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Old 2nd April 2005 | 20:24
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R1Tamer
 
Joined: Nov 2004
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From: USA & UK
Pack2

Afraid I can't resolve or agree with your logic. This question is predominantly talking about temperature variations and their effect on true altitude - not pressure i.e lower datum variations and there effect on pressure levels.

For example:- imagine you could sit on top of a 10000' metal rule calibrated and graduated to be accurate at all parts only in ISA temperatures and the lower end was set at sea level. If the ruler is allowed to cool down below the calibration temp it will no longer truly be 10000' long since contraction will have caused it to shrink. It will still display ten thousand feet written at the upper end but it won't be ten thousand feet long. i.e. it is over-reading its true length.

Never in these circumstances would it under-read its length?

Hope this helps!

Just a further point that made me chuckle having re-read your earlier response.

What kind of system would it be if the candidate had to read into the question \'what the examiner is getting at\'. Either it\'s a correct fact or it isn\'t - surely it isn\'t an excercise in telepathy.
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