Monitor for uncommanded braking

摘要

The monitor for uncommanded braking controls uncommanded brake application on one or more wheels during takeoff of an aircraft. Brake pedal application is determined, brake pressure is measured, and brake pressure is compared with a selected threshold brake pressure. A brake pressure applied signal is generated when the brake pressure exceeds the threshold brake pressure. The pedal application signal and brake pressure applied signal are received by a fault latch logic circuit that generates a fault latch output signal when uncommanded braking has occurred. A test inhibit signal is also generated when weight is not applied on the wheel. The test inhibit signal is also input to the fault latch logic circuit so that uncommanded braking can occur when the aircraft is in the air and weight is off the wheel. The monitor disables or latches off the shutoff valve when pressure is detected without pedal application. A fail-safe feature re-enables the shutoff valve to allow it to turn on, and monitoring is stopped, when pedal application is detected.