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Home Up Flight Information X-15 Flight Request Operations Flight Report Planned Flight Path Radio Transcript
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The Crash of the X-15A-3
15 November 1967
As had happened in some other research aircraft
programs, a fatal accident signaled the end of the X-15 program. On 15
November 1967 at 10:30 a.m., the X-15-3 dropped away from its B-52
mothership at 45,000 feet near Delamar Dry Lake. At the controls was
veteran Air Force test pilot, Major Michael J. Adams. Starting his climb
under full power, 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. In the Dryden Flight
Research Center (DFRC) flight
control room, fellow pilot and 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. When he concluded the
wing-rocking portion of the climb, the X-15 began a slow, gradual drift
in heading; 40 seconds later, when the craft reached its maximum
altitude, it was off heading by 15°. As the plane came over the top,
the drift briefly halted, with the plane yawed 15° to the right. Then
the drift began again; within 30 seconds, the plane was descending at
right angles to the flight path. At 230,000 feet, encountering rapidly
increasing dynamic pressures, the X-15 entered a Mach 5 spin.
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Above is the X-15A-3 on its way to a test flight.
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The X-15A-3 just after being dropped from the B-52.
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Major Adams in the cockpit of an X-15A at Edwards AFB
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Major Michael J. Adams in front of the X-15A
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In the flight control room
there was no way to monitor heading, so nobody suspected the true
situation that Adams now faced. The controllers did not know that the
plane was yawing, eventually turning completely around. In fact, control
advised the pilot that he was ”a little bit high,” but in ”real
good shape.” Just 15 seconds later, Adams radioed that the plane
”seems squirrelly.” 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. The chase pilots, realizing that the
X-15 would never make Rogers Lake, went into afterburner and raced for
the emergency lakes, for Ballarat, for Cuddeback. 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.
Adams was in a relatively high altitude dive and had a good chance of
rolling upright, pulling out, and setting up a landing. But now 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. All the while, the plane shot downward at
160,000 feet per minute, dynamic pressure increasing intolerably. High
over the desert, it passed abeam of Cuddeback Lake, over the Searles
Valley, over the Pinnacles, narrowing on toward Johannesburg. As the
X-15 neared 65,000 feet, it was speeding downward at Mach 3.93 and
experiencing over 15 g vertically, both positive and negative, 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. On the
ground, NASA control lost all telemetry at the moment of breakup, but
still called to Adams. A chase pilot spotted dust on Cuddeback, but it
was not the X-15. Then an Air Force pilot, who had been up on a delayed
chase mission and had tagged along on the X-15 flight to see if he could
fill in for an errant chase plane, spotted the main wreckage northwest
of Cuddeback. Mike Adams was dead and the X-15 destroyed.
Afterwards, Michael Adams was laid to rest at the Memorial Park
Cemetery in Monroe, Ouachita Parish, Louisiana.
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An aerial view of the crash.
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The remains of X-15-3 lies on the desert floor.
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[ Flight Information ] [ X-15 Flight Request ] [ Operations Flight Report ] [ Planned Flight Path ] [ Radio Transcript ]
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Very little remains at this site.
In fact, aside from a small American flag posted in the center of the
site, the average person would been totally unaware of the historic
nature of their surroundings. Small, scattered pieces are
sprinkled there, and finding anything of the aircraft at the site is
nearly impossible (however, portions of the X-15A-3 such as an engine
access panel, a reaction control rocket for maneuvering in the upper
atmosphere, a piece of the horizontal stabilizer, and a section of
vertical stabilizer that had the numerals '72' on it, were found as late
as 1992). Rumor has it that the left wing has never been found
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Here is another photo of the site where the main fuselage
came to rest. In the background you can see the
same cleft on the hill as in the crash photo.
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Unlike most other crash sites, there is virtually
nothing to be found of the aircraft laying on the surface.
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Click here
to own a piece of X-15A
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