The A-12’s first flight–unofficial and unannounced in keeping with a Lockheed tradition–took place on 25 (26?) April 1962 and almost caused the loss of the only OXCART aircraft built so far. Lockheed test pilot Lou Schalk flew the plane less than two miles, at an altitude of about 20 feet, because serious wobbling–Johnson described the movements as “lateral oscillations which were horrible to see”–caused by improper hookup of some navigational controls. Instead of circling around and landing, Schalk put it down in the lake bed beyond the end of the runway. When the A-12’s nose appeared out of a cloud of dust and dirt, Johnson’s angry voice erupted over the radio, “What in Hell, Lou?”

Pilot Lou Schalk recalls:

"It was determined that we would make a high-speed taxi test going down our 8000-foot concrete runway towards the Groom Lake bed which had probably 4-5 miles of lake bed suitable for landing beyond the end of the runway, so that seemed like a safe direction to go. The idea was that as I reached takeoff speed was to lift it off the ground and set it back down to see how it felt."

"Well, when we went down the runway and hit takeoff speed and lifted off, it was immediately out of control. It was oscillating longitudinally and laterally. It was obvious the airplane was very unstable. We did not have the damper systems on; no one ever turned the damper systems on on the first flight because you didn't trust them!"

"Finally I got hold of it, set it back down on the ground, and was probably a mile or so out on the lakebed at that point in time. Immediately disappeared into a cloud of dust. The tower called to see if I was all right. I replied 'I'm fine, I'm rolling out to slow down and turn around and taxi back.' The tower couldn't hear me becaue the antenna for my UHF transmitter was on the bottom of the fuselage and was blanked out for the direction of the tower's line of sight. So no one knew what was happening and in the dust kept waiting for the burst of flames as I ran into the mountains. After I turned the corner, if Kelly Johnson hadn't already had a heart attack, he probably breathed a sigh of relief. I taxied back in, and we talked about it that night...I said, 'Why don't we turn the dampers on before we try this again?' We all agreed that was a very good idea!"

"I still didn't know what had gone wrong, but I did know we had 12 to 15 thousand pounds of fuel on board for the taxi test. Flying an F-104, that's an awful lot of fuel, that's more that it carries, but we carried 76,000 pounds of fuel so we hardly had anything at all. It was all in the back end. The airplane was statically unstable, which meant that anytime you move the controls or if the airplane had any movement, you had to make a correctional movement with the controls to stop it, otherwise it would keep right on going; where if the airplane is stable, that means it will tend to return to its normal position, say if it hits some rough air or something like that. This is because of the center of gravity and its location to the center of pressure, which is usually about the midpoint of the wing."

"We had so much fuel in the back end of the airplane that the center of gravity was about 3 percent beyond the aft limit, and we were terrifically unstable. On the actual flight where we got airborne and stayed there, we were probably 3 percent forward of where our normal fuel loading would be. The reason that happened was that the ground crew and most of the people who were getting the airplane ready for this taxi test didn't know that we had decided to lift off the airplane and set it back down again that night except for Kelly, myself and the flight test engineer...no one told them!"

The next day, Schalk tried again, this time with the landing gear down, just in case. The flight lasted about 40 minutes. The takeoff was perfect, but after the A-12 got to about 300 feet it started shedding all the “pie slice” fillets of titanium on the left side of the aircraft and one fillet on the right. (On later aircraft, those pieces were paired with triangular inserts made of radar-absorbing composite material.) Technicians spent four days finding and reattaching the pieces. Nonetheless, the flight pleased Johnson. “We showed that the first flight troubles were not caused by basic aircraft [in]stability.”

Once the fillets were repaired, Article 121 was rolled out for its first official flight on 30 April, just under one year later than originally planned. A number of senior Air Force officers and CIA executives, including Deputy Director for Research Herbert Scoville and former project chief Bissell (who left the Agency in February 1962), witnessed the long-awaited event. Schalk again was the pilot. He took the aircraft up for 59 minutes and reached 30,000 feet and just under 400 mph; most of the flight was made at under 300 mph. He reported that the A-12 responded well and was extremely stable. Johnson said this was the smoothest official first flight of any aircraft he had designed or tested. On 4 May, with Schalk at the controls, Article 121 made its first supersonic flight, reaching Mach 1.1 at 40,000 feet. Problems were minimal. DCI John McCone, who had shown a keen interest in the OXCART program since becoming director in November 1961, sent Johnson a congratulatory telegram.