Gemini Reentry Control System (RCS) thruster, or Thrust Chamber Assembly (TCA).
Flown as part of the Gemini IX spacecraft June 3-6, 1966.
One of 16 RCS thrusters in the nose section for spacecraft attitude control during reentry, and one of four removed for study.
Mounted in position 6A (pitch up on the right side of the forward ring of thrusters).
Enhanced NASA photo taken by Gene Cernan during his spacewalk shows the artifact in flight.
Eight similar thrusters were also used in the Gemini Equipment Adapter section for the Orbital Attitude and Maneuvering System (OAMS).
Rated thrust 25 pounds.
Manufactured by Rocketdyne as Model SE-6.
Charring on the thruster nozzle resulted from the heat of combustion as well as reentry heating.
Autographed by astronauts Tom Stafford, Gemini-Titan (GT)-IX Commad Pilot, and Gene Cernan, GT-IX Pilot.
Fuel injector (similar to the oxidizer injector shown) was removed by NASA to determine if preflight off-specification measurements would affect performance. The valve was found to be in excellent condition and the measurements acceptable for thrusters produced for later flights.
See NASA photo of the artifact before its removal, and compared with its appearance now.
Compare the Gemini thruster with the thrusters used in Mercury and Apollo (in photo below).
”RCS” Note: For most spacecraft, the system for controlling attitude in space is called the Reaction Control System, or RCS. (Thrusters create an action to produce a spacecraft reaction.)
In Gemini, this system was called the Orbital Attitude and Maneuvering System (OAMS). The system used during Gemini reentry (after the adapter section with the OAMS had been discarded) was
called the Reentry Control System, also abbreviated RCS.
2.1 lbs. (0.95 kg)
Above, NASA photo of Gemini IX spacecraft taken by astronaut Cernan during his spacewalk. Nose with radar and parachute canisters is at lower right, open hatch at upper
center. This thruster artifact is indicated by the yellow arrow.
Autographs of astronauts Tom Stafford, Gemini-Titan 9 (GT-9) Command Pilot (Commander) and Gene Cernan, GT-IX Pilot.
Above, NASA photo of the Reentry Control System (RCS) during Gemini IX postflight inspection showing thrusters 6 and 7 of Ring A (right) and Ring B. This artifact is Thrust
Chamber Assembly (TCA) number 6A, at upper right in the photo. This and three other TCAs (3A, 4B, and 8B) were removed for examination. The TCA shipping record confirms that the serial number matches
this artifact. Below, detail of the recovered TCA compared with the artifact today.