Aircraft Drawings

When an empty aircraft is weighed, the combined net weight at the main gears is 3,540 pounds with an arm of 195.5 inches. At the nose gear, the net weight is 2,322 pounds with an arm of 83.5 inches. The datum line is forward of the nose of the aircraft. What is the empty CG of the aircraft?

• 151.1.

• 155.2.

• 146.5.

Answer explanation

ITEM WEIGHT ARM MOMENT
Main wheels 3,540 195.5 692,070
Nose wheel 2,322 83.5 193,887
TOTAL 5,862 151.14 885,957

The empty weight of this aircraft is 5,862 pounds, and its empty-weight CG is located at fuselage station 151.14.

When, or under what condition(s) are adverse loading checks conducted?

• At or below the maximum gross weight of the aircraft.

• Anytime a repair or alteration causes EWCG to fall outside the CG range.

• At specified flight hour or calendar time intervals.

Answer explanation

When a repair or alteration of an aircraft has been made that causes the empty weight-center of gravity to fall outside the empty weight CG range, an adverse-loaded CG check should be conducted to determine whether or not it is possible to load the aircraft in such a way that its operational CG will fall outside of its allowable limits.

If a 40-pound generator applies +1400 inch-pounds to a reference axis, the generator is located

• -35 from the axis.

• +35 from the axis.

• +25 from the axis.

Answer explanation

The distance from the axis is found by dividing the moment by the weight.
1,400 ÷ 40 = 35
Since the moment is positive, the arm will also be positive. The generator is located +35 inches from the axis.

Why is it generally necessary to jack an aircraft indoors for weighing?

• So aircraft may be placed in a level position.

• So that air currents do not destabilize the scales.

• So weighing scales may be calibrated to 0 pounds.

Answer explanation

An aircraft should be weighed indoors to prevent the possibility of air currents moving the aircraft and knocking it off the jacks or causing the scales to give an inaccurate reading.

When determining the empty weight of an aircraft, certificated under current airworthiness standards (14 CFR Part 23), the oil contained in the supply tank is considered

• a part of the empty weight.

• a part of the useful load.

• the same as the fluid contained in the water injection reservoir.

Answer explanation

The empty weight of an aircraft certificated under Part 23 includes a full supply tank of engine oil.

The empty weight of an airplane is determined by

• adding the net weight of each weighing point and multiplying the measured distance to the datum.

• subtracting the tare weight from the scale reading and adding the weight of each weighing point.

• multiplying the measured distance from each weighing point to the datum times the sum of scale reading less the tare weight.

Answer explanation

When an aircraft is to be weighed, it is placed on the scales and chocked to prevent its rolling. The weight of the chocks is called tare weight. The empty weight of the aircraft is found by subtracting the tare weight from the scale readings, to get the net weight. The net weight from each weighing point is added to get the total net weight which is the total empty weight of the aircraft.

Which of the following have an effect on aircraft CG results when conducting a weight and balance check?

• Leaving the parking brake on.

• Leaving the parking brake off.

• Leaving the downlocks installed.

Answer explanation

All of the required equipment must be properly installed, and there should be no equipment installed that is not included in the equipment list.

What is meant by the term "residual fuel"?

• A known amount of fuel left in the tanks, lines, and engine.

• The fuel remaining in the tanks, lines, and engine after draining.

• The fuel remaining in the tank, lines, and engine before draining.

Answer explanation

When weighing an aircraft to determine its empty weight, only the weight of residual (unusable) fuel should be included. Residual fuel is the fluid that will not normally drain out because it is trapped in the fuel lines and tanks.

When making a rearward weight and balance check to determine that the CG will not exceed the rearward limit during extreme conditions, the items of useful load which should be computed at their minimum weights are those located forward of the

• forward CG limit.

• datum.

• rearward CG limit.

Answer explanation

When making a rearward weight and balance check to determine that the loaded CG cannot fall behind the rearward CG limit, you should use the maximum weight of all items of the useful load whose CG is behind the rear limit and the minimum weight for all items that are ahead of the rearward CG limit.

If an aircraft CG is found to be at 24 percent of MAC, that 24 percent is an expression of the

• distance from the TEMAC.

• distance from the LEMAC.

• distance from the Datum.

Answer explanation

When the CG of an aircraft is expressed as a percentage of MAC, its location is determined by finding that percent of MAC (the distance between the LEMAC and the TEMAC). The CG is located at this distance measured from the LEMAC.