The SR-71 Blackbird

15 January, 1972. Four Soviet MiG-25 interceptors race skywards, intercepting a lone American aircraft violating their airspace. These MiGs are the world's premier interceptors, easily capable of reaching 2.8 times the speed of sound and launching four massive long-ranged R-40 missiles. Their radar sets so powerful they burn through any jamming signals sent out by enemy aircraft. But the plane they are trying to intercept flies too high and too fast. Missiles are launched. A green flash is seen high in the sky as the mysterious plane lights its afterburner and outruns the missiles. The lone aircraft continues on it mission through Soviet airspace, completely untouchable.

Beginnings

The SR-71 was born out of a need for a successor to the venerable Lockheed U-2 spy-plane. At the time of its introduction the U-2 was revolutionary, flying above any and all air defense, but now, in 1958, Soviet air defense had gotten exponentially better. The U-2 was now a slow sitting duck. The CIA contacted the builders of the U-2, Lockheed, to design a revolutionary undetectable spy plane. The project was given the (really cool) codename Archangel. The program proceeded slowly until the downing of Gary Powers' U-2 over the USSR highlighted the need for a better plane. On April 25, 1962, the A-12 flew for the first time at Groom Lake (Area 51), the top-secret testing grounds for confidential aircraft.

The single-seat design was modified for the Air Force to become the SR-71 Blackbird (SR for "strategic reconnaissance") under the cover story that it was a new interceptor (called the YF-12). Quick fact: a few YF-12's were built, with missile bays replacing the spy equipment, but none were ever deployed in combat patrols.

Design

Speed was first and foremost in the development of the Blackbird, something that even a quick glace can show. It's two massive Pratt & Whitney J58 turboramjets could switch from a normal jet engine to a ramjet at high speeds, and the pointy inlet cones could move 26 inches forwards and backwards for optimal something something supersonic something shock-wave compression something (They would move to reflect the shockwave from the tip of the spike to the edge of the intake, passively slowing the air down while keeping the drag very low).

Yeah, I don't know either

The aircraft was also designed to be low-observable and partially stealth. This can be seen from the rounding of the fuselage and the inward cant of the tail-fins. The dark-blue, almost black paint was applied to make the plane blend into the black sky at the edge of space. Speed had a disadvantage: at mach (a measure of speed; mach 1 is the speed of sound) 3.2, the skin of the plane heated up to 500 Celsius. Normal aviation fuel would explode in the tanks at this temperature. Instead of redesigning the airframe, a new low-volatility fuel blend was created, JP-7. It acted as a heat-sink for internal components, as fuel for the thirsty J58's, and was the hydraulic fluid for the engine hydraulics. The pilots of the SR-71 were equipped with a pressure suit to keep them alive in case of an emergency ejection.

Flying at the edge of space

The heat mentioned above added another problem to the design. Any normal structural metal would melt at that temperature. Titanium was the only metal light and structural enough to be used. The only issue was that the US had hardly any titanium. You know who had titanium though? The Soviet Union. So through third-world countries and other shady means the US bought/stole enough titanium to make 32 planes from the Soviets.

The production floor at Lockheed's Skunk Works

Performance

Top speed at altitude: Mach 3.3 (2000 mph / 3200 kph)

Service altitude: 80,000 feet Above Sea Level
Maximum altitude: 85,000 feet ASL

Range: 2900 miles for most missions

Records

The SR-71 set lots of records (some which still stand today) due to its crazy performance.

Absolute Altitude: 85,069 feet

Absolute Speed: 2,193.2 mph

New York to London: 1 hour, 54 minutes, 56.4 seconds (A 747 takes about 6 hours 57 minutes for the same route)

Its safety record was another thing altogether. Although none were ever shot down, 12 out of the 32 built were lost in accidents.

One notable accident occurred when the automatic control system for the inlet spikes failed on a training flight over the Southwestern US, causing the engine to 'unstart' (basically stop) because the shockwaves were going into it instead of being bounced away by the spike. This was accompanied by a large bang, and the aircraft pitching up and turning sharply to the right. In the words of pilot Bill Weaver, "I instantly knew we were in for a wild ride." The aircraft lost control at Mach 3.18 (2039 mph) and an altitude of 78,000 feet. The combination of extreme speed and a sharp turn created huge g-forces, and only 3 seconds after the unstart the pilot blacked out. "The SR-71 then literally disintegrated around us." He awoke at about 20,000 feet, free falling."I realized that this was no dream; it had really happened. That also was disturbing, because I could not have survived what just happened." He landed on a desert plateau and was quickly picked up by a rancher. A later investigation found that the eject sequence was never activated. Both the pilot, Bill Weaver and the reconnaissance and navigation specialist Jim Zwayer were ripped from the aircraft from the high-g's. Weaver's harness was still attached to his pressure suit, the high-strength nylon belts ripped from their latches on the sides of the seat.