Dancing Down the Runway

[Fleet Canuck]

I've just been deleting aircraft that rock from left to right on their main gear while running down the runway. Tim Conrad's Volksplane, Eric Dante's Twin Bonanza, and just today I tried Premier's Robin 160 and it did the same thing. Very good planes, but with a problem that may be unique to my setup, that makes them unsuitable.

I've assumed that a correction would involve trial and error with adjusting contact points in the .cfg file. Is that correct? I'd rather fly than spend time adjusting the aircraft file.

It's always great to get technical help here!

[OBIO]

Are the planes physically bouncing from one tire to the other...or is as shimmy? If the plane is bouncing from one tire to another, then yes contact point tweaks will need to be made. If the plane has a shimmy, then tweaks to the MOI settings in the aircraft.cfg are in order...usually setting them to a lower number will fix the problem.

I'm sure that folks with more understanding of the various parameters involved will chime in and give you a good direction to follow. Me...I know just enough to be dangerous LOL!

OBIO

[srgalahad]

I've just been deleting aircraft that rock from left to right on their main gear while running down the runway. Tim Conrad's Volksplane, Eric Dante's Twin Bonanza, and just today I tried Premier's Robin 160 and it did the same thing. Very good planes, but with a problem that may be unique to my setup, that makes them unsuitable.

I've assumed that a correction would involve trial and error with adjusting contact points in the .cfg file. Is that correct? I'd rather fly than spend time adjusting the aircraft file.

First, it might be worth investigating what's so unique about your setup... although, other than runway surface anomalies, it's hard to imagine something that significant. ( I have flown the Twin Bonanza probably 200 hours, just tried it and can't get it rocking - bobbing slightly on gravel, yes but that's response to the surface)
Second, you don't specify whether this happens at all speeds, or just at one range, nor whether it's on all surfaces and different airports.

While it may be something in the aircraft model, it would be a shame to delete "very good planes" on the assumption that it's a flaw in the model without eliminating other factors first.

[Z-claudius24]

Hi,

Eric Dante's Twin Bonanza

I'm sure this one is not dancing the Samba (or Twist .. choice your taste) by default.
It's must be something special with your terrain or airport ... AFAIK
Dancing occurs on all airports ?

[Fleet Canuck]

Looks like I'll have to reload a couple of these and check the problem more carefully! I think it's just a jitter, more than a bounce, so I guess that is an MOI issue. Empty weight roll MOI I would assume, because the jitter is from left to right. It occurs on default paved runways.

One other very minor thing is I notice some planes will dance on the runway even when stationary when I switch to spot view. Tim Conrad's AA5B Tiger just did that to me yesterday, but that only lasts a second or so. The freeware Cessna 206 does it also.

Of course, another topic would be the viewpoint in VC mode on several aircraft. I have to adjust up and back on several to get a realistic view. I'm sure the developers didn't intend for the view to be so strange, so it seems to be an issue unique to my computer, I assume.

Thanks for the responses. I'll check this out a little more when I get a chance.

[Fleet Canuck]

Thanks for the advice! I reloaded the VP-1 and it was a pitch problem. Reducing the pitch MOI didn't improve it, so I increased the number and it was solved. The touchdown line in Effects also needed to be changed, but that's just excessive tire smoke on landing.

To my embarrassment, I couldn't get the Twin Bonanza to misbehave at all. I don't know what prompted me to delete it. Nice to have it back, and as always, it's great to have a community to get good support. :salute:

One other thing. Prior to joining Sim-Outhouse I was fairly sure the flow of new designs for FS9 had slowed to a trickle. It seemed like the party was over, but being on these forums has introduced me to top notch planes that I never would have found, like the Piel Emeraude (Restauravia) and the Porterfield-Turner CP-65 (I'm in a "low and slow" phase right now), as well as helicopters like the AW-139 and S76 (if only I could fly them in a competent manner...) and also scenery like KPHL. Another big benefit of being here!