The pilot sat on the left side in the cockpit above the wireless operator. The flight engineer filled in as a co-pilot, seated on a folding seat to the right of the pilot, during crucial manoeuvres such as take-off. Aft of the pilot and on the same level as the navigator and wireless operator was the flight engineer's compartment. Another compartment aft of the flight engineer contained two bunks originally intended for resting crew members, but almost always used for treating and berthing injured crew. This area led to the two-gun dorsal turret. The tail gunner occupied a four-gun turret at the extreme aft end of the aircraft.