To keep your pilots alive forever, make a copy of the PILOTS.DAT file
 before going on a dangerous mission. If you get killed, you can copy
 the file back and you pilot is resurrected as though he had nver
 flown the fatal mission. 
 
 For example, to copy the file, change to the Aces directory and type:
 
 COPY PILOTS.DAT BACKUP.XXX
 
 To resurrect the pilot, change to the Aces directory and then type:
 
 COPY BACKUP.XXX PILOTS.DAT
 
 Make sure you copy the PILOTS.DAT file every time you successfully
 complete a mission.