Abstract: An apparatus for locking an aircraft door provided in the outer wall of an aircraft includes at least one locking shaft pin that locks the aircraft door in a fixed, closed position relative to the outer wall of the aircraft when the locking shaft pin is positioned or rotated into a locking position. The locking shaft pin is connected to a mechanical linkage forming a positioning arrangement. The positioning arrangement is coupled to a control element, which essentially includes a membrane connected to a control rod. The membrane is arranged within a housing so as to form an interior air chamber on one side of the membrane and an exterior air chamber on the other side of the membrane. The air pressure of the cabin interior is applied to the interior air chamber through an interior air pressure port, and the exterior ambient air pressure is applied to the exterior air chamber through an exterior air pressure port.

Abstract: An aircraft door is supported by at least two support rods. Each rod rests with one of its ends in a door hinge that is rotatable with the support rod through an angle of, for example 90.degree., while the door can be shifted up or down along the support rods. For this purpose a torque shaft which is rotatably mounted to the door frame is connected through toggle devices to the other end of the respective support rod, whereby rotation of the torque shaft lifts or lowers the door relative to the support rods. The same torque shaft is connected to the support rods through a linkage device, including a bellcrank lever for rotating the support rods simultaneously with the lifting or lowering of the door relative to the support rods, whereby the hinges can be moved from a recessed position inside the door structure when the door is closed into an extended position outside the door structure for opening the door.

Abstract: An operating mechanism for an aircraft door performs all the door motions and locking operations for the opening and closing of the door with the aid of electric motors which operate the respective elements of the mechanism through gear drives or through spindle drives to provide the power or torque moment for the respective motion. The motion sequence of the door operation is stored as a respective program in a memory of a central processing unit which in turn operates the electric motors in accordance with the programs. Operator initiated control signals are also provided to the central processing unit through respective panels. The pressurization and depressurization of the aircraft cabin is integrated into the door control so that pressurization cannot take place unless the doors are fully closed and locked and so that door opening cannot take place until depressurization is completed.

Abstract: An operating mechanism for an aircraft door performs all the door motions and locking motions for the opening and closing of the door with the aid of electric motors which operate the respective elements of the mechanism through gear drives or through spindle drives to provide the power or torque moment for the respective motion. The door sealing may be accomplished with contact hardware components or with toggle hardware components for taking up the forces resulting from the internal cabin pressure. The door is hinged to the aircraft body structure by a guiding and supporting hinging element, one end of which is hinged to the aircraft body structure while the other end is hinged to the door structure. The door swinging motions in the opening and closing directions, the door opening and closing motions and the door locking and unlocking motions are all performed by program controlled electric motors. Such motors also control the deployment of an emergency escape slide.

Abstract: The locking mechanism of an aircraft door is linked with a testing device in such a manner that the inoperability of the testing device indicates a failure in the proper locking or latching of the door in its closed position. The testing device may, for example, be a lever which is actuated last in a sequence of door closing and locking or latching steps. Such a lever could, for instance, be the lever for bringing an emergency chute into a ready or stand-by condition. The linkage assures that the testing lever for operating the emergency chute can be activated only if the door is properly closed and latched. As a result, a door that is incompletely closed and/or incompletely latched will provide an immediate indication of that situation.

Abstract: A fiber reinforced shell structure of synthetic material has an outer skin supported on a skeleton of longitudinal stringers interconnected by ribs. The stringers have a channel cross-section filled with a hard foam. The ribs have an approximately [ or I-shaped cross-section. The ribs are formed by an outer chord and by an inner chord interconnected by a web. If the structure is cylindrical, for example, the ribs extend circumferentially. The rib webs are made of rib web segments which are displaced relative to each other, for example in the circumferential direction in case of a cylindrical structure. The displacement of the web elements corresponds to the on-center spacing between neighboring longitudinal stringers, whereby the fiber reinforced material of the end portions of the rib web segments merge into rib reinforcing or bracing members, where the ribs intersect the stringers. The rib bracing members alternate in opposite directions along a rib and are filled with a hard foam.