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Old 24th April 2001 | 09:24
  #24 (permalink)  
chicken6
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NIMBUS

The only way to get a brick to fly is to provide so much power that the vertical component overrides the weight, and then you might as well call it a helicopter. How exactly were you going to provide this power? Through a jet? A prop? It would only be the upward component of thrust that would get it off the ground unless you had a brick unlike one I've ever seen - one that deflected more air down with the undersurface than it deflected up with the frontal/upper surface.

And parking aircraft outside in horrendously strong winds does create enough lift to flip them over, that's why tiedowns were invented.

Bunyip

The common name for spoilers under the wing is flaps. Different types of flap exist, and can be hinged in different places along the chord, but in general a flap extending from under the aerofoil is called a flap, a flap on top of it is a spoiler, and on the fuselage they are called airbrakes.

Note they are all named after their function, and there is only one called a 'spoiler' because it spoils the lift.

And the boat rudder thing is more to do with the water being 1000kg/m3 whereas air is only about 1.2kg/m3 (at sea level). Being 1000 times more dense, deflecting a certain amount of water is bound to require a much much greater force (then equal and opposite reaction rah rah rah) than the same volume of air. If water was compressible, then we wouldn't even be talking about this because there wouldn't be any dry land on this fair planet.

When I learned all this stuff and could write pages of calculus on the stuff, I seem to remember Bernoulli being pretty well right and Newton being pretty well right, although memories fade with time!

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Confident, cocky, lazy, dead.