Abstract: A canopy door including a pivotally mounted leaf adapted to swing on a fixed horizontal axis between an open and a closed position, and an extensible strut having an intermediate pivot point disposed in an over-center position when the door is closed. Operating cables, driven by a common shaft, are attached to the leaf and strut; and are payed out and taken up to move the door between its open and closed positions. One of the operating cables exerts an upward force on the strut to move it from its over-center position, thereby exerting an initial outward opening force on the door.