Alex Romosan wrote: > Andy Ross <[EMAIL PROTECTED]> writes: > > Remaining outstanding YASim bugs are (people should shout if I've > > forgotten something): > > i don't know if this a bug or if that's how the modeling is supposed > to work but the a4 is almost unflyable. when i use the controls the > plane gets into these weird damped oscillations. i never flew an a4 > but i find it hard to believe that the real jet would exhibit this > kind of behaviour. the harrier is much better.
Indeed, the A-4 model is much less statically stable than the Harrier. But I wouldn't call it unflyable. It's certainly harder to fly than a lightplane or jumbo jet, but then, it's a 1960's attack jet -- it's not *supposed* to be easy to fly. :) Try being lighter on the controls, and try a set of rudder pedals if you haven't already. I honestly haven't had any serious difficulties maneuvering the plane. This is one of those classic problems -- traditional consumer flight simulators (and this is especially true of military sims) have done a great job at modelling cockpit avionics and UI issues, but a really piss-poor job at the aero modelling. Pretty much every sim I've tried is absolutely rock-steady. Stomp on the rudder and the nose goes ever so slowly to the side, then back to the center. I'd say that the fact that YASim enters a violent yaw oscillation when you stomp on the pedals is a feature, not a bug. Since all the force equations and solution routines are exactly the same as the ones for the lightplanes (which generally behave pretty realistically, stability-wise, under YASim), I'm inclined to think that the A-4 in fact *is* this unstable. Any ex-Navy pilots on the list? :) That being said, if you really feel that the stability is too low, try modifying the "effectiveness" values for the hstab and vstab entries. This is a dial that multiplies the total force generated by the surface; more force from the tail surfaces means more stability. You could also try moving the c.g. forward using ballast, which will have the same effect. Andy -- Andrew J. Ross NextBus Information Systems Senior Software Engineer Emeryville, CA [EMAIL PROTECTED] http://www.nextbus.com "Men go crazy in conflagrations. They only get better one by one." - Sting (misquoted) _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel