On Wed, 2003-08-20 at 14:47, Manuel Bessler wrote: > Hi all, > > > I'm working on a Boeing 717-200 flightmodel (jsbsim) and the 3D visual model in > blender. > > (I've uploaded it here for now: > http://cockpit.varxec.de/fgfs/B717_model_1.tar.bz2 [180k]) > > This is my first attempt at a flight model. I've learned some stuff > about aerodynamics in the process, but am still barely scratching the > surface. > > Since the 717(aka MD-95) is still pretty new, there's not much > information about it on the net. > I've used some numbers from the tables at www.bh.com > I got started with David Culp's Aero-Matic scripts but heavily modified > the fdm config file afterwards. > > My biggest problem with the flightmodel is that elevator seems _very_ > sensitive. (ie. when flying with the keyboard, pressing up/down _once_ > will let the plane pitch about 10+ degrees up/down) > I compared my values in the <FLIGHT_CONTROL> section of the > config with some others, like the F100, and they are the same although > the F100 doesn't seem to suffer from the same problems. > I've also used MoI values similar to those of the F100. > Any suggestions for the fdm/aero beginner ?
The problem is probably not in the flight controls, but in the aero. Try either reducing pitching moment due to elevator or increasing pitching moment due to alpha. I can be more specific if you e-mail me your config file. One note of caution: the keyboard increments are necessarily kind of big anyway. > > Another problem (I think) is the lack of lift. I have only found > something for the DC-9 (which is granddaddy of the 717): > Clmax=2.0 > Aero Matic guessed around 1.4 for my input. 1.4 is probably a skosh high for flaps up. For full landing flaps, it's going to be considerably higher. Do you have any stall speeds? > > Now, I don't know how to correct that into the values in the fdm config. > > > 3D Modelling: > I've messed with blender a few times over a couple of years now. > But I'm not a big artist and I am not very good with coming up with > smart ways of how to model a certain thing. I was just wondering if > there's a blender tutorial for modelling planes, esp. for flightgear. > I googled for it but didn't find anything. > The fuselage front and rear were the biggest problems for me. I ended up > using nurbs circles along the length of the plane and then converting > the nurbs circles into meshes. Then I manually created the faces (ie. > marking 4 vertices, FKEY, until done) which was tedious work :) > Is there a better way of doing this ? > > I've got the basic model finished, now I need to add(or seperate) the > moving surfaces out of the wing and tail. Maybe cutting out using > boolean ops. Is that how you do this ? > > It'd be nice if we had a tutorial (like those of the blender community) > of how to make a visual model for flightgear using blender. > > Any help is appreciated. > > > Regards, > Manuel > > _______________________________________________ > Flightgear-devel mailing list > [EMAIL PROTECTED] > http://mail.flightgear.org/mailman/listinfo/flightgear-devel -- Tony Peden <[EMAIL PROTECTED]> _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
