I don’t know exactly when this started, probably around SU15, but I seems to have unrealistically high temperatures on high altitudes with Live Weather turned on. For example I am now out on the The Pacific Ocean at N41W150 at cruise FL380 and I have TAT at -18c in the 787. This seems way to high f…

Don’t confuse True Air Temp (TAT) with Static Air Temp (SAT). TAT takes compression into account. From https://www.flyingmag.com/air-temperature-explained/ : “Total air temperature is the SAT (actual OAT) plus the temperature rise associated with high-speed flight. This temperature increase is cal…

Do not re-install anything. This is a sim issue and have seen it on many systems. Since our 777 release, we have had reports of people running out of fuel, and it took us a while to realize it was due to the temperature issue. I have seen +2C at FL290 myself. Mathijs Kok PMDG

Spot on, thanks! It is of course TAT shown in the 787 and I fly M.84 so I guess a 30c+ increase from SAT (-52c) it exactly as you would expect. I mixed up the TAT with OAT, should have looked it up a bit better :slight_smile: Edit: so @MikeB54331 ’s explanation then explains what I see in the 787 …

[image] InboardPrism4: @TheFalconOne do you have any rule of thumb to how to calculate the extra fuel needed for the PMDG 777 to avoid running out of fuel on a long haul? Impossible to say. If you calculate with -50c and you get +2c you burn a lot more fuel.

I’m doing a long haul flight at the moment of 6,300nm. Over the pacific I’m seeing what I’d expect, TAT at -20 (the compressed air temp) and -50 for SAT. And fuel at +3 deg C: [WhatsApp Image 2024-07-26 at 15.52.41_b266c1a4] I suspect its the plane itself rather than the sim.

I don’t know if anyone else is still having this issue or if there’s a known fix, but I am occasionally experiencing very high TAT temperatures at altitude using live weather, like +30c at 33,000 feet. This happens in a number of payware jetliners including PMDG and INI. I don’t really fly the defau…