Air Brake Test Air Brake Driving Techniques & Vehicle Control

Question 1

When driving downhill with air brakes, what is the recommended braking technique to prevent brake fade?

Accepted Answer

Snub braking — apply firm pressure, release, then repeat

Answer

Snub braking allows brakes to cool between applications, preventing the overheating that causes brake fade.

Question 2

What is 'brake fade' and when does it most commonly occur?

Accepted Answer

Reduced braking effectiveness caused by overheated friction materials

Answer

Brake fade occurs when friction materials overheat, reducing their ability to create the friction needed to slow the vehicle.

Question 3

What should you do BEFORE starting down a long, steep downhill grade?

Accepted Answer

Test brakes and select an appropriate low gear before the descent begins

Answer

Selecting the correct low gear before the descent uses engine braking to help control speed, reducing reliance on service brakes.

Question 4

What is 'stab braking' and when is it used?

Accepted Answer

Applying full brake pressure until wheels lock, then fully releasing to restore steering, repeating as needed

Answer

Stab braking is a technique for vehicles without ABS that applies full pressure until lockup, then releases to restore steering control.

Question 5

What should you do if your brakes become dangerously hot after a long downhill grade?

Accepted Answer

Pull over and allow brakes to cool naturally through rest before continuing

Answer

Hot brakes must cool naturally through rest; continuing to drive with overheated brakes risks complete brake failure.

Air Brake Practice Test Practice Test