New Jersey Air Brakes Practice Test

What happens if one system loses pressure in a dual air brake system?

1. Both systems will immediately fail

2. Either the front or back brake will not be fully operational

3. The air pressure will equalize between both systems

4. The pressure warning light will activate

The correct answer is: Either the front or back brake will not be fully operational

In a dual air brake system, if one system loses pressure, it typically results in a situation where either the front or back brake will not be fully operational. The dual air brake system is designed for safety; it separates the braking functions into two systems, so that if one fails, the other can still function. When pressure is lost in one of the systems, the other system can continue to operate, allowing for some braking capability. However, the system that lost pressure will be unable to provide full braking force, which compromises the overall braking effectiveness. This design minimizes the risk of complete brake failure by ensuring that at least one of the brake systems remains functional. In contrast, if both systems were to fail, or if the air pressure were to equalize between the systems, or if a warning light were to activate, the situation would present a more severe safety risk and would not provide the same level of operational redundancy that a dual air brake system is intended to provide.