Which action best balances fuel between left and right tanks during flight?

• A. Monitor quantities and use crossfeed as necessary to balance at critical phases.
• B. Ignore balance and rely on tanks automatically balancing.
• C. Swap tanks manually after touchdown.
• D. Lock out crossfeed to avoid crossflow.

Answer: (D)

Balancing fuel between the left and right wings during flight is about keeping the airplane’s center of gravity within safe limits by using the crossfeed system to transfer fuel as needed. By monitoring how much fuel sits in each wing, you can transfer fuel from the heavier side to the lighter side to prevent a lateral imbalance that could affect handling or CG position.

Using crossfeed proactively helps maintain a symmetrical fuel load throughout the flight, especially as tanks drain at different rates due to engine out situations, climb, cruise, or descent. Locking crossfeed out stops this balancing mechanism, so any imbalance would have to be absorbed by the aircraft’s weight distribution and could lead to a less favorable CG range or handling characteristics. Swapping tanks after touchdown is irrelevant to in-flight balance, and ignoring balance altogether invites larger and potentially unsafe imbalances.

So, the recommended practice is to monitor quantities and use crossfeed as necessary to maintain balance at critical phases of flight.