C of G position

[LDG_GEAR _MONITOR]

Can someone give me a quick reminder - what are the advantages/disatvantages of having the C of G at a forward position and also aft position ?

ta

[the flyingenglishman]

Hiya mate here's a quick summary for you.

A fwd CG gives increased longitudinal static stability and hence reduced manoeuvrability. The fwd CG requires a higher angle of attack to be flown for straight and level flight, causing an increase in both induced drag and trim drag. This increases fuel burn, so reduces range. Climb performance is reduced, aswell as attainable cruise altitude.

For a rearward CG it's just the opposite.

Hope this is what you were looking for,

Flying Englishman.

[High Wing Drifter]

Don't forget that a fwd CoG also increases the stall speed (and visa-versa).

[LDG_GEAR _MONITOR]

just what i was after. i knew one way was better fuel burn - the more i tried to remember and work it out the more confusing it got ! thanks !

[High Wing Drifter]

If you understand why, you'll never be confused again.

Basically a fwd CoG increases the wing loading. As you are probably aware, the CofG is always ahead of the Centre of Lift (CofL) on transport planes. Therefore, the tailplane will need to generate a downforce, to lever the nose up, to maintain straight and level flight. The further forward the CofG, the more downforce is required by the tailplane, therefore the greater the load on the main wing as it has to increase lift (AoA) proportional to the increased tailplane downforce as there is effectively, more weight pressing down on it (wing loading).