Jim Wilson wrote
> Vivian Meazza <[EMAIL PROTECTED]> said: > > > > > > > Martin wrote: > > > > > > David Megginson <[EMAIL PROTECTED]> wrote: > > > > Update of /var/cvs/FlightGear-0.9/data/Aircraft/pa28-161 > > > > In directory baron:/tmp/cvs-serv12589 > > > > > > > Modified Files: > > > > pa28-161-yasim-set.xml > > > > Log Message: > > > > Change camera position so that model doesn't rotate around the > > > > nose. > > > > > > I can't withstand the impression that changing the _camera_ > > > position didn't lead to the intended success. Take a simple > > > stick and rotate it around one of its ends. For an observer > > > the phenomenon is still the same even when he changes his > > > viewpoint. If you want to rotate the stick around its middle > > > you really have to change the centre of rotation which means, > > > that one end of the stick goes up and the other end goes down. > > > > > > At least in the _outside_ views the PA-28 still rotates > > > around its nose after the recent changes, > > > > > > > We've been here before haven't we? In developing the Hunter model I > > first put the model origin at the nose to conform to the > YASIM origin, > > but the model then rotated about the nose - most disconcerting in > > outside views! I moved the model (not the YASIM) origin to > the CofG - > > the model behaves nicely in all views. It's not strictly correct on > > the ground, because the model has differential braking, and should > > more or less rotate around the braked wheel, but you would have to > > have a very sharp eye to spot the deliberate :-) mistake. > > > > If you put the model back to the nose and use the method that > the p51d and the pa28-161 use (the target offset) you'll look > better on the ground. Tried that. Looks just the same to me. As I said some time ago: yer pays yer money and yer takes yer choice. Neither is right on the ground for differential braking: with one brake full on the aircraft more or less rotates around that wheel. The model doesn't! When the aircraft is moving the forward the CofG should rotate about some point outboard of the braked wheel. All to do with tyre slip angles, but I'm not sure if the FDM's know about those, and I would need to consult my race engineering handbooks. But, hey, we're building flight simulator, not a ground handling simulator. If it's good enough that'll do me. PS why in an external view does the Hunter appear to do an upward roll in the up leg of a loop. And a downward roll in the down leg? And why can't I loop the P51? PPS the B52 rolls very nicely. Of course the real wings might fall off. Not sure I'd like to go to war in an aircraft whose wings fall off. Curiously confused Vivian Meazza _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
