Improvements in doors for pressurized fuselages of aircraft

868,390. Closures for resisting fluid pressure. VICKERS AIRCRAFT HOLDINGS Ltd. June 9, 1959 [July 4, 1958], No. 21523/58. Class 123(1) [Also in Groups XXV and XXXIII] The door and door frame of a pressurised aircraft cabin are each provided about its periphery with a set of spaced lugs, the arrangement of the lugs being such that when the door is closed and the cabin pressurised the lugs on the door abut their outward faces against the inward faces of the lugs on the door frame to positively resist outward pressure on the door, means being provided, operable from within the cabin, whereby after decompression thereof, the door can be raised with respect to the frame to disengage the abutting faces of the opposed lugs, the door lugs being moved to positions intermediate the frame lugs, permitting the door to be opened. The door 10 fits within a frame 11 upon a main hinge 13 so constructed that, under the restraint of a pivoted tie member 26, the door in opening moves bodily outwards from the cabin. The door is connected to hinge 13 through a parallel linkage 21 which permits vertical movement of the door when an operating handle 18 projects spring loaded feet 19 in the base of the door into contact with a sill member 111. During such vertical movement the door is guided at its upper end by spigots 23 which engage slotted plates on the door frame. The door is provided on its peripheral edges with lugs 14 which, when the door is closed, cooperate as shown with matching lugs 15 on the door frame whereby pressure loads on the door are reacted directly by the frame and not the hinge and latching mechanism. The final latching movement causes locking spigots 16 in the door to project into holes in the door frame. Initial movement of handle 18 withdraws such latches and then causes feet 19 to project on to the sill and raise the door to a position in which lugs 14 can pass between lugs 15 when the door is opened. A conventional pressure seal is provided.