Mid-deck (“Habitation Compartment” or BO)

For ascent and return the mid-deck could have seats installed for up to six crew members. In orbit it served as the living and sleeping quarters for the crew, containing (among other things) lockers for stowage, sleeping bags, a galley with a small reclining table, washing facilities, and a toilet. In the aft of the mid-deck there was room for an internal airlock to conduct spacewalks during non-docking missions. For docking missions Buran would have carried a combined docking system/airlock installed in the cargo bay just behind the crew compartment.

The mid-deck also housed three small equipment bays with radio equipment and thermal control systems that could be accessed by the crew via panels. There was a

hatch on the port side of the mid-deck for normal crew ingress and egress, which could be opened very quickly by the crew in emergency situations. As on the Orbiter, there was a small porthole in the middle of the side hatch. Access to the flight deck was via two interdeck openings (left and right), although only the left one was supposed to be used in flight. The mid-deck had its own instrument panel (17M212) with among other things an on-board clock and an emergency warning system. There were also separate instrument panels for the airlock (17M213) and the docking adapter (17M214).