Editing STS-4 (section)

=== Backup crew ===
From STS-4 onwards, NASA halted the appointment and training of complete backup flight crews. Instead, individual flight crew members were assigned backups who could take their place within the prime crew. The decision on whether to appoint a reserve crew member was made on a per-flight basis by flight management teams at [[Johnson Space Center]]. Consequently, the last NASA flight to have a full-time backup crew was [[STS-3]].