Glad to find out that it runs in Proton now, no critical problems.
With launch options:
PROTON_USE_DXVK=1 WINEDLLOVERRIDES="d3d10=n;d3d10_1=n" %command%

Yes.. this game is very old but it means it is also very cheap and it is also very easy to run on any modern computer. I wasn't sure if flying sims are for me so this is a great way to try it out. I`m loving this. I don't care about the graphics I care about getting a true sense of what feels like to fly a plane and this game is achieving that.

Even at 80% off, this relic is a loading screen simulator

I bought this during the Winter Sale for just 4.99€ (-80% off) thinking "hey, it's a classic flight sim, can't go wrong at that price." Boy, was I wrong. This game is a time capsule from 2006, and not in a good way.
The loading times are absolutely horrendous – we're talking 5-10 minutes just to get into a flight, even on an SSD. It's like the game is buffering the entire history of aviation before letting you touch the controls.
The menus and graphics? Completely outdated. The UI looks like it was designed in MS Paint by someone who hates usability, and the visuals are blurry, low-res mush that makes modern freeware look cutting-edge. Textures pop in and out like they're allergic to your GPU.
And don't get me started on the tutorial voiceover. The speaker sounds like a Google Translate fever dream – robotic, emotionless, and rattling off lines in a monotonous drone that could put an insomniac to sleep. "Turn left rudder... apply power... climb to altitude..." Zzzzz.
Even at that rock-bottom sale price, this is way too expensive. Save your money and time – fly a paper plane instead.
Not Recommended