Airtimes

a wing flies by accelerating air downward to overcome the weight of the aircraft. it does this by the shape of the wing, and the angle of attack of the wing through the air. engine thrust is used to overcome drag on the airframe. there are a lot of misinformed people who will point to bernoullis princple and use that to explain how a wing flies, but that is wrong. bernoulli was pointing out how to measure drag, and how to approach laminar airflow. you want air to flow smoothly over the top of the wing to limit the amount of aero drag on the wing. as the angle of attack becomes greater, the airflow over the wing separates earlier causing more drag, requiring more power to over come the drag. at some point the engine power out put cant over come the drag on the wing, and the wing stalls, or quits flying. that is where bernoullis principle comes into play. and by the way, if bernoullis principle truly explaned how a wing flies, then there is no way any aircraft could;

1: fly upside down

2: fly at very low speeds.

Technorati Tags: Airflow, Airframe, Airplane Fly, Angle Of Attack, Bernoulli, Bernoullis Principle, Drag On, Engine Thrust, Flies, Fly, Fly 2, Scientific Theory, Shape, Theory Support

Ok im doing a report on airplanes from the small ones to the airliner jets and was wondering what exactly it means when a plane stalls. Also are there different type of stalls, and do pilots stall on purpose? And finally can you recover from a stall once it happens?

A stall is when the angle of attack, the angle at which the wings meet the onrushing air, is exceeded and the wings lose lift causing the plane to drop. The angle of attack at which this happens can vary depending upon the airspeed. Sufficient flow of air must continue over the wings to maintain lift. A stall can occur very basically speaking when one of two things may happen:
Too steep an angle of attack with insufficient flow of air over the wings causing a stall or
Insufficient airspeed at any angle, again not enough airflow over the wings.
A stall can be easily recovered from providing you have sufficient space between you and anything hard underneath you (like ground).
Pilots are trained to induce stalls thereby learning to recover from them.

Technorati Tags: Airflow, airplanes, Airspeed, Angle Of Attack, Ground Pilots, jets, Sufficient Space, Wings