I said the other day and I will say it now the FDM does NOT require a 3D model.
Have a look at the attachment this is the 747 flying sideways,quite happily,
as a 737.If the 3D model affected the FDM then this should not fly.
The 3D model should have its MRP as close to the CofG as you can get, if
not you have to supply FG with offsets so the model appears to fly
properly.
Take Lee's P51 it has its MRP at the nose.Now for a little exercise take the
AC3D file and put it in the 737 models file and name it what ever the 737 AC3D
file is called and then run FG the A/C will appear to piviot around the nose.Looks
a bit like the tail on a dog waging.A word of warning if you do this save your 737
AC3D file first and remove any animations in the model XML file as they will crash
the sim.
Now I can put Lee's P51 into AC3D and in about 3 sec's move the model so that
the origin of the graphics program and the centre of the model are the same.Then when
I load the P51 back into FG I would not have to provide any offsets to make the
model appear to fly correctly.
So it would seem logical to make the MRP as close as possible to the CofG so no offsets
have to be supplied and FG does not have to spend time calculating were the model is.
It is my understanding that the offset system was devised primarily to allow MSFS A/C
to be positioned correctly.I stand corrected if this is not the case.
As for moving the CofG as the A/C flies or as it is loaded.If it is not already implimented
then it would be a good thing.The CofG is the most important factor because if it is
out of limits you dont fly.In Boeing A/C the stabilizer has to be in the green band for
T/O if it is not the load has to be shifted till the CofG is in the green band for the stabilizer.
The CofL and the reference point I would think are only manufacturing and maintenance
figures.The only time I had anything to do with CofL was when I was doing my A/C theory
Also if you have a look at most (if not all)MSFS models you will find there MRP in the middle
of the model.
Having throwen some hand grenades I will retire to my bunker and wait for the incoming LOL.
Cheers Innis The Mad Aussi
_________________________________________________________________
Hot chart ringtones and polyphonics. Go to http://ninemsn.com.au/mobilemania/default.asp
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