F-18C weird behavior
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I’m missing my little dog, … has anyone seen it?
Cheers, :yo:
LS -
Ask Jolly
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Here he is… :mrgreen:
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Now THAT’S goofy…my suspicion would be that if Hornet wing flexure is modeled, there is something wrong with it that gets exhibited with heavy stores loadings.
But I’m also inclined to think the model isn’t that sophisticated…so I’m back to it being just plain goofy…
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Now THAT’S goofy…my suspicion would be that if Hornet wing flexure is modeled, there is something wrong with it that gets exhibited with heavy stores loadings.
But I’m also inclined to think the model isn’t that sophisticated…so I’m back to it being just plain goofy…
yes that’s right
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@Bad:
Know issue with F-18 fm
first time i see it
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Ok…so if it’s a known issue with the Flight Model, then I’m back to thinking there is a condition being violated that should prohibit this from happening when on deck - i.e.; weight on wheels.
…but I’m still left curious as to just what is coded and what isn’t.
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it’s just a bad data for gear amortization
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What is actually looks like (and because it’s noted to happen with heavies) is a problem with this -
https://arc.aiaa.org/doi/10.2514/6.1985-1858
re: Flight Controls - if the problem is in the Flight Model. Don’t know how you guys did/do it, but I’m having a hard time seeing how a gear damping problem ends up in the Flight Model…although I can think of approaches where such could happen, so…
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What is actually looks like (and because it’s noted to happen with heavies) is a problem with this -
https://arc.aiaa.org/doi/10.2514/6.1985-1858
re: Flight Controls - if the problem is in the Flight Model. Don’t know how you guys did/do it, but I’m having a hard time seeing how a gear damping problem ends up in the Flight Model…although I can think of approaches where such could happen, so…
?? you dont understand that gear damping is part of the flight model ?
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Is it safe/possible to take off like this … or does it oscillate out of control?
Is there an easy edit to the *afm file, we can make? (Maybe something for the Fighter Mafia crew to track and distribute?)
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Is it safe/possible to take off like this … or does it oscillate out of control?
Is there an easy edit to the *afm file, we can make? (Maybe something for the Fighter Mafia crew to track and distribute?)
Ask Mav-jp, he knows the afm very very well
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Is it safe/possible to take off like this … or does it oscillate out of control?
Is there an easy edit to the *afm file, we can make? (Maybe something for the Fighter Mafia crew to track and distribute?)
not happening while taking off
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?? you dont understand that gear damping is part of the flight model ?
Not really…it seems to depend on the approach taken to the Flight Model (and/or setting of boundary conditions?). I’ve flown sims where the aircraft seems to literally “fly on the ground” - both X-Plane and the Trainer I fly currently do this, and I can see geear damping being part of that approach - and others where the aircraft seems more stuck/stable to or on the ground plane - i.e.; the BMS Viper, MSFS, Graphsim Hornet 3.0, T-45A Trainer, etc.
What I don’t know is which approach you’ve taken, or if there is any difference in approach between the BMS Viper and Hornet modelling.
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Is it safe/possible to take off like this … or does it oscillate out of control?
Is there an easy edit to the *afm file, we can make? (Maybe something for the Fighter Mafia crew to track and distribute?)
not happening while taking off
My experience has been this “wobbling” issue only occurs at certain speeds. About 1-30…ish kts…and Unfortunately there is no fix that we can make at this time. So as long as you keep the nose pointed strait down the taxiway/runway with rudder pedals below 30 kts you’ll be able to take off.
Also, this issue isn’t as bad on the carrier. It only seems to be this severe on land. So essentially the F-18 in BMS does not have “land-legs”. :mrgreen:
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This doesn’t surprise me in that you spend far less time rolling on the cat, and probably transition through the offending region very quickly.
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Based on my own experience with game physics engines … my guess is there is very specialized code to keep planes glued to the carrier deck as it moves, pitches and rolls. Compared to just rolling along solid ground.
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Possibly…but that doesn’t explain the differences in sims that I see that stick to a ground plane solidly and ones that seem to “fly” along the ground. This was one of the first things I noted about the behavior of X-Plane when I started playing with it. Not to mention that RL Hornet gear are pretty “spongy” - so if the gear are modeled well you should get some spring as the carrier deck pitches and rolls even though you are stuck to the deck…if not chained down. It smacks of different approaches in modelling, to me. I’ve been exposed to a LOT of sims/Trainers over the decades.
Anyway, the “behavior” in the video looks like AOC getting coupled into the aero model when it shouldn’t be - only because RL AOC is only invoked under these types of heavy stores loadings, and nobody has remarked on seeing this with lighter loadings or as SOP with the model…to relate it to the RW. And if the gear model also has a problem I should think that only aggravates things.
Not saying this has to be the case, only what it looks like. I have no idea of the extent of the actual modeling, though I do still believe it’s not as extensive as I’d like to believe it to be.
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Based on my own experience with game physics engines … my guess is there is very specialized code to keep planes glued to the carrier deck as it moves, pitches and rolls. Compared to just rolling along solid ground.
There is no special physics code for carriers it’s the same
This bug is a gear data amortization / stiffness issue
That’s amazing noeone listen to me LOL I created the thing !!