Hello team,

The following was a question that was on one of the exams for the performance exam:

An Echo aircraft has a basic empty weight and moment of 1962 kg and 474.8 index units respectively. It is loaded as follows:

Row 1 ....................... 165 kg
Row 2 ....................... 170 kg
Row 3 ....................... 160 kg
Rear compartment ............ 140 kg
Hard ballast is available in the form of 5 kg sand bags.

The minimum amount of ballast fuel that must be carried in the main tanks to keep the aircraft in balance throughout the flight, if no change is made in the existing load, is closest to -

The solution to the question reads the following:

The only compartment that makes sense is the nose, because all of the other compartments are behind the CofG so they would move the CofG back. You don't want that. The nose is empty so the maximum you can add is 30kg.

When I was calculating the answer for this question, I added 55kgs to the nose in line with the CPL workbook "Instructions for use of Echo loading system". When I added 55kgs to the nose as hard ballast, I did not require any fuel ballast.

When 55kgs was added to the nose, these were my calculation:
ZFW weight - 2652. Arm - 2666.82. Moment - 707.24

Can someone help me understand why only 30kgs was added to the nose? I cannot see any limitations that would stop me adding the further 25kgs to the nose also.

TIA.

I've disregarded the maximum zero fuel weight, which I've exceeded. Maximum Zero Fuel Weight = 2630 KG.
I understand now.
Thank you.