PPRuNe Forums - View Single Post - Altimeter reading temperature correction

15th August 2003 | 08:55

#3 (permalink)

compressor stall

Joined: Feb 2000

Posts: 4,704

Likes: 589

From: 500 miles from Chaikhosi, Yogistan

+/- 4 X ISAD X (alt/1000)

eg: for an approach in -10deg temps with an OM height of 1500 feet:

-4*-25*1.5=150ft OVERREAD.

Or do is I do, ditch the minus signs, just use 4*isad*alt/1000 and remember that colder will overread/warmer will underread.

So, to answer your question:

4*40*1.76=281

so on outermarker crossing, your altimeter should indicate 2040'.

Thank ChimbuChuckles for teaching me that one!

**Edited to correct ISAd due to the effects of no sleep**

Last edited by compressor stall; 16th August 2003 at 04:52.