Why doesn't gravity make planes and birds fall out of the sky
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Why doesn't gravity make planes and birds fall out of the sky

[From: ] [author: ] [Date: 11-05-08] [Hit: ]
Here is how you can measure mass in a weightless environment:http://www.youtube.com/watch?v=CI0qqa9T7…Birds and aircraft both rely upon a force called AERODYNAMIC LIFT to support them.In any case, there is a DOWNWASH of air,......

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I'm a scientist-blah blah blah gravity blah blah fuel blah blah blah carbon blah blah blah hope this helps.

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Well...birds and planes DO fall out of the sky if they break.

Injured birds fall like bricks, if they are suddenly injured during flight. Let's hope this doesn't happen.

Same with an aircraft. If the engine suddenly fails, the aircraft becomes a projectile, just like a bullet. Let's hope this doesn't happen either.



"I know that without gravity there is no weight (or mass)"

Correction:
Gravity ISN'T essential for there to exist mass. Mass is MATERIAL.

Mass shows evidence in two important manners. Only one of them is gravitational...the other is inertial.

Here is how you can measure mass in a weightless environment:
http://www.youtube.com/watch?v=CI0qqa9T7…




Birds and aircraft both rely upon a force called AERODYNAMIC LIFT to support them. In any case, there is a DOWNWASH of air, which can indeed be measured at ground level. There is a famous thought experiment called "birds in a truck", which indeed demonstrates this to be true.
http://www.yourdiscovery.com/video/mythb…

In the case of a bird, the bird actively uses its broad wings to push downward on the surrounding air.

In the case of a helicopter, the rotor's tilted geometry pushes downward on air like a propeller does. The entire vehicle tilts forward (controlled by the rear rotor) to get some of the thrust acting both forward and upward.

In the case of a fixed-wing aircraft, the wing's chord line is angled with an angle of attack relative to the aircraft velocity...and the wing deflects oncoming air downward as it flies across that air.


BE VERY SKEPTICAL of any explanation of fixed-wing aircraft lift involving Bernoulli or any "faster air on top" explanation. This usually is based upon oversimplified logic that just seeks to provide a quick explanation, that completely forgets about the restrictions of the Bernoulli equation. In reality, the high and low pressure regions exist for a completely different reason than the Bernoulli equation.
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