On one occasion our squadron commander was walking around with a black cloud above him. All our aircraft on the station were u/s except one and he was supposed to provide an ACP aircraft plus a spare. I suggested that he nominate a u/s aircraft as the prime and the serviceable one as the backup. i.e. Jump in, it's u/s; go to the backup.
Cunning plans like that could have got you the nickname of Baldrick
