I remember Steve Austin as the Six Million Dollar Man growing up. But it didn’t always go by the script.
This wreckage is from the November 1967 crash of the X-15A-3 rocket plane that killed pilot Michael Adams and ended the X-15 program. It still bears pencil marks on its inner face from the construction. And it has rows of flat-head screws.
Fellow pilot Bill Dana signed the face in silver ink. Dana flew this particular X-15 sixteen times prior, and became Chief of NASA’s Dryden Flight Research Center (DFRC) in Edwards, California.
This artifact is a counterpoint in the collection to the highlight of the X-15 program, the fastest windshield on Earth, which Pete Knight flew to Mach 6.7 a month earlier.
A description of that fateful day:
At 10:30 a.m., the X-15-3 dropped away from its B-52 mother ship at 45,000 feet near Delamar Dry Lake. At the controls was veteran Air Force test pilot, Major Michael Adams. Starting his climb under full rocket thrust, he was soon passing through 85,000 feet. Then an electrical disturbance distracted him and slightly degraded the control of the aircraft. Having adequate backup controls, Adams continued on. At 10:33 he reached a peak altitude of 266,000 feet (becoming America’s 27th astronaut). In the DFRC flight control room, mission controller Pete Knight monitored the mission with a team of engineers. Something was amiss. As the X-15 climbed, Adams started a planned wing-rocking maneuver so an on-board camera could scan the horizon. The wing rocking quickly became excessive, by a factor of two or three. At 230,000 feet, encountering rapidly increasing dynamic pressures, the X-15 entered a Mach 5 spin.
At 10:34 came a shattering call: ”I’m in a spin, Pete.” A mission monitor called out that Adams had, indeed, lost control of the plane. A NASA test pilot said quietly, ”That boy’s in trouble.” Plagued by lack of heading information, the control room staff saw only large and very slow pitching and rolling motions. One reaction was ”disbelief; the feeling that possibly he was overstating the case.” But Adams again called out, ”I’m in a spin.” As best they could, the ground controllers sought to get the X-15 straightened out. They knew they had only seconds left. There was no recommended spin recovery technique for the plane, and engineers knew nothing about the X-15’s supersonic spin tendencies.
Adams held the X-15’s controls against the spin, using both the aerodynamic control surfaces and the reaction controls. Through some combination of pilot technique and basic aerodynamic stability, the plane recovered from the spin at 118,000 feet and went into a Mach 4.7 dive, inverted, at a dive angle between 40 and 45 degrees.
But then came a technical problem that spelled the end. The Honeywell adaptive flight control system began a limit-cycle oscillation just as the plane came out of the spin, preventing the system’s gain changer from reducing pitch as dynamic pressure increased. The X-15 began a rapid pitching motion of increasing severity, with dynamic pressure increasing intolerably
As the X-15 neared 65,000 feet, it was speeding downward at Mach 3.93 and experiencing over 15 g vertically and 8 g laterally. It broke up into many pieces amid loud sonic rumblings, striking northeast of Johannesburg. Two hunters heard the noise and saw the forward fuselage, the largest section, tumbling over a hill.
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