bomb bay 
noun
A compartment in the fuselage of an aircraft in which bombs are held and from which they may be dropped.The largest piece of the aircraft is the bomb bay, still painted in its undercoat pink colour, and the area just to the rear of the bay....
- Sergeant Berends left the flight deck for the bomb bay where he began transferring fuel from the dead engines to the straining right engines.
- Kline was catapulted forward 20 feet across the disintegrating bomb bay into the bulkhead of the command deck.