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Does aircraft weight affect lift?
The motion of the airplane through the air depends on the relative strength and direction of the forces shown above. Some external source of power has to be applied to initiate the motion necessary for the wings to produce lift. But during flight, the weight is opposed by both lift and drag.
Why does sweep reduce lift?
A swept wing typically angles backward from its root rather than forwards. Because wings are made as light as possible, they tend to flex under load. Backwards sweep causes the tips to reduce their angle of attack as they bend, reducing their lift and limiting the effect.
How does downwash affect the lift coefficient of a wing?
For three dimensional wings, the downwash generated near the wing tips reduces the overall lift coefficient of the wing. The lift coefficient also contains the effects of air viscosity and compressibility.
How is the lift coefficient used in aerodynamics?
The lift coefficient is a number that aerodynamicists use to model all of the complex dependencies of shape, inclination, and some flow conditions on lift. This equation is simply a rearrangement of the lift equation where we solve for the lift coefficient in terms of the other variables.
What are the lift requirements of a plane?
• High lift requirements (takeoff and landing) • Cruise Mach number • Buffet-free high altitude flight • Low wing weight • High wing stiffness • Sufficient fuel volume in the wing • Wing parameters: • relative thickness
At higher speeds, it becomes important to match Mach numbers between the two cases. Mach number is the ratio of the velocity to the speed of sound. So it is completely incorrect to measure a lift coefficient at some low speed (say 200 mph) and apply that lift coefficient at twice the speed of sound (approximately 1,400 mph, Mach = 2.0).