Translatable outward opening plug-type aircraft door and actuating mechanisms therefor

An outward opening plug-type aircraft door of the type adapted to be mounted in an ingress/egress cutout opening formed in the aircraft fuselage and bounded by generally vertical fore and aft fuselage frame members, said door comprising, in combination:

• (a) means defining a generally L-shaped hinge element having a relatively short hinge arm and a relatively long hinge arm;
• (b) means for securing said relatively short hinge arm to one of the generally vertical fore and aft frame members bounding in the ingress/egress cutout opening in the aircraft fuselage with freedom for rotation about a first generally vertical hinge axis;
• (c) an outwardly opening plug-type aircraft door dimensioned to be received in and to close the ingress/egress cutout opening in the aircraft fuselage, said door being mounted in cantilever fashion on the free extremity of said relatively long hinge arm for rotation about a second generally vertical hinge axis;
• and,
• (d) means defining a programming mechanism interconnecting said aircraft door, said hinge element and said one of the generally vertical fore and aft frame members for controlling the rotational attitude of said aircraft door as the latter is shifted between fully closed and fully opened positions and for maintaining said aircraft door in a plane essentially parallel to the plane containing the ingress/egress cutout opening at all door positions, said programming mechanism defining means including:
• (i) a bell crank pivotally mounted on said L-shaped hinge element at the juncture between said relatively long and relatively short hinge arms, said bell crank defining a first crank arm having a length "a" and a second crank arm having a length "b";
• (ii) a first control link pivotally connected at one end to the free extremity of said first crank arm and at its opposite end to said one of the generally vertical fore and aft frame members at a point located a distance "a" from said first generally vertical hinge axis;
• and (iii), a second control link pivotally connected at one end to the free extremity of said second crank arm and at its opposite end to said aircraft door at a point located a distance "b" from said second generally vertical hinge axis;
• whereby said relatively short hinge arm, first crank arm, first control link and the distance "a" intermediate said first generally vertical hinge axis and the point of pivotal connection between said first control link and said one of the generally vertical fore and aft frame members define a first parallelogram at all positions of said aircraft door ranging from a fully closed unlatched position to a fully opened position;
• and, said relatively long hinge arm, said second crank arm, said second control link and the distance "b" intermediate said second generally vertical hinge axis and the point of pivotal connection between said second control link and said door define a second parallelogram at all positions of said aircraft door ranging from a fully closed unlatched position to a fully opened position.

An outward opening plug-type aircraft door of the type adapted to be mounted in an ingress/egress cutout opening formed in the aircraft fuselage and bounded by generally vertical fore and aft fuselage frame members, said door comprising, in combination:

• (a) means defining a generally L-shaped hinge element having a relatively short hinge arm and a relatively long hinge arm;
• (b) means for securing said relatively short hinge arm to one of the generally vertical fore and aft frame members bounding the ingress/egress cutout opening in the aircraft fuselage with freedom for rotation about a first generally vertical hinge axis;
• (c) an outwardly opening plug-type aircraft door dimensioned to be received in and to close the ingress/egress cutout opening in the aircraft fuselage, said door being mounted in cantilever fashion on the free extremity of said relatively long hinge arm for rotation about a second generally vertical hinge axis and with freedom for limited up and down vertical movement relative to said hinge element and the ingress/egress cutout opening in the aircraft fuselage;
• (d) means defining a programming mechanism interconnecting said aircraft door, said hinge element and said one of the fore and aft fuselage frame members for controlling the rotational attitude of said aircraft door as the latter is shifted between fully closed and fully opened positions and for maintaining said aircraft door in a plane essentially parallel to the plane conatining the ingress/egress cutout opening at all door positions, said programming mechanism defining means comprising a double 4-bar linkage assembly such that the ingress/egress cutout opening in the aircraft fuselage is essentially devoid of any obstructions when said aircraft door is in the fully open position;
• (e) cooperable latch means mounted on the fore and aft vertical edges of said aircraft door and on the fore and aft generally vertical fuselage frame members bounding the ingress/egress cutout opening for selectively latching said aircraft door in a seated, fully closed and latched condition, said cooperable latch means including an open-ended latch track mounted on each of the fore and aft fuselage frame members bounding the cutout opening and cooperable latch rollers projecting fore and aft from respective ones of the fore and aft edges of said door with freedom for movement outboard along said tracks during door opening movement and inboard along said tracks during door closing movement;
• and,
• (f) manually operable actuating means mounted on said aircraft door for lifting said aircraft door within the fuselage ingress/egress cutout opening a distance on the order of approximately two inches from a seated, fully latched and closed position to a raised unlatched and closed position and for lowering said aircraft door within the fuselage ingress/egress cutout opening a distance on the order of approximately two inches from a raised, unlatched and closed position to a seated, fully latched and closed position, said manually operable actuating means including cam track defining means, cam follower means, an inner main operating handle rotatably mounted on said door, a latch torque tube extending transversely across said door and journaled for rotation therein, said latch torque tube projecting beyond the fore and aft vertical edges of said door, fore and aft latch cranks mounted on respective ones of said fore and aft projecting portions of said torque tube, and first control linkage defining means drivingly interconnecting said handle and said torque tube for causing rotation of said torque tube during a portion of rotational movement manually imparted to said handle;
• and, wherein said latch rollers are mounted on respective ones of said fore and aft latch cranks, said handle is connected to one of said cam track defining means and said cam follower means;
• said first control linkage defining means is connected to the other of said cam track defining means and said cam follower means;
• and, said cam track defining means is profiled as a single continuous cam track so as to cause movement of said first control linkage defining means and consequent rotation of said torque tube during a selected portion only of handle rotation with said first control linkage defining means being in a stationary dwell position during all other portions of handle rotation;
• whereby rotational movement of said handle causes rotation of said torque tube and said latch cranks and, as a result of mutual coaction between said latch rollers and said latch tracks, said door is lifted during a door unlatching operation and lowered during a door latching operation by an amount equal to the effective length of said latch cranks;
• whereby said aircraft door may be shifted between a seated, fully latched and closed position and a raised, unlatched and closed position by manual actuation of said actuating means;
• and, whereby said aircraft door, when in a raised, unlatched and closed position, can be manually shifted out of the ingress/egress cutout opening to a fully open position wherein said door is located outboard of the aircraft fuselage with the door's inner surface and the fuselage outer surface in facing relation with said door being maintained in a plane essentially parallel to the plane containing the ingress/egress cutout opening at all door positions intermediate a fully closed and fully opened position and with the ingress/egress cutout opening being substantially devoid of laterally projecting hinge and/or actuating components when said door is fully opened.