[ACE-OF-ACES]

1) Has engine underheat been disbaled in v5? (I can't get this to happen with a cold start either with or without the Expert mod).

Not sure did not hear anything about them diabling it

2) Is Expert mod only for net play?

No you can use it offline too

3) Can you get the new FMs without using the Expert Mod?

Yes and no

The new FMs for the mod planes (new slot) listed are allways active, where as the new FMs for the stock planes (orginal slot aka Oleg's) listed are only active when EXPERT mod is enabled

HSFX is different from other mods and mod packs in that the HSFX team has an actual aerospace engineer (Aaken) with a Ph.D. doing their flight model (FM), which is why the new EXPERT MODE flight models are so good. Not since the days of Oleg himself has someone with his background and education done flight models for IL-2

Also know that Aaken used very conservative performance data (static) for the US planes, most of which came from Americas Hundred Thousand, Thus you may see a little less speed and ROC for some planes, that you can see in IL-2 Compare for HSFX.

IL-2CompHSFX.zip

The following is the read me is provided here separately but is also included as part of the download.

IL-2CompHSFX_Read_Me.pdf

But Aaken's real focus was on making the planes 'FEEL' right. He spent a long time looking at the limitations of the IL-2 6DOF flight model and made changes to the FM (FMD files) to account for the limitations to improve the over all 'FEEL' and 'PERFORMANCE'. In the initial HSFX 5.0 release his focus was on the 'key' ETO planes, his next update will focus on the PTO planes.