Exactly how much lift is needed to overcome the weight of an average person?

I am designing a "glider" of sorts, and I have some basic questions about the physics involved to get me started. How much lift is required to overcome the weight of an average person, say 150 pounds? Is the lift required simply 150 pounds?

• Also note that lift is quite diffecult to calculate, since it depends on the shape of the air-foil, air speed and angle of attack. And to be able to fly you also need to be able to maneuver, for example gain height. So your lift should also be able to exceed your weight (often by increasing the angle of attack, which also increases the drag). Dec 27, 2013 at 4:11
• Aircraft have a rating - wing loading - expressed in weight per unit area. A typical small plane is in the range of 10lb/square foot, which is achieved at a speed of roughly 60 mph. Lift is proportional to speed squared, so if you halve the speed, you need 4 times as much area. Dec 28, 2013 at 17:58

• To be picky: "pound" is a word for a unit of mass and for a unit of force. An object with a mass of 1 pound will have a force of gravity of 1 pound acting on it on earth. Which means that if you try to use both of these units together, $F=ma$ doesn't work any more. Check out "slug" and "poundal", or stick with SI. Dec 27, 2013 at 18:40
• There are several ancient, coherent versions of the Imperial system of units. One used pounds mass and poundals force. Another used slugs for mass, and pounds for force. As long as you stayed in one or the other, $F=ma$, with $a$ in $feet/second^2$ Dec 27, 2013 at 21:00