Lockheed SR-71 Blackbird: The world's fastest flying legend

Close-up of the legendary Mach 3 at the Smithsonian Museum

The Lockheed SR-71 Blackbird is considered one of the most extraordinary aircraft ever to fly. Its incredible speed and beautiful design make it an aeronautical masterpiece.

The famed reconnaissance aircraft holds the record for being the fastest jet in the world, outpacing most other reconnaissance, surveillance and intelligence gathering assets.

The SR-71 Blackbird made its first flight in 1964, during the height of the Cold War. It served for 24 years with an impressive record. According to the National Museum of the United States Air Force, the SR-71 remains the world's fastest and highest-flying operational aircraft.

On July 28, 1976, the SR-71 set two world records for its class: an absolute speed of 2,193.167 mph and an absolute altitude of 85,068.997 feet.

Pioneering design of the SR-71 Blackbird

The SR-71 Blackbird's shape was not simply a product of the aerodynamic requirements for high-speed missions, combined with the enormous fuel capacity required for long-range flights. Many of its features were primarily stealth features, designed to deflect radar waves.

The US government was really focused on creating a stealth aircraft. The chine, the slanted tail, and the shape of the underside of the aircraft all contributed to deflecting radar energy. However, even with the addition of RAM, the techniques of the time were not enough to make the Blackbird truly stealthy. But the techniques were refined over the years, leading to the first truly stealth aircraft in the 1970s.

Michael Hankins, curator of the Smithsonian National Air and Space Museum's collection of 30 post-World War II aircraft, talks about the groundbreaking technology of the SR-71 Blackbird.

The Blackbird’s most closely guarded secret was its stealth features. Much of the aircraft’s shape was designed to deflect radar waves, combined with radar absorbent material (RAM) placed at key locations to absorb radar energy. While not quite as stealthy as technology in the early 1960s would allow, the SR-71 laid the groundwork for stealth aircraft that would come later.

Unique engine and navigation technology

The Astroinertial Navigation System undertakes the complex task of accurately tracking an aircraft's position at high speeds using astronomical positioning.

There was no GPS back then, and navigation in the air was always a challenge. The computer system, located just behind the RSO cockpit, scanned the sky for stars. Based on their movement, the system calculated the plane’s position to within 300 feet when flying at Mach 3.

After the release of the movie Star Wars in 1977, the crew began calling the ANS system by the nickname "R2-D2".

The SR-71 Blackbird's engines and intake/cooling systems were highly advanced. The Pratt & Whitney J58 engines operated as turbojets at low speeds, and transitioned to near-ramjet mode at hypersonic speeds, allowing the aircraft to maintain a steady top speed.

Stunning flying experience at extreme altitude

SR-71 Blackbird crews shared that the mission required intense concentration. Flying the aircraft and handling reconnaissance and navigation missions required a great deal of concentration. According to many pilots, the most difficult part of flying the SR-71 was maintaining constant concentration. Flights often lasted for hours with multiple mid-air refuelings.

Almost all of the crew spoke of the amazing experience of flying. Flying at such high altitudes, seeing the curvature of the Earth, seeing the edge of space, and traveling at such speeds was an incredibly exhilarating experience according to most.

High operating costs lead to early retirement

The biggest factor in the SR-71 Blackbird’s decommissioning was cost. Operating costs were astronomical, estimated at more than $85,000 per flight hour (equivalent to over $260,000 today). As satellites and drones proliferated, maintaining a fleet of Blackbirds became unaffordable.