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8. Basic aerodynamics

The ISA

  • defines a standard atmosphere model.
  • 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 it is a fixed standard rather than the live atmosphere.

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.

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