Exploring the Unknown: Selected Documents in ... - The Black Vault

Exploring the Unknown 357
The in-plane fly-around was conducted for 20 minutes starting at 7 hours
42 minutes g.e.t. The pilot conducted an out-of-plane fly- around for 11 minutes
starting at 8 hours 10 minutes g.e.t.
The command pilot, during the in-plane fly-around, allowed the range
between the two spacecraft to increase to an estimated 300 feet. The relative
position of spacecraft 6 at that time was above spacecraft 7, and slightly to the
rear. This distance appeared to be excessive for proper station keeping and the
range was quickly reduced to less than 100 feet. The radar system was not used
during the station-keeping per iod. These ranges were determined both by visual
observation in rela tion to the 10-foot diameter of the spacecraft as viewed through
the [7-27] optical sight during the flight and by measurements after the flight of
photographs taken with known optical systems.
It is recommended that station keeping not be conducted in-plane above
or below the target. The ideal condition for station keeping is SEF or BEF in
platform mode; however, station keeping can easily be conducted out-of-plane
at ranges up to 60 or 80 feet without losing the perceptive cues that pilots have
learned to recognize in formation fly ing with aircraft.
The smallest distance between spacecraft 6 and spacecraft 7 during
station keeping was approximately 1 foot, and both the command pilot and pilot
flew at this distance with great ease. This, of course, greatly enhanced the crew’s
confidence in the control system for subsequent station-keeping operations. The
control-system response can be described as perfect. The torque-to-inertia ratios
of the attitude control system using the pulse mode, and thrust-to-inertia ratios of
the translation system using minute inputs, were excellent for the station keeping
per formed during this mission. Docking with a target vehicle could have’ been
easily executed by applying a small burst of forward thrust from the l-foot range.
Document I-70
[CONFIDENTIAL] [DECLASSIFIED]
GEMINI VIII
TECHNICAL DEBRIEFING
March 21, 1966
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
MANNED SPACECRAFT CENTER
HOUSTON, TEXAS