Abstract: A bypass valve assembly for a gas turbine engine includes a frame defining a first flow channel in flow communication second and third flow channels separated by a splitter. A plurality of circumferentially juxtaposed bypass doors are disposed in the second channel and are positionable between a closed position preventing airflow into the second channel and an open position providing for substantially unobstructed airflow into the second channel. Means for automatically positioning the doors in the open and closed positions in response to differential pressure across the doors in the second channel include a spring which provides a closing torque on the door which decreases for at least a portion of the travel of the doors from the closed to open position.

Abstract: An incoming airstream is channeled into a diffuser to reduce its spread. Heating coils heat the air in order to vaporize any water present. Then, a collection pipe draws off a portion of vaporized mixture and transmits it to a dew point meter at which the water content is ascertained. The remaining mixture bypasses the collection pipe and is expelled.