# Can the center of gravity ever fall outside the mean aerodynamic chord?

Can the aircraft center of gravity be outside the mean aerodynamic chord (i.e. %MAC being negative or more than 100%), at least theoretically?

I'm not an expert in aviation. All I've heard is the safe CG range on nearly all aircraft lies between 10 and 50% MAC.

## 2 Answers

Yes it can be. Whether the aircraft can fly with the centre of gravity outside this range is a different matter altogether.

When flying, the aircraft is balanced around the centre of gravity of the aircraft. Aerodynamic forces from the wing and the tail provide the balance, but up to a maximum. At some point the aerodynamic lift capacity of the tail is saturated.

In order to make sure that the balance can be achieved, the centre of aerodynamic force must be within certain limits of the centre of gravity. Or the other way around: CoG must be within certain limits of centre of lift, which is the better way to define it, making the CoG the variable.

Yes, canards have a center of gravity outside the chord.

• A one liner without explanation and an image is not a good answer. Furthermore I don't agree that it's right the way it is currently written, what I think you mean is an aircraft with a canard configuration can have a CG outside the MAC. Though even then, the fact it has canards isn't what actually allows it to have the CG outside the MAC, it's a combination of design factors. – Notts90 is off to codidact.org Jun 2 '17 at 6:37