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What happens if a driver tries to compound the brakes by making a full service application while the spring brakes are already applied?
- A.Compounding improves stopping with no downside
- B.The governor resets itself automatically
- C.Only the trailer is affected by compounding
- D.The combined forces can damage brake components such as chambers, slack adjusters, and drums
Correct answer
D. The combined forces can damage brake components such as chambers, slack adjusters, and drums
Why
Service and spring forces stack on the same mechanical parts, and the total can exceed what they were built to take. Anti-compounding valves protect many systems, but drivers should still avoid the practice.
Manual topic: Air Brakes - Spring Brakes and Parking Brakes · From the Air Brakes practice bank (AB-116).