Communications Carrier Electronic Module (CCEM), the hardware portion of the
Communications Carrier Assembly (CCA) (headset) worn by Apollo astronauts throughout their flights. (A lightweight headset was also available for use when the space suit was not required.)
The CCA is commonly known as the “Snoopy cap” for its resemblance to the hat
worn by the dog Snoopy in the Charlie Brown cartoon strip.
Downgraded to Class III and utilized for astronaut training after the mission.
Manufactured by David Clark Co. with earphone and microphone modules made by Pacific
David Clark Skylab Final Report indicates that the internal modules of the Apollo 17 headsets were re-encapsulated. This
explains the appearance of the cuts and sealant. X-ray images show that only the microphone modules were disturbed.
The 16647G-01 Harness Assembly, Electrical is a part of the overall CCA part number 16536G-04 (David Clark Final Skylab Report, with -04 and -07 applying to the Skylab parts).
The part number of the CCEM, 16495G-02 is seen in photos below to be associated with the 16647G-01 Harness Assembly,
CSD/GFE Allocations and Schedules by Vehicle for Apollo 17, Final Report, December 15, 1972, lists S/N 270 as one of the
CCAs for the mission.
Altitude Chamber runs conducted on October 13, 1972 using flight hardware identify the
S/N 270 CCA as Cernan’s.
Markings on the unit indicate reduction to Class III, and faded “WIF,” for
“Water Immersion Facility,” the water-filled pool used before 1981 for astronaut weightlessness training.
Obtained as surplus from NASA.
1.33 lbs. (0.60 kg)
Above, X-ray view of the right side of an undisturbed Apollo CCEM (headset). The earphone module can be seen at top, with the microphone module visible at the center. The microphone boom trails off to the center left. The umbilical mounts at the lower left, with leads curving to the right behind the earcup. (Many thanks to the friendly staff at A-Lab Corp. in Dayton, Ohio for their digital non-destructive testing services.)
Above, X-ray view of the right side of Cernan’s
Apollo CCEM (headset). Compared with the reference CCEM, the modules appear to be identical. The earphone module is undisturbed, while the microphone module has been removed and re-inserted.
Wires leading to it have been soldered. The connection inside the microphone boom appears to be broken.
Above, X-ray view of the left side of an undisturbed Apollo
CCEM (headset) showing the earphone module at top and microphone module at right.
Above, X-ray view of the left side of Cernan’s Apollo
CCEM (headset). Similar to the right side, the earphone module is undisturbed, while the microphone module has been removed and re-inserted. Wires leading to it have been soldered. Compared
with the reference CCEM, and even compared with the right side, the microphone module here appears somewhat different. For example, note the different arrangement of the two large cylindrical
components, and no visible row of small square features. It is not known if the original microphone module had been modified before re-encapsulation, or if possibly a different module has
been inserted, perhaps to test a Skylab modification.
In the above NASA photo, Apollo 17 astronaut Gene Cernan,
wearing this headset, rests inside the Lunar Module after the second lunar EVA of the mission, December 12, 1972.