The original prime crew for Mercury Atlas-7 was Deke Slayton, however Slayton was removed from all flight crew availability after the discovery of cardiac arrhythmia during a training run in the "g"-loading centrifuge.
The original prime crew for Mercury Atlas-7 was to have been Deke Slayton, with Schirra as his back-up. However Slayton was removed from all flight crew availability after the discovery of cardiac arrhythmia during a training run in the "g"-loading centrifuge.