Abstract: A fence 30A is installed on an inner surface 21a of a door 20A on the side which faces a landing gear bay 15, the fence 30A rising inwardly of the airframe from the inner surface 21a. When the door 20A opens outwardly of an airframe due to a pressure difference between the side of an outer surface 21c of the door 20A and the side of an inner surface 21a facing inner part of the landing gear bay 15 during a flight of an aircraft 10, the fence 30A closes a gap between the door 20A and an opening 15a of the landing gear bay 15, and thereby prevents air from flowing into the landing gear bay 15 through the gap.

Abstract: A sealant 34 filled into a cap 30A is caused to overflow through both an opening in a first end portion 30a of the cap 30A and a through-hole 40 of the cap 30A when the cap 30A is pressed against a fastener member 25. With regard to the cap 30A, a ratio between inside diameter D1 of the opening on the side of the first end portion 30a and hole diameter D2 of the through-hole 40 in the second end portion 30b is set as follows: 0.10?D2/D1 ?0.27.

Abstract: The present invention prevents misassembly of access doors while reducing stress concentrations. A hole-side convex portion 80 is formed in each opening 12 at one or more locations in a circumferential direction, and a door-side rib 70 is formed on each door body 30. The hole-side convex portions 80 formed in the openings 12A to 12C differ in location in the circumferential direction among the plural openings 12A to 12C. The door-side ribs 70 formed on the respective door bodies 30A to 30C are provided in such locations as not to interfere with the hole-side convex portions 80 provided in the openings 12A to 12C in correct combination with the door bodies 30A to 30C.