System Testing of Communications and Tracking Links for First Orbital Flight of the Space Transportation System (STS)

Abstract

Verification testing of the communications and tracking (C&T) links prior to the first STS flight has been a prime concern. The C&T system for the Space Shuttle orbiter (SSO) provides for the transmission and reception of voice, command data, tracking data, telemetry, television, main engine data, external tank (ET) data, and payload data between the flight vehicle and the ground (communication between detached payloads and ground is achieved via the SSO as bent-pipe data or as part of the standard pulse code modulation telemetry data), and for the transmission and reception of voice and/or data between the flight vehicle and extravehicular activity (EVA). The C&T links will be operated during preflight, in-flight, and postflight phases of the orbital flight test (OFT) program. The verification testing program for C&T links makes use of the results obtained from element-level component and subsystem tests and analyses, and adds this information to the data from a series of combined-element analyses and system-level tests to ensure that performance requirements are met. A verification network outlines major paths leading toward integrated verification of the C&T links for OFT. A matrix illustrates the STS C&T system verification requirements versus the testing facilities and identifies STS RF links test at various facilities. Another matrix shows the verification requirements, methods and criteria, and hardware and software requirements of all facilities for each RF link. The role of each facility in the verification process is described. Special tests that have supported overall readiness are listed.