LOCKHEED SR-71 BLACKBIRD
Twin-engine, two-seat, supersonic strategic reconnaissance aircraft; airframe constructed largley of titanium and its alloys; vertical tail fins are constructed of a composite (laminated plastic-type material) to reduce radar cross-section; Pratt and Whitney J58 (JT11D-20B) turbojet engines feature large inlet shock cones.
No reconnaissance aircraft in history has operated globally in more hostile airspace or with such complete impunity than the SR-71, the world's fastest jet-propelled aircraft. The Blackbird's performance and operational achievements placed it at the pinnacle of aviation technology developments during the Cold War.
This Blackbird accrued about 2,800 hours of flight time during 24 years of active service with the U.S. Air Force. On its last flight, March 6, 1990, Lt. Col. Ed Yielding and Lt. Col. Joseph Vida set a speed record by flying from Los Angeles to Washington, D.C., in 1 hour, 4 minutes, and 20 seconds, averaging 3,418 kilometers (2,124 miles) per hour. At the flight's conclusion, they landed at Washington-Dulles International Airport and turned the airplane over to the Smithsonian.
Because the aircraft was designed to fly faster than 2,000 mph, friction with the surrounding atmosphere would heat up the fuselage to a point that would melt a conventional airframe. The plane was therefore made of titanium, a metal that was able to withstand high temperatures while also being lighter than steel.
Using titanium presented other problems, however. First, a whole new set of tools -- also made of titanium -- had to be fabricated, because regular steel ones shattered the brittle titanium on contact. Second, sourcing the metal itself proved tricky. "The USSR was, at the time, the greatest supplier of titanium in the world. The US government had to purchase a lot of that, probably using bogus companies," said Merlin.
The initial aircraft were flown completely unpainted, showing a silver titanium skin. They were first painted black in 1964, after the realization that black paint -- which efficiently absorbs and emits heat -- would help lower the temperature of the entire airframe. The "Blackbird" was born.
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