Patent ID: 9022319
Filing Date: 2015-05-05
Classification: B64D,F25B

Abstract:
1. An environmental control system comprising: an inlet duct for receiving inlet hot at least one heat exchanger in a path of the hot air between the inlet duct and an outlet to cool the hot air, a fan to pull ram air for cooling the hot air across the at least one heat exchanger; first and second stage turbines for driving said fan, the hot air passing downstream of the at least one heat exchanger to be compressed by a compressor, and then driving said first stage turbine, said first stage turbine having an outlet communicating with a condenser, and said condenser having an outlet communicating with said second stage turbine; and an icing control system including a tap passage tapping hot air downstream of said compressor, the tapped hot air passing to an add heat valve, the add heat valve being selectively moveable between three positions, including a first position where the add heat valve blocks flow from said tap passage into a condenser line leading to an inlet to said condenser, a second position where the add heat valve passes air from said tap passage both into said condenser line, and further to a point downstream of said condenser and passing to said second stage turbine, and a third position wherein said add heat valve only communicates air from said tap passage into said condenser line leading to said condenser inlet.