Field of the Invention
The present invention relates to a door which is provided on an airframe surface of an aircraft.
Description of the Related Art
In aircraft, a door for opening and closing an opening of a storage bay for a ram air turbine (RAT, e.g., U.S. Pat. No. 5,820,074) or a door for opening and closing an opening of a storage bay for an landing gear (e.g., Japanese Patent Laid-Open No. 2010-195149) is provided as well as a door for opening and closing an opening for allowing passengers to enter and exit the aircraft, and an opening for loading and unloading cargos.
The RAT is normally stored in a storage bay provided in, for example, a center lower portion of a fuselage. In the event of an emergency in which an engine (including a power generator of the engine, the same applies hereinafter) and an auxiliary power unit break down and power from the engine and the auxiliary power unit is lost during a flight, the RAT is automatically deployed outside the aircraft to work as a wind-driven power generator or hydraulic pump and thereby ensure a drive force for emergency use. A door for opening and closing the storage bay for the RAT (referred to as RAT door below) is opened in synchronization with the automatic deployment of the RAT. The RAT door is provided so as to be rotatable about a shaft provided between the RAT door and an airframe with respect to the airframe. For example, the RAT door is powered by a hydraulic actuator to perform an opening and closing operation.
The door provided in the storage bay for the RAT is opened in association with the deployment of the RAT. When an opening degree of the door is still small in an initial stage of the deployment of the RAT, an aerodynamic force acts in a direction to close the door to possibly prevent the door from being opened. Thus, the aerodynamic force affects the capacity of the actuator for operating the door. In other words, if the aerodynamic force on the door can be reduced, the actuator requires a smaller capacity. A weight and a cost related to the door can be thereby reduced.
Thus, an object of the present invention is to provide an aircraft door capable of suppressing generation of an aerodynamic force acting in a direction to close the door in an initial stage where the door starts to be opened.