We Look At The SR71 Blackbird

We Look At The SR71 Blackbird

We Look At The SR71 Blackbird: Even though it was built at the height of the Cold War and hasn’t flown in over 17 years, the SR-71 Blackbird still looks like it fell out of the future. The war plane with no weapons not only had the lines of a spaceship, it set the record for the fastest air-breathing manned aircraft in 1976 – a record that remains unchallenged to this day. So how was it built, and what was it like to fly this supersonic denizen of the edge of space? Developed by Lockheed at its famously secretive Skunk Works in Burbank, California, the SR-71 was a derivative of the A-12 reconnaissance plane built for the CIA as a replacement for the U2 spy plane of the 1950s. It was the brainchild of American aerospace engineer Clarence “Kelly” Johnson who, like a real-life Tony Stark, came up with all sorts of remarkable design innovations that pushed forward aerospace engineering.  The surviving Blackbirds now reside in aerospace museums and air force bases in the United States and Britain, but it’s still one of those planes that looks like it would leap into the sky if you turned your back on it. Despite being a recon aircraft, the SR-71 isn’t a small airplane. At 107.4 ft (32.74 m) long with a wingspan of 55.6 ft (16.94 m) and standing 18.5 ft 6 (5.64 m) high, it tends to dominate any museum gallery it sits in. Empty, it weighs 67,500 lb (30,600 kg) and when fueled and loaded with its payload of sensors, it tipped the scales at 152,000 lb (69,000 kg).

In fact, the SR-71 was the largest item anyone had ever attempted to make out of titanium up until that time. That caused all sorts of problems. For a start, titanium is a rare metal and there wasn’t enough being produced in the US to build the Blackbirds, so the Americans used third parties and dummy companies to secure titanium from abroad, including from the Soviet Union. This wasn’t helped when at one point 80 percent of the titanium bought turned out to be substandard. SR-71 wasn’t just an advanced bit of titanium forging. It was also one of the first warplanes designed to take off and disappear. Everything about the Blackbird was engineered to make it as invisible as possible. For example, its famous dark livery wasn’t meant to make it look like something out of Batman’s garage – it had a very practical purpose. And despite its name, the Blackbird wasn’t actually painted black, but a very dark blue, so it would blend into the night sky.

All this stealth paid off, with the SR-71 having a 10 m2 (108 ft2) radar cross-section – roughly that of a J-3 Piper Cub prop plane. In addition, the fuel was laced with cesium to make the exhaust plumes less visible to radar. Along with state of the art jamming equipment, these elements combined to make the plane almost invisible, but it was a constant race with the Soviets that was difficult to keep ahead of. When all of this was put together, the Air Force had one incredible machine. It’s two Pratt & Whitney J58-1 engines could each punch 34,000 lbf (151 kN) of thrust and at 85,000 ft (25,900 m) it could reach a maximum speed of Mach 3.3 (2,200+ mph, 3,540+ km/h, 1,910+ knots). Though its range was only 2,900 nm (3,337 mi, 5,400 km), it could be refueled in-flight, so its only limit was the endurance of the crew. Heat was a constant problem for the SR-71, which grew so hot that when it landed the ground crews had to careful not to burn themselves on its skin. The engine used a special lubricating oil that remained stable at 600⁰ F (315⁰ C) and the windscreens were made of quartz to survive equally high temperatures. To keep the engine and other systems cool, the fuel was cycled inside to the chines, which acted as radiators.

We Look At The SR71 Blackbird

 

You may also like...