TAS

caliginousface

Frank N. Beans
So in some publications, True Airspeed is defined as

1) "CAS or EAS corrected for non standard temperature."

In others...
2)"CAS or EAS corrected for non standard temperature and pressure."

OR
3)"CAS or EAS corrected for non standard temperature and pressure altitude."

So the last one makes the most sense to me, in that you're using pressure altitude and temperature to calculate TAS and not so much an altimeter setting. But technically, you are using the altimeter setting to find pressure altitude, so does this make #2 AND #3, above, correct?

Today I figured TAS only considered temperature and not altimeter setting, thus making #1 and #3 the only correct answers. Somehow I glazed over the fact ambient pressure is used to determine pressure altitude.

So I guess I just answered my own discush.

:crazy:
 

MidlifeFlyer

Well-Known Member
Somehow I glazed over the fact ambient pressure is used to determine pressure altitude.
Hmm. Kinda hard to glaze over that. :D

(although I'm not sure you said it the way you mean - "pressure altitude" assumes standard pressure which is why ambient pressure is used as a correction factor for "true" calculations.)
 

caliginousface

Frank N. Beans
Hmm. Kinda hard to glaze over that. :D

(although I'm not sure you said it the way you mean - "pressure altitude" assumes standard pressure which is why ambient pressure is used as a correction factor for "true" calculations.)
Right I meant used to correct for true.

:crazy:
 

tgrayson

New Member
So in some publications, True Airspeed is defined as
More intuitive, in my view, is to understand that the difference between EAS and TAS is a non-sea level air density. Then the factors that affect air density are easy to remember....temperature and pressure. If you could measure density directly, you wouldn't need temperature and pressure.
 
Top