"Matt Whiting" wrote in message
...
Mike Rapoport wrote:

"Andrew Sarangan" wrote in message
om...

Please explain how 2C/1000 is used in altimeter calibration. I did not
know altimeters had any temperature corrections.


Altimeters are preasure guages with a scale in feet. They assume a
pressure lapse rate with altitude and the pressure lapse rate that they
use is ISA whch assumes 15C at SL and 2C/1000'.

Last I knew C was a unit of temperature, not pressure.

Matt


Last I heard temperature had an effect on the density of any gas with the
consequent lowering (in feet) of any preasure level with decreasing
temperature. Remember "high to low, lookout below". Canada even has
altitude correction tables for use when temps are very low.

What is the pressure at 1000' MSL at -50C? How about at +50C?

Mike
MU-2