How many minutes are required to fully recharge the APU start accumulators?

The correct duration required to fully recharge the APU start accumulators is 5 minutes. This timeframe is based on the technical specifications and operational guidelines for the C-5 aircraft's Auxiliary Power Unit (APU). Understanding the significance of this recharging cycle is essential for operational efficiency and flight safety.

The 5-minute recharge period ensures that the accumulators reach the necessary pressure and capacity to provide reliable starting power for the APU, which is critical for systems requiring electrical and pneumatic power. Maintaining this specific timeframe prevents potential overheating and maintains the integrity of the accumulators, thereby prolonging their service life and ensuring optimal performance during aircraft operations.

Knowing the correct recharge time allows maintenance personnel and flight crews to schedule their operations effectively, ensuring that the APU is always ready for use when required.