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How does one explain lift without downwash
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You can't have lift without downwash. If you are able to produce lift without downwash you have your fortune made, helicopter manufacturers for one will beat a path to your door. A couple of examples I hope may illustrate.
Example 1 Consider the fin/rudder of an aircraft flying without any induced sideslip from other causes. The rudder will be faired with the fin (0° deflection) and the angle of attack is zero. In this condintion we have a symetrical airfoil and on either side of the fin/rudder will be a pressure field induced by the airlow being accelerated over the curved surface. The pressure fields on either side of the fin/rudder are equal and are thus unable to effect any turning of the airflow to create a downwash. The instant rudder is applied a positive angle of attack is created which then creates an imbalance in the pressure field on either side of the fin/rudder. The imbalance in the pressure field causes downwash and so you then have lift. You may have seen the computer modelling of the pressure fields about an aircraft where the pressure level is depicted by different colours. An aircraft experiences pressures of varying levels on all external surfaces, but unless there is an ability of the pressure field to induce a downwash there is no lift.
Example 2 A propellor is nothing but a wing that rotates, rather than travelling through the air in a straight line as does an aircrafts wing (for all intense purposes). As a pilot you intuitively know that unless the propellor is blowing air back you have no thrust. Thrust and lift are exactly the same and is the result of an airfoils movement through the air at an angle of attack sufficient to induce downwash, thrust being the lift produced by a propellor, and lift the thrust produced by a wing. In the propellors case the downwash is seen as a cylinder of air being thrown to the rear, and in the wings case, as a mass of air being thrown towards the ground.
As kids we used to live on a small hill directly under the approach path. The heaviest aircraft we used to see was the DC-3 and they would pass over the top at a couple of hundred feet. On a calm day a party trick with school mates was to place a sheet of newspaper on the ground and shortly after the -3 passing over the paper would move as if by an invisible hand.