Dual function door for an aircraft engine nacelle

A door (20) for an aircraft engine nacelle (6), said door comprising an opening leaf (22) designed so as to be able to occupy a closed position and an open position, said door comprising locking means (32, 36) with which the opening leaf may be locked in the closed position, as well as means (28) for setting the opening leaf (22) into motion with which the latter may be moved from the closed position towards the open position when the locking means (32, 36) are disabled,

• characterized in that said locking means (32, 36) have a mechanical fuse (50) provided in order to break under the effect of a force exerted by the opening leaf (22) and resulting from an opening gas pressure (66) which is applied on the opening leaf, with a value greater than or equal to a predetermined value and causing the displacement of said opening leaf from the closed position to the open position after breakage of said mechanical fuse (50).