What is a dual brake system?

A dual brake system refers to a braking mechanism that incorporates both air brakes and hydraulic brakes within the same vehicle. This design enhances safety and braking effectiveness by providing an additional layer of redundancy; if one system fails, the other can still function to stop the vehicle.

In vehicles equipped with a dual brake system, the air brake system is typically used for the major stopping power, especially in larger vehicles like trucks and buses, while hydraulic brakes may take over in scenarios where lighter stopping force or faster engagement is required. The combination of these two systems ensures improved control and performance in a variety of driving conditions, particularly for larger and heavier vehicles that demand greater braking capability.

The other options do not accurately describe a dual brake system. A system that uses only air brakes would lack the safety benefits provided by the hydraulic system, while a system that uses hydraulic brakes only would not benefit from the reliability and effectiveness of air brakes. A system with no brakes at all is obviously unsafe and not functional for a vehicle.