The ISA
- assumes a sea level temperature of 25 degrees C.
- is referenced from the equator.
- is taken from 45 degrees latitude.
Explanation from PART66Online
The International Standard Atmosphere is referenced to conditions at 45 degrees latitude, giving the agreed baseline of 15 degrees C, 1013.25 hPa and a 1.98 degrees C per 1000 ft lapse rate at mean sea level. It is not referenced from the equator, where surface conditions are warmer, and its sea level temperature is 15 degrees C, not 25 degrees C.
K
Kaszimi asked · 14 Apr 2026
can someone explain?
Community Comments (1)
A
Alex772
16 Apr 2026
I think A. defines a standard atmosphere model.
it is correct.
it is correct.
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