W = L*cos(climb angle) + T*sin(climb angle) - D*sin(climb angle)
Climbing means thrust will no longer equal drag in a steady state. Hence, part of the weight is being carried by the thrust of the engines and lift will in fact decrease.
It is easier looking at in in a coordinate system fixed to the velocity vector. Assuming thrust to remain parallell to the direction of flight, the steady state equation perpendicular to the direction of flight:
L = W*cos(climb angle)
And again, we see that lift decrases with increased climb angle.
Or, for a more intuitive approach, analyse the extremes. Assume the climb angle to approach the vertical. Lift will go to zero. It thus makes sense to assume that lift will in fact decrease with increasing angle of climb.
Last edited by ft; 16th October 2008 at 19:18.
Reason: Grammatical blooper