Lockheed SR-71 Blackbird: Difference between revisions

[[JP-7]] fuel was used. It was difficult to ignite. To start the engines, [[triethylborane]] (TEB), which [[pyrophoricity|ignites on contact with air]], was injected to produce temperatures high enough to ignite the JP-7. The TEB produced a characteristic green flame, which could often be seen during engine ignition.<ref name="Shul"/> A chemical ignition system was also required as there was no fuel available as a heat sink for cooling electrical ignition components. The fuel had to be used for cooling the pilot and aircraft electronics.<ref>J58/SR-71 Propulsion Integration Or The Great Adventure Into The Technical Unknown, William Brown, Pratt & Whitney Aircraft Group, attachment to CIA-RDP90B00170R000100050008-1</ref>

On a typical mission, the SR-71 took off with only a partial fuel load to reduce stress on the brakes and tires during takeoff and also ensure it could successfully take off should one engine fail.<ref>{{harvp|Graham|1996|p=16046}}</ref> Within 20 seconds the aircraft traveled {{convert|4500|ft}}, reached {{convert|240|mph}}, and lifted off. It reached {{convert|20000|ft}} of altitude in less than two minutes, and the typical {{convert|80000|ft}} [[cruising altitude]] in another 17 minutes, having used one third of its fuel.{{r|iwm20211103}} It is a common misconception that the planes refueledrefuelled shortly after takeoff because the jet fuel tanks, which formed the outer skin of the aircraft, leaked on the ground. TheIt leakingwas ofnot fuelpossible to prevent leaks when the aircraft skin was causedcold byand the tanks only sealed when the skin heated up as the aircraft speed increased. The failureability of the sealant due to theprevent highleaks heatwas andcompromised by the expansion duringand contraction of the skin with each flight.<ref>{{cite web |last1=Boudreaux |first1=Stormy |title=The SR-71 Experience |url=https://www.youtube.com/watch?v=J5qrMTtSUV8&t=2129s |website=YouTube |publisher=Air Zoo |access-date=17 September 2023}}</ref> However, the amount of fuel that leaked, measured as drops per minute on the ground from specific locations, was not enough to make refuelingrefuelling necessary; the planes refueledrefuelled because the maximum speedsspeed of the aircraft werewas only possible with aerial refuelingrefuelling.<ref>{{harvp|Graham|2013|p=110}}</ref>

The SR-71 also required [[Aerial refueling|in-flight refueling]] to replenish fuel during long-duration missions. Supersonic flights (Acoustically closed and only Engine Vibrations are heard) generally lasted no more than 90 minutes (within Magneto-Sphere) before the pilot had to find a tanker.<ref>Marshall, Elliot, The Blackbird's Wake, Air and Space, October/November 1990, p. 35.</ref> Flight higher than that last longer for the Black Bird gains speed and Momentum and Engines are turned to lower RPM (e.g. Gauge, Thrusters).

The first flight of an SR-71 took place on 22 December 1964, at USAF [[Plant 42]] in [[Palmdale, California]], piloted by Bob Gilliland.<ref>{{Cite web|url=https://www.kesq.com/news/first-man-to-fly-the-world-s-fastest-aircraft-dies-in-rancho-mirage/1092463937 |title=First man to fly the world's fastest aircraft dies in Rancho Mirage |first=Jesus |last=Reyes |date=6 July 2019 |website=KESQ |access-date=6 July 2019 |archive-url=https://web.archive.org/web/20190706041642/https://www.kesq.com/news/first-man-to-fly-the-world-s-fastest-aircraft-dies-in-rancho-mirage/1092463937 |archive-date=6 July 2019 |url-status=dead}}</ref><ref>{{harvp|Crickmore|1997|pp=56-58}}.</ref> The SR-71 reached a top speed of Mach 3.4 during flight testing,<ref>{{cite web |last= Graham |first=Richard |title=SR-71 Pilot Interview Richard Graham, Veteran Tales interview at Frontiers of Flight Museum (at 1:02:55) |url=https://www.youtube.com/watch?v=CeBu6mRDaro#t=3775 |work=YouTube |date=6 August 2013 |publisher=Erik Johnston |access-date=29 August 2013 |ref=none}}</ref><ref>{{cite web |title=Col. Richard Graham (USAF, Ret.) |url=http://www.habu.org/graham/graham-bio.html |publisher=The Online Blackbird Museum |website=Habu.org |access-date=16 January 2016}}</ref> with pilot Major [[Brian Shul]] reporting a speed in excess of Mach 3.5 on an operational sortie while evading a missile over Libya.<ref name="Shul M3.5">{{cite book |last=Shul |first=Brian |title=The Untouchables |year=1994 |publisher=Mach One |isbn=0929823125 |page=173}}</ref> The first SR-71 to enter service was delivered to the [[9th Reconnaissance Wing#Beale Air Force Base|4200th (later, 9th) Strategic Reconnaissance Wing]] at [[Beale Air Force Base]], California, in January 1966.<ref>{{harvp|Crickmore|1997|p=59}}</ref>

* {{Cite book |last=Graham |first=Richard H. |title=SR-71 Blackbird: Stories, Tales, and Legends |date=2002 |publisher=Voyageur Press |isbn=0-7603-1142-0}}

* {{Cite book |last=Graham |first=Richard H. |title=SR-71: The Complete Illustrated History of the Blackbird, The World's Highest, Fastest Plane |date=2013 |publisher=MBI Publishing Company |isbn=978-0760343272}}

* {{Cite journal |last=Merlin |first=Peter W. |title=The Truth is Out There... SR-71 Serials and Designations |journal=[[Air Enthusiast]] |volume=118 |date=July 2005 |publication-place=Stamford, UK |publisher=Key Publishing |pages=2-62–6 |issn=0143-5450}}