Which statement about cross flow during takeoff is correct?

• A. Neither can be on for takeoff.
• B. Powered cross flow may be used for takeoff, but gravity cross flow cannot.
• C. Gravity cross flow may be used for takeoff, but powered cross flow cannot.
• D. Both powered and gravity cross flow may be used for takeoff.

Answer: (D)

Crossflow during takeoff is about moving fuel between tanks to keep the airplane within its center-ofgravity limits and ensure reliable fuel to the engines. You can accomplish this either by gravity crossflow, which relies on the hydrostatic head between tanks, or by powered crossflow, which uses a pump to drive fuel through the crossfeed line. Because each method serves different conditions and can be used as needed, both powered and gravity cross flow may be used for takeoff. The other options would unnecessarily limit which method can be used or suggest none can be used, which isn’t accurate.