An aircraft comprising a fastening element and an engine pylon with two rear covers. Each cover includes a movable lower cover mounted articulated on a rear portion in which in the closed position, the two movable lower covers are moved together and in which in the open position, they are tilted and moved apart from each other. For each movable lower cover, a hinge system, and at least one locking system locks the two movable lower covers together in the closed position and locks each movable lower cover to the fastening element in the open position. The presence of the movable lower covers provides, inter alia, easy access to the inside of the engine pylon, and the locking system locks the movable lower covers.