David Megginson said: > Andy Ross wrote: > > > Tune up the starter torque to match the recent changes to engine > > friction. We should get these better calibrated at some point... > > When you engage a starter on a piston engine (I have no turbine experience), > it spins the propeller at an extremely slow, constant speed -- maybe 30 rpm > -- until the engine fires; at that point, the engine spins the propeller up > to speed (say, 1000 rpm with the throttle slightly open) almost instantly. > > With YASim (and possibly JSBSim -- I don't remember), the starter seems to > gradually spin the propeller up to the engine's idle speed (600-800 rpm), at > which point the engine takes over. That has no relation to what really happens. >
As far as YASim is concerned I don't think it would take much to fix this. Right now the start spins up to the idle rpm value (iirc) and then switches the engine to run mode. You could probably do something like not let the rpm increase beyond 30 (or whatever) unless the magnetos are on and fuel mixture is available. If the starter function is torque based (probably it is) you could just make starter torque a low value until you reach firing rpm and the right values for running are there. The first couple of pops are what get the engine up to idling speed by adding to the starter torque. A third approach might be just decrease the starter torque and have the yasim engine switch to run mode at some other value below idle, but I'm not sure all that would be involved (maybe just a separate config value). Best, Jim _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
