He completed training as a backup commander of the Mir-15 crew from July 1993 to January 1994.

Schweickart instead served as backup commander for the first Skylab space station mission, which flew during the spring of 1973.

Neil Armstrong got this honor by virtue of being Borman's backup commander.

Jim Lovell, the backup commander, mentioned the idea of eagles, a symbol of the United States.

It was a rump session--hastily organized by delegates able to move again after an hour, or by their backup commanders from a number of starships.

After Apollo 12, Gordon was assigned as backup commander of Apollo 15.

Zayikin was assigned as backup commander for Voskhod 2.

Schweickart also served as the backup commander for the Skylab 2 crew in 1973.

He served as backup commander for Mir EO-7.

Since then he joined the ISS advanced training as a backup commander and, from 2009, as a flight engineer.