On April 25, 1962, Annie Jacobsen explains (in Area 51), the “Oxcart” was ready, and it was time for Lockheed test pilot Louis Schalk to suit up:
Two physiological support division officers helped Schalk into a flight suit, which looked like a coverall. There was no need for a pressure suit because today Schalk was only going to make a taxi test. Out on the tarmac, an engineer rolled up a metal set of stairs and Schalk climbed up into the strange-looking aircraft.
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Lou Schalk fired up the engines and began rolling down the runway for the taxi test. To everyone’s surprise, including Lou Schalk’s, the aircraft unexpectedly got lift. Given the enormous engine power, the aircraft suddenly started flying—lifting up just twenty feet off the ground. Stunned and horrified, Kelly Johnson watched from the control tower. “The aircraft began wobbling,” Johnson wrote in his notes, which “set up lateral oscillations which were horrible to see.” Johnson feared the airplane might crash before its first official flight. Schalk was equally surprised and decided not to try to circle around. Instead he set the plane down as quickly as he could. This meant landing in the dry lake bed, nearly two miles beyond where the runway ended. When it hit the earth, the aircraft sent up a huge cloud of dust, obscuring it from view. Schalk turned the plane around and drove back toward the control towers, still engulfed in a cloud of dust and dirt. When he got back, the Lockheed engineers ran up to the airplane on the metal rack of stairs. Kelly Johnson had only four words for Schalk: “What in Hell, Lou?” For about fifteen very tense minutes, Johnson had thought Lou Schalk had wrecked the CIA’s only Oxcart spy plane.
The following day, Schalk flew again, this time with Kelly Johnson’s blessings but still not as an official first flight. Harry Martin was standing on the tarmac when the aircraft took off. “It was beautiful. Remarkable. Just watching it took your breath away,” Martin recalls. “I remember thinking, This is cool. And then, all of a sudden, as Schalk rose up in the air, pieces of the airplane started to fall off!” The engineers standing next to Martin panicked. Harry Martin thought for sure the airplane was going to crash. But Lou Schalk kept flying. The pieces of the airplane were thin slices of the titanium fuselage, called fillets. Their sudden absence did not affect low-altitude flight. Schalk flew for forty minutes and returned to Area 51. It was mission accomplished for Schalk but not for the engineers. They spent the next four days roaming around Groom Lake attempting to locate and reattach the pieces of the plane. Still, it was a milestone for the CIA. Three years, ten months, and seven days had passed since Kelly Johnson first presented his plans for a Mach 3 spy plane to Richard Bissell, and here was the Oxcart, finally ready for its first official flight.
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Schalk traveled up to thirty thousand feet, flew around in the restricted airspace for fifty-nine minutes, and came back down. His top speed was four hundred miles per hour.