I believe.) :-)
- The height of the navaid was not being properly converted to meters
before being used in our internal calculations. This caused the GS
to be placed too high.
- I was using the wrong trig function to calculate the current approach
angle of the aircraft. The distance to the GS source is the euclidean
point to point distance and represents the hypotenuse (not the ground
distance) so I need to use asin() rather than atan() to calculate the
angle.
- I was calculating distance directly to the GS source, rather than
taking into consideration that the GS transmitter projects a plane,
so I need to take the distance to the line where that plane intersectso
the ground. Previously, the way I modeled my distance calculation, the
GS transmitter effectively formed a 3 degree cone from the source. The GS
transmitter is usually placed a 100 meters or so off the runway edge so
the cone model could never bring you in to the touch down point precisely.
With these changes, the GS will bring you in precisely to the touchdown
point as defined in the default.ils.gz file (it wouldn't before.) The only
issue that remains is that it will bring you in to the elevation defined
in the ILS database, which doesn't necessarily match the DEM/SRTM terrain
at that point. Still on average, this will be a big improvement until we
can do a better job of getting the runway end elevations nailed correctly.
Some more cmall changes to the SimGear header files and removed the
SG_HAVE_NATIVE_SGI_COMPILERS dependancies from FlightGear.
I've added a seperate JSBSim patch for the JSBSim source tree.
My last patch fixed the initialization problem only for the main branch, but
ignored the _MWERKS_ branch.
- merged the branches, only the loop head needs different treatment;
- don't access n.type before it is initialized (valgrind complaint)
- created a constructor; the operator>> wouldn't have initialized all
variables in case of a broken default.nav.gz entry, so we would have
got a mixture of the broken one and the previous one; in case of
the first entry, that would have made nice random values ... ;-)
- move the automatic FGNav variable into the loop, so that the gets
cleanly constructed for every database entry.
- commented out the frequency min/max exploration, which isn't used at all
- updated the commented out debug output statements, which were simply
copied over from the nav* files, but never adapted (I needed them :-)
