Close-out is the process that is completed in preparing an aircraft or spacecraft and its crew for flight.
The seven members of the Space Shuttle close-out crew help astronauts strap in and take care of any other last-minute needs that arise. The crew is also responsible for closing and sealing the crew access hatch and are the last non-crew members that astronauts see before returning from the mission. The Shuttle close-out crew consists of elite technicians, an active astronaut who is not assigned to that mission and a NASA quality inspector.[1]