The brake system is considered inoperative if the primary hydraulic system fails. Which of the following is correct?

• A. True
• B. False
• C. The brake system remains operative if the hydraulic system fails
• D. The brakes automatically apply when hydraulic pressure drops

Answer: (B)

Redundancy in braking systems means there’s more than one source of hydraulic power. If the primary hydraulic system fails, a secondary (alternate) hydraulic system can still pressurize the brakes, so braking action can continue. Because of this backup capability, the brakes are not necessarily inoperative when the primary system fails. The idea that braking would automatically apply simply due to pressure dropping isn’t how braking works, and there would only be a loss of braking if both hydraulic systems failed.