Mounted on the chest of the EMU, the system provided simple controls for communications and some EMU functions, as well as warnings and indicators for EMU status. It had a secondary function as a mounting for the standard Apollo Hasselblad camera and Oxygen Purge System actuator.
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View from left rear |
Dimensions |
Main controls |
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Oxygen Quantity |
Major Features |
James Lovell |
Looking at the top of the RCU (from the rear, as the crewmen did when it was mounted on the EMU), the features are as follows, from left to right:
On the right side of the unit (again looking from the rear) was mounted the OPS actuator, used to supply emergency oxygen in case of a suit failure
The left side was featureless, except for a bar and strap used to operate the clamps that attached the unit to the EMU.
On the front face of the unit, (as seen standing in front of the crewman) was the Hasselblad camera mount, and the crewman's name tag (in red for the Commander, and in black for the Lunar Module Pilot).
On the rear face was a set of clamps used to attach the RCU to the suit. Two upper clamps attached to the PLSS shoulder straps, and a 3rd one attached to a bracket on the fornt of the EMU. A small strap was included to operate the clamps with the bulky lunar gloves on.
Photos by Ulli Lotzmann
Used with permission.
This is a training unit, now in the Smithsonian Institution's Garber Facility
where Ulli photographed it in 2006 with the invaluable aid of Amanda Young.
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Beautiful photo of
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Rear face, showing clamps
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Top face of the unit |
Bottom |
Left side/back |
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Left side/bottom |
Right side - OPS Actuator
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Front face - the strap used
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Side view of plug |
End view of the plug. |
Photos by Paul Kashuk
Used with permission.
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Front face. Note
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Top view |
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Left side. Note strap
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Right side - Note
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References
2. Portion of Figure 2-43, pages 2-104 in "Apollo Operations Handbook, Extravehicular Mobility Unit, Vol. 1, System Description, CSD-A-789-(1), Apollo 15-17 Rev. V, March 1971."
3. Figure 2.11.5, page 2.11-8 in "Apollo Operations Handbook, Lunar Module, LM-10 and Subsequent, Vol. 1, Systems Data, NAS 9-1100, 1 April 1971."
4. A portion of Figure 2-43, pages 2-103 in
"Apollo Operations Handbook, Extravehicular Mobility Unit, Vol. 1,
System Description, CSD-A-789-(1), Apollo 15-17 Rev. V, March 1971."
6. This is believed to be a Hamilton-Standard illustration.
6. NASA Photo 70-HC-74.