Apollo 17 0.1 Prelaunch part 3

[edit] Spacecraft

Spacecraft operations got under way in March 1972. During the next four months John Williams's directorate conducted the normal sequence of tests. Spacecraft engineers ran into some typical problems. In May Grumman engineers determined that the rendezvous radar assembly had received too much voltage during the tracking and pointing test at the boresight range. A new radar was installed on the 24th. A month later the landing radar began locking up intermittently and it was replaced. The lunar rover required several changes including replacement of forward and aft steering motors.

The biggest change in command-service module operations concerned the scientific instrument module, which gained three new experiments: a lunar sounder, an infrared scanning radiometer, and a far ultraviolet spectrometer. The sounder was essentially a radar that could determine the physical properties of the lunar crust to a depth of 1.5 kilometers. This data, coupled with information gathered from cameras, the laser altimeter, and surface measurements, would allow the construction of a detailed topographical profile of the moon. The radiometer provided data from which scientists could prepare an accurate thermal map of the lunar surface. The new spectrometer measured compositional and density variations of the lunar atmosphere.

Optical Recorder of the Lunar Sounder Experiment (S-209) which will be mounted in the SIM bay of the Apollo 17 Service Module. The Lunar Sounder will probe three-quarters of a mile below the Moon's surface from the orbiting Apollo 17 spacecraft. Electronic data recorded on film will be retrieved by the crew during transearth EVA.

Image:S72-53472.jpg Artist's concept of how radar beams of the Apollo 17 Lunar Sounder experiment will probe three-quarters of a mile below the Moon's surface from the orbiting spacecraft. The Lunar Sounder will be mounted in the SIM bay of the Apollo 17 Service Module.

The Infrared Scanning Radiometer (ISR), Experiment S-171, which will be mounted in the SIM bay of the Apollo 17 Service Module. The ISR experiment will provide a lunar surface temperature map with improved temperature and spatial resolution over what has been possible before.

Far-Ultraviolet Spectrometer, Experiment S-169, one of the lunar orbital science experiments which will be mounted in the SIM bay of the Apollo 17 Service Module. Atomic composition, density and scale height for several contituents of the lunar atmosphere will be measured by the experiment. Solar far-UV radiation reflected from the lunar surface as well as UV radiation emitted by galactic sources also will be detected.

The new experiments, particularly the lunar sounder, caused considerable headaches. For testing the sounder, the lunar surface had to be simulated. The sounder recorded the returning signals with an advanced optical recorder that required a special data reduction machine. After the launch team completed a lunar sounder test, the results were sent to the University of Kansas for interpretation. As the head of the Experiments Section recalled, "It would take weeks sometimes to get the results back and they might come back and say, 'You have nothing on the tapes."' North American had trouble integrating the new experiments with the service module hardware.