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Royston, C. L., Jr.

Publications and source records attributed to Royston, C. L., Jr..

Apollo experience report: Communications system flight evaluation and verification

Flight tests of the synergetic operation of the spacecraft and earth based communications equipment were accomplished during Apollo missions AS-202 through Apollo 12. The primary goals of these tests were to verify that the communications system would adequately support lunar landing missions and to establish the inflight communications system performance characteristics. To attain these goals, a communications system flight verification and evaluation team was established. The concept of the team operations, the evolution of the evaluation processes, synopses of the team activities associated with each mission, and major conclusions and recommendations resulting from the performance evaluation are represented.

Travis, D.

Postflight analysis of the EVCS-LM communications link for the Apollo 15 mission

Data from the Apollo 15 mission were used to compare the actual performance of the EVCS to LM communications link with the preflight performance predictions. Based on the results of the analysis, the following conclusions were made: (1) The radio transmission loss data show good correlation with predictions during periods when the radio line of sight was obscured. (2) The technique of predicting shadow losses due to obstacles in the radio line of sight provides a good estimate of the actual shadowing loss. (3) When the transmitter was on an upslope, the radio transmission loss approached the free space loss values as the line of sight to the LM was regained.

Royston, C. L., Jr.