Less than 25% CG is considered forward CG. It is forward CG so there is speed increment in Vapp to create higher aerodynamic forces for better handling. ZFW CG as the name signifies is CG without fuel load. MAC TOW is with fuel. This will keep changing towards ZFWCG as fuel is consumed. So to get ideal CG position for landing or for the flight ZFWCG must be in favourable position. This is obtained by proper distribution of cargo and passengers. Incidently the relationship of trim wheel with CG is only for takeoff. Inflight CG is given on Fuel prediction page.
Last edited by vilas; 8th August 2013 at 02:35.