Abstract: A latch and lock mechanism for an aircraft cargo door assembly is disclosed. The mechanism is adapted to a cargo door assembly of the type having an outwardly opening, nonplug-type cargo ramp and an inwardly opening, plug-type cargo door hinged to opposite sides of a doorway so as to form a two-part closure member in coplanar alignment with the airplane fuselage when the door assembly is closed. The latch and lock mechanism preferably includes a plurality of latch units that secure the cargo ramp in its closed position. The latch units are connected through a cam-actuated interlock mechanism to the plug-type cargo door. The interlock mechanism is such that the cargo ramp latches can only be actuated when the cargo door is in an open position, and further such that the cargo door cannot be closed unless the cargo ramp latches are in a latched position.