Hi
In the custom weather setting of the latest version of MFS comes the term “Temperature MSL/ISA+10°”.
I know the definition of the standard atmosphere ISA, but I am not sure if I am correct with my assumptions. I think it concerns the calculation of the true altitude (TA).
Example: LSZS Height=5000 feet, Temp = -4°
ISA for 5000ft = +5°C (ISA Curve)
Delta ISA = 9°C
4 ft per 1000 * 5 * 9 = 180 feet.
The true altitude = 4820 feet
The second term is the “Pressure”. I think this is the QNH from ATIS
If the QNH isnt 1013 there is an additional correction of 27 feet per 1 hPa
Is this correct ?
For which calculations the program use the Delta ISA of 9°C?
For TA?
Thanks for help