Viper wobbling at high speeds

[eurybaric]

As the title says, the plane starts going all over the place at around 700+ knots. I know it’s not a major issue since you rarely need/want to get to those speeds but still. If I’m in cockpit view and it starts doing that, switching to external makes it stop. So that makes me think it’s not intended behavior of the flcs, aerodynamics, or something. Is it fps related? Computer performance in other words?

Again, this is not a major issue, just want to see if it’s just me or everyone else too.

Cheers!

P.S: I’ll do a proper report with repeatable steps if it’s an otherwise unknown bug.

[Red Dog]

i doubt it’s a bug but intended
700 kts is pretty fast, most of your stores will be off limits there as they 're most likely in the 550-600kts limits

[Dee-Jay]

Articles. https://www.benchmarksims.org/forum/content.php?141-The-New-Funky-Chicken

[Hornet]

@eurybaric:

switching to external makes it stop

Thats a point. Why would it stop in external views? Just a coincidence?

[Red Dog]

because you’re not in the airplane feeling it …. ?

[TommyGun]

To the thread author: at what altitude did it happen? What payload did your aircraft carry then?

[eurybaric]

Any altitude, clean bird. And as hornet mentionned, if it was intended why would it stop when I switch to external? The plane, not the view, wobbles. It gets into what feels like a positive accelerating adjustment loop, i.e. It exceedingly corrects for stable flight. I’m at work now (bms priority haha) so can’t do a proper test just now buy I will as soon as I get home (a few hours).bits definitely repeatable. If you have suggestions for specific parameters I should test (stores, etc) let me know and I will do those as well.
Cheers!

[eurybaric]

Dee-Jay it’s definitely not LCO. Also what a coincidence im djaying right now

[TommyGun]

Thank you very much for your reply, eurybaric. Not hard to guess, I asked with an intention of reproducing the situation. I myself am curious enough, since I rarely, if ever, fly at speeds exceeding 700 knots.

[Dee-Jay]

@eurybaric:

… im djaying right now

Have fun

Waiting for your report and/or video capture.

[eurybaric]

Alright so:

Clean bird
17000ft msl
wobble starts at around 780 kts.

I pull up to around 34500 ft
wobble starts at around the mach 2 mark.

ACMI file (zipped): https://drive.google.com/file/d/0BxGt58vi1AeFZGQ2Ul9xMWNPcFE/view?usp=sharing

–—

Awesome music Dee-Jay it’s the soundtrack of my night now. And oooh that flanger haha!! :bdance:

EDIT: Forgot to say that when the wobble goes down and stops that’s cause I switched to external view. Cheers!

[Amraam]

Mach 2? Is way too high, seems legit near the overspeed.

[eurybaric]

Agreed, totally! As I said I’m sort of nitpicking here but the reason I brought it up is that I suspect I’ve hit a limit in BMS, not the aircraft. Maybe.

[Amraam]

BTW, just curious about something, what is your fps?

[Stubbies2003]

This sounds like the exact problem I had to tame awhile ago. Nothing to do with external stores or massive overspeed as I can get this to happen at less than 800 knots at much lower altitude so that mach is only around 1.15 or so. Guessing my system was giving it too much performance as I had to enable v-sync on the newer drivers/cards in BMS to tame that mess. Another odd bit about this was with the newer drivers/cards and v-sync off I could only duplicate this when flying over water. Flying over the peninsula removed the problem.

100% duplicatable as many times as I wanted to. I posted on this a few times and made videos about it. Don’t assume people are messing up and not understanding LCOs as that isn’t necessarily the case in BMS and hasn’t been for a LONG time as this problem is long in the tooth.

Here is the link to my initial posting under another poster covering this subject in detail.

https://www.benchmarksims.org/forum/showthread.php?14469-Aircraft-shakes-along-roll-axes-when-traveling-above-Mach&highlight=funky