Typical Brake Installation

This installation uses an 10-35 master cylinder with built-in reservoir on pilot side (1). When dual brakes are required, add a 10-20 master cylinder to co-pilot side (2) and plumb as shown. This is a fail-safe design. If one master cylinder should fail, the other one will still operate. A 10-20 master cylinder could be used on both sides but would require an external brake fluid reservoir (Model A-315). These cylinders are used in this type of installation on American Aviation, Aero Commander, Maule, Bellanca, Beechcraft and other production aircraft. BRAKE SYSTEM BASICS PRESSURE AND STROKE With no change in mechanical advantage and with the same push on the pedal, if the bore size of the master cylinder is decreased the fluid pressure in pounds per square inch(PSI) increases and the stroke increases. For example, a 100-lb. push on the pedal and a 4:1 mechanical advantage (pedal ratio) gives a 400-1b. push on the master cylinder. With a 7/8 in. bore master cylinder, the piston area is 0.60 sq. in. the pressure developed is 400/0.06 = 667 PSI and the stroke to move 0.6 cu. in. of fluid is 0.6/0.60 = 1 in With a 3/4 in bore master cylinder, the piston area is 0.44 sq. in.; the pressure developed is 400/0.44 = 909 PSI and the stroke to move 0.6 cu in. of fluid is 0.6/0.44 = 1.4 in.