How many full brake applications will the parking/emergency brake accumulator provide?

How many full brake applications will the parking/emergency brake accumulator provide?

• A. 4
• B. 6
• C. 8
• D. 10

Answer: (B)

The main idea is that the parking/emergency brake accumulator provides a finite amount of stored hydraulic energy so you can still get full brake action even if the normal hydraulic source is lost. This accumulator is charged during normal operation and then used when you engage the parking brake, feeding the brake actuators with a burst of pressure independent of the primary system. Its size and pre-charge are chosen so that you can get a limited but usable number of full brake applications—typically six. After those six uses, the stored energy is depleted and you won’t get full braking from the accumulator alone, meaning you’d need to rely on other means or re-pressurize the system. This design gives enough ability to stop or taxi to a safe area after a hydraulic fault, without requiring immediate maintenance.

The main idea is that the parking/emergency brake accumulator provides a finite amount of stored hydraulic energy so you can still get full brake action even if the normal hydraulic source is lost. This accumulator is charged during normal operation and then used when you engage the parking brake, feeding the brake actuators with a burst of pressure independent of the primary system. Its size and pre-charge are chosen so that you can get a limited but usable number of full brake applications—typically six. After those six uses, the stored energy is depleted and you won’t get full braking from the accumulator alone, meaning you’d need to rely on other means or re-pressurize the system. This design gives enough ability to stop or taxi to a safe area after a hydraulic fault, without requiring immediate maintenance.