I have a problem with the outside air temprature (OAT). Whenever flying the OAT rises up to about 15° at FL100-150 and then goes down again.I'm not sure if this is a problem with the NGX systems which are showing the temprature to me or with ASE which is actually inserting the weather into FSX.I only know that this is surely not realistic and so any help regarding this issue would be greatly apprechiated.

Emanuel,If you are flying online and using either SB or FSInn please ensure that all weather-related setttings within those programs have been disabled. If you are using a saved flight from within FSX please ensure there are no conflicts with weather depiction by clearing all weather through your FSUIPC interface. JW

thanks for your answer Jeffrey. I'm indeed flying online with Squawkbox and all those failures accoured only when flying online (at least I've only watched on that online). I'll check my settings tomorrow.Thanks for your help and have a nice cristmas evening.

Are you definitely talking about OAT, or is it possible that you are just reading the TAT readout?TAT rises with airspeed, and your acceleration might be big enough to make the temperature rise in climb over FL100, although I am not sure if 15C is possible.Do a little experiment, fly in default clear weather to FL100-120 and compare TAT readouts in whole speed range. That could be as much as 100-330kts band easily. You will see TAT change quite a bit there.

Are you definitely talking about OAT, or is it possible that you are just reading the TAT readout?TAT rises with airspeed, and your acceleration might be big enough to make the temperature rise in climb over FL100, although I am not sure if 15C is possible.Do a little experiment, fly in default clear weather to FL100-120 and compare TAT readouts in whole speed range. That could be as much as 100-330kts band easily. You will see TAT change quite a bit there.

A TAT of +15c in the 10,000 to 15,000 foot range would not be at all unusual, especially once the aircraft begins its acceleration from 250 knots at 10,000 feet. I rode jump seat on a GIV maintenance test flight recently where the TAT was showing +5c at 19,000 feet, with an actual static temperature of -18c. This was at 330 knots IAS.

thanks for confirmation Jim.

Little rule of thumb,An easy way of converting TAT to SAT is divide your IAS by 10 and this figure added to your TAT is your SAT (as a minus value).e.g IAS 290kts, TAT -11290 divided by 10 = 2929 + 11 (TAT) = -40 SAT.Not super accurate but a an easy guestimate

Edited January 10, 201214 yr by Twistgrip