On 01/01/2009 06:14 PM, dave perry wrote: > John, I agree completely with pursuing such a standard. Having a > documented standard would make both AC and instrument modeling easier.
:-) > Either approach could work and I could live with either. With the > "jumper" approach, we should also have a fraction required such as 0.8 > or 0.5 used in the power test as you suggested. In the pa24, with out > the engine running and current being drawn, the battery actually > discharges and w/o such a fraction required, the instrument would > immediately fail with just the battery power which would be very > unrealistic. OK, it sounds like things are moving in a very good direction. Pursuing that line of thought ... what about this: The "jumper" could go into the property tree, perhaps as follows: For designers who prefer real volts: /systems/electrical/nominal = 12 /systems/electrical/subnominal = 7 For designers who prefer everything normalized to unity: /systems/electrical/nominal = 1.0 /systems/electrical/subnominal = 0.6 As long as each aircraft's electrical buses are scaled relative to nominal, and as long as instruments make decisions based on comparisons to nominal (or, more likely, subnominal), then instruments should be portable from aircraft to aircraft. This gives 100% flexibility to AC designers and gives portability to instrument designers. Note: Having a separate property for subnominal is just a micro-optimization ot make xml comparisons easier. But maybe it also serves to clarify the concept. ====== The only remaining question is what to do if the AC designer has not yet implemented the nominal and subnominal properties ... or indeed has not implemented any electrical system at all. My suggestion: Nominal and subnominal default to zero. Then, in an aircraft with no electrical system at all, instruments that want to work will work if they accept voltage greater than *or equal* to subnominal. Meanwhile, instruments that want to remain off under such conditions should operate only when the voltage is strictly greater than subnominal. ------------------------------------------------------------------------------ _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
