scope:

Description of Driving Event:

At the Loral Vought Systems in Dallas, Texas prior logbook test data history was evaluated as part of a normal failure investigation. During this review a trend in data was sometimes observed that indicated a prior drift or shift towards an out-of-tolerance condition.

The Scout Program initiated a test data monitoring program on selected assemblies. Design, quality and/or reliability engineers reviewed the test data after each retest on the assembly or vehicle level. The appropriate engineer maintained supplementary notes. The list of assemblies to be monitored grew as additional parameters were identified.

Typical parameters monitored were:

A. Spin-up time, mass unbalance and null voltages on gyros

B. Receiver and transmitter frequencies on beacon transponders

C. Output frequencies of voltage controlled oscillators

D. Resistance measurements on relay assemblies

E. Discharge times at constant current on rechargeable batteries

F. De-spin time on bearings

This practice has been in place since the beginning of the Scout Program in 1960.