View Full Version : Temperature error correction
gibr monkey
2nd Nov 2011, 11:34
Has anybody got a chart or know where I can a chart from the internet for Temperature error correction?
seilfly
2nd Nov 2011, 11:44
Table III-1-4-1 b) on page III-1-4-5 in PANS-OPS vol 1
(Link to PANS-OPS vol 1 (http://dcaa.slv.dk:8000/icaodocs/Doc%208168%20-%20Aircraft%20Operations/Volume%201%20Flight%20Procedures,%205th%20ed..pdf)
alphacentauri
2nd Nov 2011, 21:23
We publish 2 tables in the front of our departure and approach procedures here in Oz
Airservices Australia AIS - DAP 129 - Legend, General Info and Tables (http://www.airservicesaustralia.com/aip/pending/dap/LegendInfoTablesTOC.htm)
See the tables 2 and 3, they are both the same but one is used for initial approach altitudes and the other is a bit more accurate and used for MDA adjustments.
Cheers
Alpha :ok:
reynoldsno1
3rd Nov 2011, 02:38
Rule of thumb is 4ft per 1000ft above AD per AD temp degree of difference from ISA
i.e. AD @ 1000ft amsl @ 0C w/FAP at 3000ft alt
FAP height = 2000ft
AD ISA temp = 13C, so difference from ISA = -13
Temp error = 4 x 2 x 13 = -104ft (underread)
ColdCalc
3rd Nov 2011, 03:04
Several complaints suggest that your post is in the vein of free advertising. If you wish to advertise your product, by all means organise that through the system. JT
SFI145
3rd Nov 2011, 03:28
@reynoldsno1
Surely that example is an over-reading ie 104 ft has to be subtracted from the indicated altitude to get the true altitude?
reynoldsno1
3rd Nov 2011, 23:48
Sorry - you're quite right ... I've been working with high temperature figures too much recently!!
b737NGyyc
4th Nov 2011, 04:28
This table is a little easier to use than the graphs in previous links.
RAC - 9.0 INSTRUMENT ARRIVAL FLIGHT RULES (IFR) ? ARRIVAL PROCEDURES - Transport Canada (http://www.tc.gc.ca/eng/civilaviation/publications/tp14371-rac-9-0-2604.htm#9-17-1)
Look at figure 9.1.
This is what our regulator here in Canada publishes and I have to say we are pretty used to cold temps here.
Checkboard
4th Nov 2011, 09:12
Or you can work it out on your Jeppesen CR-5:
http://www.stefanv.com/aviation/flight_computers/cr.jpg
.... you DO carry one, don't you? ;)
Yes, but where's the LNAV/VNAV/Autotrim selector?:D
main_dog
4th Nov 2011, 10:10
The one I use is that the altimeter will be off by 4% for every 10º off ISA. Obviously if it's cold the altimeter will overread (ie it will be "dangerous") and if it's warm it will be "conservative" (ie underread).
So for a simple example if the published OM crossing height is 1000' at a sea level airport, and the OAT is -5° (ISA minus 20), you can expect the altimeter to overread by 8% (so 1080' at the OM.)
MD