Gemini VI-A
proved that rendezvous in
space with another vehicle was possible. Docking, or the joining of two
spacecraft in orbit, was still an elusive goal.
The intended docking target for the Gemini program
was the
Agena. The Atlas Agena launch vehicle had exhibited terrible
reliability. Its failure before the originally planned Gemini VI
mission cost Schirra and Stafford their docking opportunity.
Gemini VIII was the next mission that would attempt
docking. This could occur only if the Agena could attain orbit.
The Gemini VIII commander was Neil Alden Armstrong.
He
was a veteran test pilot with experience flying the X-15 rocket
plane. Armstrong's pilot on Gemini VIII would be David Randolph
Scott.
On March 16, 1966, at 11:00 AM Eastern Standard
Time, an
Atlas with the Agena
docking
target for Armstrong and Scott lifted off. Unlike it predecessor,
this Agena reached a successful orbit. Forty one minutes later, Gemini
Titan VIII lifted off to pursue its target.
The rendezvous phase of the mission went very
well.
Armstrong and Scott had caught up with the Agena and flew in tandem
with it. While Armstrong performed this station keeping exercise,
Scott inspected the Agena. They had to make sure there were no
dangerous issues with the Agena before docking with it.
No problems were seen and Armstrong was given the go
ahead
for docking. At a rate of about 3 inches per second, Armstrong nosed
his Gemini spacecraft into the docking adapter on the Agena.
Armstrong called down to mission control, "Flight, we are
docked! It's
... really a
smoothie - no noticeable oscillations at all."
The Agena vehicle had its
own propulsion and attitude control systems. These systems could
be controlled both from the ground and from the crew on the Gemini
spacecraft. Armstrong and Scott began to put the Agena through its
paces.
Suddenly the crew realized they had serious problems. Instead of
being in level flight, their attitude indicator told them they were now
in a 30 degree roll. With the Gemini's attitude control system,
Armstrong struggled to stop the rolling motion of the vehicles.
Armstrong stopped the motion briefly, but then it began
again.
Not only that, but they began to roll faster and faster.
Frantically the crew flipped switches on and off hoping to isolate the
problem. Nothing seemed to work.
The crew noticed that their attitude control system fuel had dropped to
30 percent. This might indicate that the problem lay with the
Gemini spacecraft and not with the Agena.
The decision was made to undock from the Agena. Armstrong once again
steadied the two craft. Scott hit the undocking button and they
backed away from the Agena.
Armstrong radioed, "We have serious
problems here. We're
tumbling end-over-end up here. We're disengaged from the Agena."
That was when their problems really began. Gemini VIIII was now
spinning at a dizzying rate of nearly one revolution per second. The
rate was so fast that the crew had difficulty reading the instruments
on their control panel. Nearing the point of blackout, Armstrong
made the decision to shut off the orbital attitude control system and
switch on the reentry attitude control system.
At first nothing seemed to happen, but slowly the motion of the Gemini
spacecraft was stopped. Armstrong and Scott then proceeded to
isolate what had caused their problems in the first place. By
methodically reactivating the orbital maneuvering system, they were
able to determine that thruster number 8 was stuck on. This was
the source of their gyrations.
Although the crew was now in a stable flight configuration, their
mission had come to an end. Mission rules dictated once the
reentry control system has been activated, the spacecraft return to
Earth as soon as possible. There was no backup to the reentry control
system. If a problem developed with the reentry system, the crew might
become stranded in orbit.
Gemini VIII
made an
emergency landing in the Pacific Ocean. This
emergency landing at a contingency site meant that the recovery
ships were not in the optimum position. Three hours after
splashdown, the crew was on board the recovery vessel. The ship
was a
United States Navy destroyer named the USS Leonard F. Mason.
Mission duration for Gemini VIII was 10 hours, 41 minutes and 16
seconds. The mission accomplished the first docking in
space. Many mission objectives were lost however due to the
abbreviation of the flight. Thankfully another brush with
disaster in space was averted by the actions of a well trained crew.
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