Physics problem
 

I Have a question. I have been pondering over the equation L=1/2 VSC. I am looking for the minimal wing area required to lift a 400 pound object. But for that I would need to know the lift required to raise that object 20 ft. Could someone help me in my resoning?

RE: Physics problem
 

Because "lift" is a function of three factors -

Wing area
Airfoil characteristics (shape, camber, angle of attack)
Speed (strictly velocity)

you can take your pick out of each of these to answer your question. To illustrate...

If you have a large wing area, the speed required to lift your 400 lb object will be slower. If you have a small wing area, the speed required will be greater.

The airfoil that you choose will have to be efficient within the speed "envelope" that you choose.

The airfoil/wingarea/speed will also determine the landing and takeoff speed required.

So a simple question with no simple answer.

RE: Physics problem
 

What do you mean by "lift"?
Take off from the ground?
Any distance restriction for the takeoff?
Launch from a dolly?
Drop from a flying airplane?
The requirements are too vague for a definitive answer.

RE: Physics problem
 

What I meant by lift is this. The lift needed to lift the 400 lb object at takeoff. The lift needed to maintain an altitude of 20 ft. travling at 20 mph. and the lift needed to land. I should have been more clear.

RE: Physics problem
 

You want to lift 400 lbs at 20 mph?

If the max lift coefficient is 1.5, you will need 260 sq ft of wing surface. The aspect ratio will largely determine the power required to overcome induced drag. For example, with AR = 5, induced drag at takeoff will be ~40 lbs. You'll need at least that much thrust at 20 mph (not static) if the plane is to climb.