DEVICE FOR BRINGING AN AIRCRAFTS WHEELS TO GROUND SPEED BEFORE LANDING, THEN FOR COOLING THE BRAKE DISKS AFTER LANDING

摘要

The invention discloses a device for bringing an aircrafts wheels to ground speed before landing, then for cooling the brake disks after landing. It consists of brass pipes (7) attached on the sliding tube (3) and terminated by wind nozzles (12) and cooling nozzles (25) on which are fixed electrovalves (20 and 21) opening the passage for compressed air. This device located on a bogie wheel rim (9) is designed first to start the wheel rotating before landing and subsequently to cool the overheated brake disks (23) at the time of landing. The compressed air is provided by reserve gas cylinders supplied by the 14 or 15 stage gas off-take valve of the engine high pressure compressor. Ten minutes before descent, the empty cylinders are charged to 30 kg pressure with compressed air on the pilot's command. The electrovalves on the reserve cylinder are automatically operated as soon as the undercarriage is locked; then the electrovalves (20) on the delivery spider (11) are automatically operated by an altitude sensor set to 2000 feet above ground to start rotating the wheels. Then a temperature sensor set at 50 DEG (22) actuates the electrovalves (21) for cooling the brakes (23) from the moment braking starts until the plane comes to a complete stop. The device is particularly designed to avoid tyre deformation or even bursting at touchdown during landing and then to cool down and ventilate the overheated brake disks at landing and during acceleration-stop manoeuvres.