Even as the SR-71 sits in museums rotting away, she still holds countless speed records. No wonder there is so much talk of an SR-72: On April 2 and 3, the March Field Air Museum in Riverside, California, hosted its “SR-71 Weekend,” which brought together 20 former pilots of the legendary SR-71 “Blackbird” as well as reconnaissance systems operators (RSOs), maintainers and engineers. “Cockpit discussions” were led by retired SR-71 pilot Lt. Col. Jerry Glasser and retired RSO Col. John Manzi. They shared their experiences of flying the most impressive of Cold War-era aircraft.
Known unofficially as the “Blackbird” for its black paint job, which was developed to dissipate heat, the SR-71 featured sleek lines that may have seemed “futuristic” when it was flying top-secret missions years before American astronauts headed to the moon. The aircraft was able to achieve a record top speed of 2,193 mph – and while other aircraft could reach such extreme speeds in theory – and could melt due to the atmospheric friction and heat – the Blackbird could maintain it for extended periods. It still holds the record for a cross-country flight, traveling from Los Angeles to Washington, D.C. in just 64 minutes, 20 seconds.
In addition to flying fast, the SR-71 also set an altitude record – reaching 25,929 meters. Developed in secret in the late 1950s, the SR-71 cruised to 80,000 feet above the earth, near the edge of space, and out fly any missile that was launched at it.
Enter the SR-71
The aircraft was born out of the Lockheed “Skunk Works,” which had a proven track record during the Cold War to delivering “impossible” technologies on an incredibly short, but strategically critical deadline. The goal of this project was very much to stop a potential war and safeguard the United States by allowing it to determine what our potential adversaries might be up to.
The Central Intelligence Agency (CIA) and United States Air Force called for a new plane that could operate at extreme altitudes, speeds, and temperatures. However, that meant that everything from the tires, oil, fuel, and even paint had to be created from the ground up. The SR-71 project was headed up by Kelly Johnson, one of the preeminent aircraft designers of the twentieth century, who suggested, “Everything had to be invented. Everything.”
And he meant everything.
The aircraft was the first to utilize titanium alloy – which provided the strength of steel but at a relatively lightweight –for the airframe. Along with its low weight, titanium was the only material that could provide the durability of stainless steel at excessive temperatures.
However, at the time the United States didn’t have any major sources of metal, nor did any U.S. allies. The titanium used in the aircraft ended up being sourced from the same nation the aircraft was used to spy on – namely the Soviet Union! The raw materials were bought from third-world countries and fake companies.
“The airplane is 92% titanium inside and out. Back when they were building the airplane the United States didn’t have the ore supplies – an ore called rutile ore. It’s a very sandy soil and it’s only found in very few parts of the world. The major supplier of the ore was the USSR. Working through Third World countries and bogus operations, they were able to get the rutile ore shipped to the United States to build the SR-71,” former SR-71 pilot Colonel Rich Graham told the BBC.
It wasn’t just obtaining the titanium. There was also a major concern that the use of cadmium-plated steel tools could weaken the body of the aircraft if mishandled, which meant that even new tools had to be designed and fabricated. Those too were made from titanium.
Flying High
The Blackbird, which first took flight in 1964, could enter hostile airspace, take photographs from those extreme heights like a tourist on vacation and still be on its way before an enemy had a chance to even take a shot at it. While it could cross continents in just a few hours, the aircraft also flew so high that pilots navigating by sight couldn’t rely on ground features such as roads and instead needed to look at the mountains, rivers, and major coastlines to get their bearings.
During its operational lifetime, the SR-71 provided intelligence about the Yom Kippur War in 1973, the Israeli invasion of Lebanon in 1982, the American air forces’ raid on Libya in 1986, and the revelation of Iranian Silkworm missile batteries in 1987.
Thanks to its speed and other capabilities, not a single SR-71 was ever shot down – yet a dozen were lost in accidents.
However, it wasn’t exactly a joy to fly. Pilots had to wear special suits to protect them from the extreme temperatures, and it has been reported that the glass on the cockpit would get so hot that meals could be heated upon it.
Unlike combat aircraft, which could be “scrambled” and in the air within minutes, the SR-71 – “Strategic Reconnaissance” – was more like a space launch of the era. To get the Blackbird into the sky took hours of preparation and a large team to ensure everything was in order.
The aircraft was also known to leak fuel, but it was actually designed to do so. The SR-71 didn’t use standard aviation fuel, but a special military specification fuel called MIL-T 38219, or Jet Propellant 7. Shell Oil was called upon to invent a compound blend to meet the military’s requirements, and the result was three times as expensive as the type of fuel used by airliners of the era.
SR-71 Blackbird Spy Plane. Image Credit: Creative Commons.
Image is of an SR-71 Spy Plane. Image Credit: Creative Commons.
Image of SR-71 Spy Plane. Image Credit: Creative Commons.
In addition, the titanium fuselage panels were also loosely fitted to the aircraft’s frame to allow for heat expansion, while the fuel system was also not sealed because there were no seals that were flexible and durable enough to deal with the kind of temperatures and shrinking-expansion cycles. As a result, the plane would leak fuel while on the runway, but it would stop leaking once the aircraft came up to temperature!
The SR-71 had to be refueled right after takeoff, and it wasn’t just because of the leaks. JP-7 reached temperatures over 300 degrees F during the Mach 3 cruise, which made the fumes in each of the six fuel tanks very volatile and potentially explosive. Taking off with less fuel was safer.
Today some surviving Blackbirds in museums still leak fuel, as noted by visitors who can see wet spots – and possibly smell the JP-7.
Now a Senior Editor for 1945, Peter Suciu is a Michigan-based writer who has contributed to more than four dozen magazines, newspapers and websites. He regularly writes about military hardware, and is the author of several books on military headgear including A Gallery of Military Headdress, which is available on Amazon.com. Peter is also a Contributing Writer for Forbes.
