What is the maximum planned imbalance between the wing tanks?

What is the maximum planned imbalance between the wing tanks?

• A. 2,000 lbs in flight
• B. 1,000 lbs on ground; None in flight
• C. 500 lbs on ground; 500 lbs in flight
• D. None on the ground; 1,000 lbs in flight

Answer: (D)

This question is about how much imbalance between the wing tanks is allowed during different phases of flight. The balance of fuel between the wings affects the airplane’s center of gravity and its roll stability, so limits are set to keep handling within safe bounds. On the ground, no deliberate imbalance is allowed because the airplane sits on its landing gear, and any uneven weight distribution can cause uneven gear loads or tipping during such operations as towing or fueling. In flight, a small imbalance can be tolerated because the aircraft has enough roll authority and the CG stays within the certified envelope; up to 1,000 pounds difference is considered acceptable and manageable, with fuel transfer or crossfeed used if needed to rebalance. So the correct approach is zero imbalance on the ground and up to 1,000 pounds in flight.

This question is about how much imbalance between the wing tanks is allowed during different phases of flight. The balance of fuel between the wings affects the airplane’s center of gravity and its roll stability, so limits are set to keep handling within safe bounds.

On the ground, no deliberate imbalance is allowed because the airplane sits on its landing gear, and any uneven weight distribution can cause uneven gear loads or tipping during such operations as towing or fueling. In flight, a small imbalance can be tolerated because the aircraft has enough roll authority and the CG stays within the certified envelope; up to 1,000 pounds difference is considered acceptable and manageable, with fuel transfer or crossfeed used if needed to rebalance.

So the correct approach is zero imbalance on the ground and up to 1,000 pounds in flight.