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The simple answer is that a wing moves through the air generally at a non-zero angle of attack. The air flow below the wing sort of impacts the wing surface, compressing and slowing down as it is deflected. See this Drawing:

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If you mean what I think you mean, then your idea won't work as well as you're hoping. Let me illustrate with a rhetorical question: Would you sky dive with a helicopter rotor as your parachute? I certainly hope you wouldn't. Upon brief reflection, you will see that your "propeller-chute" would not provide very much drag as you hurtled groundward. As a ...

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There's a more straightforward calculation. In order to travel eastward, the plane's velocity must have a southward component of 60kph to cancel the wind from the south. Since the plane's speed is 100kph, we have the eastward component (in kph) is just: $$v_E = \sqrt{100^2 - 60^2} = 80$$ Thus, you are correct; the time required to travel 189km eastward ...

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