Patent ID: 7677500

Claim:
An aircraft structural element having a cavity with a wall, the wall including an opening through which moisture located in the cavity can escape into the surroundings external to the aircraft, and a drainage element configured to seal the opening, the drainage element comprising: a hollow cylinder that connects the cavity of the structural element to the surroundings; the hollow cylinder having an external thread having a predefined external diameter, a head at one end of the hollow cylinder that has a predefined head diameter, wherein the predefined external diameter of the external thread is smaller than the predefined head diameter; wherein the head diameter is greater than a diameter of the opening and the external thread diameter of the hollow cylinder has a diameter less than the diameter of the opening to allow the drainage element to be inserted into the opening, wherein the head is retained in an interior of the cavity and the hollow cylinder extends through the opening, the hollow cylinder having a passage connecting the cavity of the structural element to the surroundings.