976).
Technical specifications
| Parameter | Data |
|---|---|
| Type | High-speed interceptors |
| crew | 2 |
| length | 30.97 m |
| span | 16.95 m |
| height | 5.64 m |
| Wing area | approx. 167 m² |
| Empty mass | 27,604 kg |
| Max. Takeoff mass | 63,504 kg |
| Top speed | 3332 km / h |
| Max. Altitude | approx. 25,000 m |
| Range | 4830 km (without refueling) |
| Engine | Two Pratt & Whitney J58 turbojet engines with afterburners and each 144.57 kN thrust |
| Armament | up to three AIM-47 Falcon air-to-air missiles |
See also
literature
- James Goodall: Lockheed's SR-71 "Blackbird" Family -A-12, F-12, D-21, SR-71. Midland 2003; ISBN 978-1-85780-138-5
Web links
- YF-12 on nationalmuseum.af.mil (engl.)
Individual evidence
- ↑ Steve Pace: X-Planes at Edwards 1995, ISBN 978-1-61060-786-5 , p. 11.
- ^ The A-11: New US Jet is Fastest and Highest , Time, March 13, 1964, p. 25
- ↑ America's fastest and most discussed military aircraft: YF-12A , Interavia No. 12/1964, p. 1806
- ^ Dave Butt: YF-12A 60-6936. In: Online Magazin for Aviation Enthusiasts Airforce / Military / Tribute. Photorecon.net , July 12, 2014, accessed December 13, 2019 .
- ^ Fédération Aéronautique Internationale : Record: Walter F. Daniel (USA). Entry of the achieved speed of a class C aircraft over a closed course of 500 km; C1 (land plan). FAI World Air Sports Federation, October 10, 2017, accessed December 12, 2019 .
- ^ Fédération Aéronautique Internationale : Record: Walter F. Daniel (USA). Entry of the achieved speed of a class C aircraft over a closed course of 1000 km; C1 (land plan). FAI World Air Sports Federation, October 10, 2017, accessed December 12, 2019 .
- ^ Fédération Aéronautique Internationale : Record: RL Stephens (USA). Entry of the achieved speed of a class C aircraft over a course of 15/25 km; C1 (land plan). FAI World Air Sports Federation, October 10, 2017, accessed December 12, 2019 .
- ^ Fédération Aéronautique Internationale : Record: RL Stephens (USA). Entry on the achieved height of a class C aircraft in level flight; C1 (land plan). FAI World Air Sports Federation, October 10, 2017, accessed December 12, 2019 .