What you are talking about here is a air volume issue, and is part of certification.
It is not part of the question. As I stated JAR-OPS 1 Subpart G (Performance Class A) states all the items you need to tick off for a valid take-off performance calculation. There is clearly talks about ambient temperature, but does not mention how this ambient temperature needs to be measured.
We have been keeping track of ATIS temperature versus SAT (a very accurate temperature measurement. It comes from the aspirated TAT probe and is therefore corrected for reflective heat from the ground). Here we are seeing difference ranging from 0 to 2 degrees. Most of the time on the upside (SAT being higher than ATIS temperature). We are trying to find the reason behind this. I know at the stations I have visited in the less developed world, the temperature sensors are at a height of 10 meter or greater. At my home base all ten temperature sensors are at a height of 1.5 meters. I am using pprune to see if someone knows what the rules are for measuring ambient temperature at an aerodrome. Anyone that can help me out with this, thanks!
Greetings O.