The SR-71 Blackbird

By Dhruv Golchha

History

The SR-71 was born as the A-12, from a US military contract to replace the slow, high-flying U2 reconnaissance spy plane. The U2 flew at immensely high altitudes of 70,000 feet to avoid detection and interception. However, in a fateful incident on the 1st of May, 1960, a U2 took off from Pakistan to fly deep into the USSR, destined to finally come within the grasp of Soviet Surface-to-Air Missiles. That day, the U2 was shot down and recovered by the Soviets, embarrassing the US and heightening tensions in the Cold War.

The CIA contract was for a plane that flew even higher than the U2, at 3 times the speed of sound, and had reduced radar visibility. Lockheed Martin, the same contractor which produced the U2, was awarded the contract to develop such a plane, named the Archangel. The engineers over at Skunk Works, Lockheed’s top secret and elite department, began to work on various designs, settling on the A-12 Archangel. Able to fly at Mach 3.35+, at 95,000 feet, and with a radar cross section of just 10 m2 (about the size of a large eagle), this design was everything the CIA hoped for, and they ordered it in early 1960, under the moniker project Oxcart.

Production and Technology

To produce the A-12, Lockheed had to invent a variety of new manufacturing techniques and materials. At the Archangel’s speeds, the surface would heat up to over 300°C, too hot for conventional materials like Aluminum. Titanium alloys were settled upon as the only viable material, lightweight, strong, and heat resistant, they were the perfect material for the A-12.

The leading producer of titanium at the time was the Soviet Union. To bypass this hurdle, the CIA set up multitudes of shell companies to disguise their purchase of titanium.

The SR-71

The SR-71s were the USAF’s final iteration of the Archangels. The budget burden was shared with the 2 departments throughout the project, but the SR-71s were the first planes on a production line for the Air Force. Aptly nicknamed Blackbird due to their black stealth paint, they entered service in 1967, leading to the retirement of the Archangels.

The Blackbird was longer, slightly heavier, crewed 2 instead of Archangel’s 1, and flew a little lower and slower. While the Archangels were top secret, the Blackbirds were public, and immensely popular.

It set world records, the highest absolute altitude at 85,069 feet, absolute speed at 3529.6 km/h, and fastest flight from New York to London, in 1:54:56.4. Various pilot reports place the top speed of the aircraft even beyond the declassified limit of Mach 3.2; with one pilot stating that he comfortably took it to 3.5M on one mission.

It flew 11,000 hours over 3551 missions, flying over Vietnam, Korea, China, the middle East, Cuba, Iran, and Eastern Europe. It was essential in winning the Cold War and maintaining peace from its first flight in 1964 to its final retirement in 1998.

From the day of its birth, it has held a special place in the hearts of all aviation lovers, as the fastest and highest plane there ever was, a wonder of engineering, and a beast far ahead of its time.

“You haven’t been lost till you’ve been lost at Mach 3!” - Frank Stampf.