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An aircraft has a total mass of 2 222 kg with a CG of 6.13 m aft of the datum line. After calculations, to return the CG within limits, an additional ballast of 136 kg was loaded. The new CG is at the aft limit of 6.28 m.

• A

2.60 m in front of the datum line.

• B

3.53 m aft of the datum line.

• C

8.73 m aft of the datum line.

• D
8.88 m aft of the datum line.

Mass change / New total mass = Change of CG / Distance from mass to old CG

• Mass change: 136 kg
• New total mass: 2 222 kg + 136 kg = 2 358 kg
• Change of CG: 6.28 – 6.13 = 0.15 m
• Distance from mass to old CG: ?

136 kg / 2 358 kg = 0.15 m / Distance from mass to old CG

Distance from mass to old CG = (0.15 m x 2 358 kg) / 136 kg

Distance from mass to old CG = 2.6 m

=> To move the CG aft, we must add the mass (136 kg) further back from the original position. Therefore, 6.13 m + 2.6 m = 8.73 m.

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• Norway