A lever mechanism for holding an escape hatch onto a vehicle surface covering an opening in the vehicle surface, for enabling emergency escape through the escape hatch. The lever mechanism includes a base portion, a handle portion and a clamp portion, with the handle portion and clamp portion linked so that by pushing on the handle portion, and so placing the lever mechanism in its engaged state, the clamp portion is pushed against the vehicle surface, drawing the escape hatch against the vehicle surface. By pulling on the handle portion of the lever mechanism, and so placing the lever mechanism in its disengaged state, the clamp is pulled up and away from the vehicle surface and clear of the opening in the vehicle surface, thus allowing the escape hatch to be pushed out away from the vehicle surface, thereby enabling emergency egress.