far to the back/ a long way to the back.

It is "arrière". It is like a centre of gravity that is located too far back but in a plane I doubt if you can mention gravity!!!!

One of the reasons for why an aircraft stays aloft is that the center of gravity is located somewhere near the center of lift of the wing. Because the center of gravity is critical to the aircraft's ability to fly, a determination of the aircraft's center of gravity and total weight is necessary, and, required by the FAA, JAR and most other Civil aviation authorities before every take-off. An overloaded or improperly balanced aircraft will require more power and greater fuel consumption to maintain flight, and the stability and controllability will be seriously affected

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In naval architecture, which employs many terms from the field of aviation, a weights and centres study (devis de poids) is carried out to determine where and how weight should distributed across the platform.

Centres are not limited to just gravity. You will also find a centre of bouyancy, flotation, lateral resistance. All of these enter into the equation and form part of the wieghts and centre study.

Whilst what I have set out relates to boats, it seems perfectly logoical that the similar calucaltions must be taken into account in airplane construction. Therefore, the reference to "centre" is not to be interpreted just to mean centre of gravity. There must be a number of different "centres".

In any event, the (short) extract we have, suggests that the centre (no doubt the of gravity, the centre of mass) is too far aft and that upsets the longitudinal trim of the craft and eventually her fore and aft / centreline stability.

One or two quick references relating to aviation :

1 - aviation-safety.net/database/1949/490310-0.htm


2 - www.weighing-systems.com/TechnologyCentre/ aircraftweighing.html

read through the bit on BALANCE, STABILITY, AND CENTER OF GRAVITY