Don't mean to necro this post, but I'm having the same problems as all of you.
I noticed that this became a problem with the F-18 specifically.
I have a really good computer rig and my VR (Rift) works flawlessly with the other planes I own (F-15, AV8b, Su-33 etc etc), granted, the F-15 model and Su-33 really aren't high detailed as the F-18, but the AV8b Harrier is really good and probably on par with the Hornet. The difference is that I never, ever, go below 45 fps or 90 in the air in VR with the Harrier. Does not matter if I'm on the ground looking at all the other static planes or flying between buildings in the PG map with other planes, it's flawless, even with OBS on streaming, I never lose a frame.
So why this is such an issue with the F-18 kinda bothers me since I thought it would perform as good as the Harrier with my VR setup. It's not close. I at least figured out that the big problems is with the static F-18 next to me, because every time I look at them, my frames crashes into oblivion. I hope this issue gets the love it deserve.