Landing the STS-120 Space Shuttle: three hours before touchdown
About three hours before touchdown today (approx 10 a.m.) the payload doors of the orbiter are closed and then Mission Control gives the “go” for Ops 3, which is the portion of the Shuttle’s flight control software that manages entry and landing.
“Landing preparations aboard space shuttle Discovery got under way this morning at about 8 a.m., and the crew closed Discovery’s 60-foot payload bay doors at about 9:15 a.m.”
“Crew members have transitioned the onboard computers to the software package used for landing, and climbed into their orange launch-and-entry suits. During this time, the astronauts also begin to drink large quantities of fluid to help their bodies readjust to Earth’s gravity after landing.”