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Old 25th Jul 2011, 01:23
  #643 (permalink)  
Machinbird
 
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Frames of reference

Dutch M
So when doing the Ekin calculations properly, around 3 times more Energy
becomes available for height gain. Note: Speeds only intended for example
purposes, these aren't the actual AF447 figures.
Hi,
I don't really want to discourage an ambitious attack on the AF447 energy question, but let me add a few additional questions to your approach for an answer.

Have you added in the Earth's velocity vector around the Sun? How about the velocity of the solar system around the Milky Way galaxy? The answer should be that it is not necessary, these are negligible factors. For the same reasons, the rotation of the earth does not need to be included (unless you are flying ballistic like an ICBM). It exerts a force on the aircraft all right. We call it Coriolis force, but that too is negligible for our purposes.

There is no absolute inertial frame of reference then, is there? The height gain only reflects the change in position relative to the Earth's center of mass.

Will an aircraft flying 100 knots into a 100 knot head wind be able to convert some of that velocity into altitude gain? Of course it can. (Assuming it can fly slower than 100 knots)
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