On Thursday 12 February 2009 02:51:09 pm Melchior FRANZ wrote: > * gerard robin -- Thursday 12 February 2009: > > Some Aircraft modelers prefer to define the Aircraft FDM > > customized more easy to fly, which can explain that P-51 > > behaviour. > > You are the main source of unjustified, malicious claims. > > No FDM developer in FlightGear ever made the config easy > to fly rather than realistic. If you know anything else, > then please "put up or shut up". If some FDM is less realistic > than it should be or could be, then it's not intentional, > but because of lack of time, data or knowledge. > > m.
There are two significant issues with the current FDM of the P-51D. The first, as mentioned by Melchior FRANZ, is stall characteristics that are much too gentle. This airplane has what is called a critical wing meaning that it stalls very abruptly and violently and it should be almost impossible to have it mush straight ahead for more than a fraction of a second when stalled. In fact it should drop a wing and roll inverted with only the slightest provocation when it is even close to being stalled. The current FDM stalls like a very fast trainer and this airplane should not fly like a trainer. The second significant issue is that the engine of the simulated P-51D will run inverted. This power plant has a carburetor and it should lose power fairly quickly when ever the airframe experiences negative G. I suspect that other aircraft using this same power plant (and perhaps other power plants that use carburetors) probably have this same issue. There could be other issues with the FDM as well. For example I think that perhaps there should be more drag when the flaps are fully extended but I don't know this for sure. But I do not think that these issues are deliberate on the part of the modeler. Rather I think these are because the modeler did not have the necessary data to make things work correctly. Hal ------------------------------------------------------------------------------ Open Source Business Conference (OSBC), March 24-25, 2009, San Francisco, CA -OSBC tackles the biggest issue in open source: Open Sourcing the Enterprise -Strategies to boost innovation and cut costs with open source participation -Receive a $600 discount off the registration fee with the source code: SFAD http://p.sf.net/sfu/XcvMzF8H _______________________________________________ Flightgear-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/flightgear-users
