Above what altitude must both boost pumps be on to prevent feed tank failure?

Above what altitude must both boost pumps be on to prevent feed tank failure?

• A. 6000 ft MSL
• B. 8000 ft MSL
• C. 9000 ft MSL
• D. 10000 ft MSL

Answer: (B)

Boost pumps keep positive pressure in the fuel feed line to the engine. As you climb, ambient pressure drops, and the pressure head from a single boost pump may not be enough to push fuel reliably to the engine and feed tank, especially during high power or certain attitudes. To prevent fuel starvation or vapor-related issues in the feed system, the MH-65E requires both boost pumps to be on above 8,000 feet MSL. With both pumps supplying pressure, the fuel system maintains adequate flow to the engine-driven pump and keeps the feed tank pressurized, reducing the risk of feed tank failure. Below 8,000 feet, one pump usually provides sufficient pressure for normal operation.

Boost pumps keep positive pressure in the fuel feed line to the engine. As you climb, ambient pressure drops, and the pressure head from a single boost pump may not be enough to push fuel reliably to the engine and feed tank, especially during high power or certain attitudes. To prevent fuel starvation or vapor-related issues in the feed system, the MH-65E requires both boost pumps to be on above 8,000 feet MSL. With both pumps supplying pressure, the fuel system maintains adequate flow to the engine-driven pump and keeps the feed tank pressurized, reducing the risk of feed tank failure. Below 8,000 feet, one pump usually provides sufficient pressure for normal operation.