# How can the lift force be changed without changing velocity?

I am facing a problem for calculating the 4 forces affecting the aircraft balance. Suppose the following inputs:
Aircraft velocity is 222 m/s.
Aircraft mass is 23500 kg.
Aircraft weight is 227360 kg.m/s2
At zero angle of attack the lift coefficient is 0.2 By Calculating the lift force from one wing 172899 N.
for the two wings lift force *2 = 345799.125 N

The problem is:
Now I want the aircraft to go to balance state to move with constant velocity.
So all the four forces should equals to zero thus the lift force should equlas the weight force.
How Can I decrease the lift force?

Assuming:
I still need the aircraft to move with constant velocity 222 m/s.
The lift is affected by angle of attack which is zero.
The air density is constant.

how can I the aircraft balanced with velocity 222 m/s?
Can I decrease the lift force without affecting the velocity?

• "How Can I decrease the lift force?" Typically when flying this is done by lowering the AoA until lift=weight and the aircraft holds altitude. I would think that you would want to pick an AoA to be the lowest drag at your cruise speed, which will give you the highest velocity for the least amount of power. – Ron Beyer Oct 24 '16 at 13:24
• Thanks very much. I don't know that small decrease in the AOA will make this big difference in the lift force. – Ahmed Elhamy Oct 24 '16 at 14:16
• The coefficient of lift increases by about 0.1 or a bit more per degree. – Jan Hudec Oct 24 '16 at 20:42
• Is your airplane a biplane? Then the total lift will not be double due to interference. If it's a normal monoplane, it has only one wing, left and right halves. Moreover, lift calculation normally involves the full wing area, which usually even includes the part occupied by fuselage. Rarely do we use half wing area for anything. I mean, people do say "left wing", but when you are so exact with your numbers and units, you want to be precise with the terminology ;) – Zeus Oct 25 '16 at 2:38