Dave Scott’s Portable Life Support System (PLSS) and Remote Control Unit (RCU) electrical dust cover used on the surface of the moon during the three Extra Vehicular Activities (EVA) of the Apollo 15 mission. This dust cover or cap protected the PLSS-RCU connector from contamination due to lunar dust accumulated during each EVA on the lunar surface. The aluminum cover measures 1.5″ in diameter, with the top featuring a .5″ black-and-silver stripe indicator and a central nipple steel bolt; the edge is ridged in a diamond pattern for grip and has been marked by hand with several serial numbers, some only partially legible: “N/O A…S/N 9A 010…SV 723763.” This PLSS dust cover was a vital element in the protection of the electrical connection between the PLSS and the RCU, which was mounted on the astronaut’s chest and used to monitor the condition and operations of the PLSS. Of particular concern was the pervasive dust that accumulated on the spacesuit and PLSS during the EVAs. Prior to donning the suit, the dust cover was removed and temporarily stored in the onboard ‘purse’ for retrieval and replacement after each EVA. After the dust cover was removed, the RCU cable was attached after the spacesuit was donned. Upon reentering the lunar module after an EVA the RCU was disconnected and the dust cover was placed over the PLSS connector to protect from dust contamination and potential malfunction of the connection between the PLSS and the RCU. In fine condition. Accompanied by a signed letter of provenance from Scott, in part: “I hereby certify that the Apollo 15 PLSS-RCU Electrical Connector Dust Cover (#2) included with this letter was an integral part of the PLSS that Used during the three periods of Extra Vehicular Activity…on the surface of the Moon during the first extended scientific exploration of the Moon, July 26-August 7, 1971…This PLSS-RCU Connector Dust Cover (#2) has been in my personal collection since returning to Earth." A decidedly uncommon piece of hardware that was used extensively during the EVA operations of Apollo 15, the first extended scientific exploration of the Moon. From the personal collection of Dave Scott.
Terms and abbreviations used in our descriptions.