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Refer to figure.
Information about the take-off data can be found in the attached figure.

If the flight time is 1.5 hours and the estimated fuel flow is 900 litres per hour (fuel density = 0.79 kg/l) and "Freight 1+2" will be dropped during flight within the scope of a rescue action, what will be the CG position at landing?

• A
19 cm in front of datum
• B
19 cm aft of datum
• C
20 cm aft of datum
• D
18 cm aft of datum

To Calculate the CG at landing we need to calculate the mass at landing and moment:

Landing mass will be equal to takeoff mass minus fuel burned in 1.5 hours flight and freights number 1+2 as they will be dropped in the flight.

Fuel volume burned in 1.5 hours = 1.5 x 900 = 1350 L
Fuel mass burned in 1.5 hours = 1350 x 0.79 = 1067 kg
Fuel mass on landing = 7120 - 1067 = 6053 kg
Fuel moment on landing = 6053 x (-9) = -54477

Landing mass = 11048 + 155 + 6054 = 17256 kg
Moment in landing = 386680 — 26350 — 54477 = 305853

CG on landing = 305853 / 17257 = 17.72 cm aft of the datum
Closest option: 18 cm aft of the datum

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