[moving to the list] Curtis L. Olson writes:
> This makes it difficult to just define the power source for the > navcom in the instrument panel config file. We need to kill the > audio when the power goes out and not have the autopilot continue > to track something that is alledgedly off. Right -- the autopilot has to take its input from the nav radio, not from the actual /position and /orientation properties. That's important not only to deal with power-out situations, but to model VORs realistically. The autopilot doesn't have to know where the nav radio is drawing its power from, though, as long as it knows when the nav radio is supplying information. Yesterday on my return flight from Peterborough to Ottawa I practiced radio navigation by tracking to the YCF VOR then following V104 at 5,500ft to the LANRK intersection (where it bends northwards) and on towards the YOW VOR until Ottawa Terminal vectored me in towards the airport. Since I was flying VFR (necessarily), I was able to compare my position with the airway on the map, and I found that when the nav1 needle was centred I was often a few miles off course (my backup GPS also agreed that I was a few degrees off the airway). A an analog VOR gauge is allowed to be off by a few degrees, and then other external factors may affect the signal as well (sometimes the needle would swing off for a few minutes then centre itself again). This might be a surprise to non-pilots (it surprised me because I hadn't thought of it before), but following a victor airway is *much* less accurate than following a route by pilotage given VMC, a map, and sufficient landmarks. > I could hardcode the bus property names provided by the c172 > electrical system, but this hoses us for other aircraft. They should be parameterized in the XML instrument config file so that the aircraft file can plug the right instrument into the right bus. Note how some instruments are already parameterized to use different engines or receivers. > Another solution that I am favoring at the moment is to allow an > arbitrary list of property names for a node. This way avionics-bus-1 > could advertise to: > > /systems/electrical/outputs/avionics-fan-power > /systems/electrical/outputs/gps-mfd-power > /systems/electrical/outputs/hsi-power > /systems/electrical/outputs/navcom-power[0] > /systems/electrical/outputs/audio-panel-power[0] I prefer that the GPS connect itself to avionics-bus-1, or more specifically, that the aircraft config file connect the GPS to avionics-bus-1. That's nice for designers, because it will feel a little like actually building an aircraft. All the best, David -- David Megginson, [EMAIL PROTECTED], http://www.megginson.com/ _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
