A flight suit is a pair of white or blue coveralls that is worn primarily by the astronauts. Flight suits are nominally required for the astronauts during the Mission's "work times", in an effort to increase Mission Integrity, and to lend a professional feeling. Flight suits are optional for Mission Control, but they encourage mission integrity. They are decorated by mission patches and come in multiple sizes, though one size can usually fit all.
Once, it was required that all members purchase a flight suit for work session activities. It was so to protect the wearer's clothes from the unusually high amounts of dust and other dirtying substances that existed at the work session facilities. However, in recent years, especially after funding was cut off in 2001-02, the rules have relaxed and most members now use flight suits owned and left at Spacesim by alumni, though senior members, especially astronauts, often still purchase their own flight suits for various reasons, such as the accumulation of patches.
Many Spacesim members wear flight suits for the Week of Hype, as well as during many Lisgar events, to represent Spacesim. This was the case with the 2008 Spacesim Assembly as well as the Spacesim Dodgeball Team. It is also a tradition to wear them during Quickie Runs.
Flight Suits are not to be confused with EVA Suits, though during the 2007-08 Mission (Red Dawn), the flight suits, along with the "corsets" and tights/long underwear were used as the backup, emergency pressure suits.