AMT Aircraft Weight and Balance 2 — Questions and Answers
Question 1: An aircraft has an empty weight of 1,650 lbs with a CG at 87.0 inches. After adding equipment weighing 30 lbs at 130 inches, what is the new CG?
- 87.8 inches (Correct answer)
- 89.0 inches
- 91.5 inches
- 85.2 inches
Correct answer: 87.8 inches
New moment = (1,650 × 87) + (30 × 130) = 143,550 + 3,900 = 147,450; new weight = 1,680; CG = 147,450 ÷ 1,680 ≈ 87.8 inches.
Question 2: What is the term for the distance between the datum and the CG of an item?
- Moment arm (Correct answer)
- Lever arm
- Reference arm
- Balance arm
Correct answer: Moment arm
The moment arm is the horizontal distance from the datum to the center of gravity of an item, used to calculate its moment.
Question 3: Which document establishes the forward and aft CG limits for a certificated aircraft?
- Type Certificate Data Sheet (TCDS) (Correct answer)
- Aircraft weight and balance report
- Weight and balance loading chart
- Airworthiness Directive
Correct answer: Type Certificate Data Sheet (TCDS)
The Type Certificate Data Sheet (TCDS) issued by the FAA defines the approved CG range and weight limits for certificated aircraft.
Question 4: When an aircraft's CG is too far AFT, the most likely hazard is:
- Reduced longitudinal stability and possible unrecoverable stall (Correct answer)
- Excessive nose-down tendency during climb
- Reduced elevator effectiveness during landing
- Increased drag due to high angle of attack
Correct answer: Reduced longitudinal stability and possible unrecoverable stall
An aft CG reduces longitudinal stability, which can make pitch control difficult and may result in an unrecoverable stall or spin.
Question 5: A useful load includes which of the following?
- Crew, fuel, passengers, and cargo (Correct answer)
- Engine, avionics, and fixed equipment
- Empty weight plus oil
- Basic empty weight only
Correct answer: Crew, fuel, passengers, and cargo
Useful load is the difference between maximum gross weight and basic empty weight, and includes crew, usable fuel, passengers, and cargo.
Question 6: What effect does fuel burn have on CG if fuel tanks are located forward of the CG?
- CG shifts aft (Correct answer)
- CG shifts forward
- CG remains unchanged
- CG shifts laterally
Correct answer: CG shifts aft
Burning fuel from tanks located forward of the CG removes forward moment, causing the CG to shift aft.
Question 7: A ballast of 15 lbs must be placed to move the CG 2 inches forward on a 1,500 lb aircraft. Where must the ballast be placed relative to the CG?
- 200 inches forward of the CG (Correct answer)
- 20 inches forward of the CG
- 150 inches forward of the CG
- 45 inches forward of the CG
Correct answer: 200 inches forward of the CG
Using the formula: distance = (weight × CG shift) ÷ ballast weight = (1,500 × 2) ÷ 15 = 200 inches forward of CG.
AMT Aircraft Weight and Balance 2
An aircraft has an empty weight of 1,650 lbs with a CG at 87.0 inches.
After adding equipment weighing 30 lbs at 130 inches, what is the new CG?