3. Brake controls

3.1 Power source

Braking is always controlled from a pressure source generated by the aircraft. Braking pressure is set by a hydraulic pressure reducer controlled by the brake pedals.

Pneumatic power was abandoned on Western aircraft in the 40s and 50s. It is still used on some recent ex-USSR aircraft.

Hydraulic control :

— All Western civil aircraft use ester-phosphate fluids, generically known as Skydrol (Monsanto), which are reputed to be low flammability. The disadvantage of the former was that they rapidly eroded the distributors.

The Concorde supesonic uses a high-temperature liquid ester-silicate made by Chevron, called Oronite.

These fluids are also used on...