In a different category from anything that had come before
The legendary SR-71, which earned its nickname “Blackbird,” emerged as a long-range, Mach 3+, strategic reconnaissance aircraft that Lockheed developed from the A-12 and YF-12A aircraft.
The first flight of an SR-71 took place on Dec. 22, 1964, and it was in January 1966 when the first operational SR-71 joined the 4200th (later 9th) Strategic Reconnaissance Wing at Beale Air Force Base, Calif.
The speed of the SR-71 exceeded 2,000 mph. Other planes of the era could, in theory, approximate that speed but only in short, after-burner-driven bursts. The Blackbird maintained a record-setting speed for hours at a time. At such velocity, friction with the atmosphere generates temperatures that would melt the conventional airframe.
The Blackbird was in a different category from anything that had come before. “Everything had to be invented. Everything,” Skunk Works legendary aircraft designer Kelly Johnson recalled in an interesting article that appeared on the Lockheed Martin website.
The SR-71 Blackbird periscope
For instance, few know that the SR-71 had a periscope that was used on every flight. It only stuck up about 2 inches. When it is open, you can look for it on the top of the SR-71. It looks like a very tiny little crown.
According to SR71Blackbird.org, the periscope was positioned directly above the pilot, providing him with critical views of the Blackbird’s dorsal surfaces, including vertical fins, engines, and aft fuselage.
I recently asked SR-71 Pilot Stormy Boudreaux about the periscope, where it was, and how often he used it when he flew the SR-71, and this was his answer.
‘It (the periscope) was used several times during each climb and once or twice during the cruise. If I had an unstart*, it showed me that the Afterburner [AB] had blown out—an often result after an unstart.
‘When the AB blew out, the fuel to the afterburner continued to flow without being lit.
‘So, I had to pull that throttle out of the AB range and put it back into the AB range to re-light the burner. You would only do this if the burner blew out. The only indication was the fuel vapor streaming out of that engine, which you could only see by looking in the periscope.
Cruise Mach
‘Also, after reaching cruise Mach, I would recheck that the rudders were perfectly aligned with the airflow. We needed to ensure there was no trim drag to achieve the optimum range.
‘My primary job as pilot was keeping the pointy end going forward and doing everything to “make gas”. Running short of fuel is very anxiety-producing!’
*According to TheSR71Blackbird.com, if internal pressures inside the J58 intake become too great, the shock wave suddenly blows out the front of the inlet. During an intake unstart, the computer controlling the spike records the lack of pressure and responds by moving the spike forward to the subsonic flight position. Airflow immediately stops, thrust drops, and exhaust gas temperatures rise.
Check out Habubrats SR-71 X profile, SR71Habubrats Instagram profile, and Born into the Wilde Blue Yonder Habubrats Facebook page for further Blackbird photos and stories.
Photo by U.S. Air Force
