A privacy door assembly for installation in an aircraft relative to a flight deck door of the aircraft includes a door frame having a first post and a second post, where the second post comprises a latch recess. The privacy door comprises a latch positioned on an edge of the privacy door and arranged to engage the latch recess when the privacy door is in a closed position within the door frame. An access door is positioned in the privacy door, where the access door is rotatable from a closed position to an open position in a forward direction. A first mechanical door handle system including a mechanical combination lock is positioned on an aft side of the privacy door and coupled to the latch, and a second mechanical door handle system is positioned on a forward side of the privacy door and coupled to the latch.