Abstract: An air brake control system of high reliability is provided for a vehicle of the type having front wheel brakes, rear wheel brakes, a first brake control element such as a pedal which actuates the front and rear brakes, and a second brake control element such as a pedal which also actuates the front and rear brakes. First and second pneumatic circuit means for controlling the brakes are duplicated back to the outlet of the air compressor in an arrangement where one side of the circuit is automatically isolated from the other to maintain braking capacity if a loss of air pressure occurs on the one side. Means is associated with air streams of only a selected one of the first and second means for providing a function absent in said first and second means.

Abstract: An air brake control system of high reliability is provided for a vehicle of the type having front wheel brakes, rear wheel brakes, a first brake control element such as a pedal which actuates the front and rear brakes, and a second brake control element such as a pedal which also actuates the front and rear brakes. First and second pneumatic circuit means for controlling the brakes are duplicated back to the outlet of the air compressor in an arrangement where one side of the circuit is automatically isolated from the other to maintain braking capacity if a loss of air pressure occurs on the one side. Means is associated with air streams of only a selected one of the first and second means for providing a function absent in said first and second means. A transmission neutralizer is also operated by one of the pedals.