BAvn Bachelor of Aviation Aircraft Performance and Weight & Balance 2 — Questions and Answers
Question 1: What is the 'arm' in aircraft weight and balance calculations?
- The horizontal distance from the datum to a component (Correct answer)
- The vertical height of the aircraft's CG
- The weight of a specific component
- The moment divided by total weight
Correct answer: The horizontal distance from the datum to a component
The arm is the horizontal distance measured from the aircraft datum to the point where a weight acts, used to calculate moment.
Question 2: How is an aircraft's moment calculated in weight and balance?
- Weight ÷ Arm
- Weight × Arm (Correct answer)
- Arm ÷ Weight
- Weight + Arm
Correct answer: Weight × Arm
Moment = Weight × Arm; it represents the rotational tendency of a load about the datum reference point.
Question 3: A pilot adds 50 lb of baggage to the rear cargo compartment. What happens to the aircraft's CG?
- Moves forward
- Moves aft (Correct answer)
- Remains unchanged
- Moves laterally
Correct answer: Moves aft
Adding weight behind the existing CG increases the aft moment, shifting the overall CG rearward.
Question 4: What is the significance of the aft CG limit in aircraft certification?
- It defines maximum fuel load
- It marks the point beyond which the aircraft may become longitudinally unstable (Correct answer)
- It determines maximum crosswind component
- It establishes the minimum landing weight
Correct answer: It marks the point beyond which the aircraft may become longitudinally unstable
When CG moves aft of the certified limit, the aircraft's longitudinal stability decreases, potentially making it uncontrollable.
Question 5: Which of the following is included in 'Basic Empty Weight' of an aircraft?
- Usable fuel and pilot
- Unusable fuel, oil, and standard equipment (Correct answer)
- Payload and baggage
- Maximum fuel load only
Correct answer: Unusable fuel, oil, and standard equipment
Basic Empty Weight includes the airframe, engines, and all items permanently installed, plus unusable fuel and full oil.
Question 6: During climb, as fuel is burned from a forward fuel tank, what generally happens to the CG?
- CG moves forward
- CG moves aft (Correct answer)
- CG is unaffected by fuel burn location
- CG rises vertically
Correct answer: CG moves aft
Burning fuel from a forward tank removes weight forward of the CG, reducing the forward moment and causing the CG to shift aft.
Question 7: What does 'zero fuel weight' represent?
- Aircraft weight with no crew on board
- Maximum allowable weight of the aircraft excluding all usable fuel (Correct answer)
- Weight at landing after fuel burn
- Empty weight minus oil weight
Correct answer: Maximum allowable weight of the aircraft excluding all usable fuel
Maximum Zero Fuel Weight (MZFW) is the maximum permissible weight without usable fuel, limiting wing bending loads at the root.
BAvn Bachelor of Aviation Aircraft Performance and Weight & Balance 2
What is the 'arm' in aircraft weight and balance calculations?