Aircraft door latch assembly

A flight deck door system for an aircraft, the flight deck door system comprising:

• a flight deck door, wherein the flight deck door, when in a closed position, separates a flight deck area of the aircraft from a cabin area of the aircraft;
• a door frame comprising a first post and a second post, wherein the flight deck door is rotatably coupled to the first post via a set of hinges such that the flight deck door is rotatable into the flight deck area in an open position;
• a latch recess positioned within the second post, wherein the latch recess is arranged to engage a door latch bolt of the flight deck door when the flight deck door is in the closed position;
• a driver positioned on an aft side of the flight deck door, wherein the driver is configured to retract the door latch bolt in response to a rotation of the driver to thereby transition the flight deck door from a locked state to an unlocked state, and wherein the driver includes an aperture;
• and
• a door latch assembly comprising:
• a locking pin movable from an extended position in which the locking pin is positioned in the aperture of the driver to thereby inhibit rotation of the driver such that the flight deck door is maintained in the locked state, to a retracted position in which the locking pin is configured to be removed from the aperture of the driver to thereby enable rotation of the driver to transition the flight deck door from the locked state to the unlocked state;
• a solenoid including a solenoid plunger having a first end coupled to the locking pin and a second end coupled to a shaft, wherein when the solenoid is not actuated the solenoid plunger is biased by a spring to move the locking pin into the aperture;
• a lever arm having a first end engaging the shaft;
• and
• a switch including an actuator button in contact with the lever arm,
• wherein when the solenoid is actuated the solenoid plunger moves to retract the locking pin from the aperture and causes the shaft to displace the lever arm and the actuator button to activate the switch.

A method for establishing a flight deck door of an aircraft, wherein the flight deck door, when in a closed position, separates a flight deck area of the aircraft from a cabin area of the aircraft, the method comprising:

• positioning a door frame in the cabin area, wherein the door frame comprises a first post and a second post, and wherein the second post comprises a latch recess;
• coupling the door frame to the aircraft;
• and
• coupling the flight deck door to the first post via a set of hinges, wherein the flight deck door is rotatable via the set of hinges into the flight deck area to an open position;
• positioning a driver on an aft side of the flight deck door, wherein the driver is configured to retract a door latch bolt in response to a rotation of the driver to thereby transition the flight deck door from a locked state to an unlocked state, and wherein the driver includes an aperture;
• and
• positioning a door latch assembly in the flight deck door, wherein the door latch assembly comprises:
• a locking pin movable from an extended position in which the locking pin is positioned in the aperture of the driver to thereby inhibit rotation of the driver such that the flight deck door is maintained in the locked state, to a retracted position in which the locking pin is configured to be removed from the aperture of the driver to thereby enable rotation of the driver to transition the flight deck door from the locked state to the unlocked state;
• a solenoid including a solenoid plunger having a first end coupled to the locking pin and a second end coupled to a shaft, wherein when the solenoid is not actuated the solenoid plunger is biased by a spring to move the locking pin into the aperture;
• a lever arm having a first end engaging the shaft;
• and
• a switch including an actuator button in contact with the lever arm,
• wherein when the solenoid is actuated the solenoid plunger moves to retract the locking pin from the aperture and causes the shaft to displace the lever arm and the actuator button to activate the switch.