On 12/20/2008 08:52 PM, Ron Jensen wrote: > Yes, 2400 is full fine. I asked about full coarse. I was under the > impression, perhaps mistaken, that you expected the engine to turn > faster than 1750 rpm with the lever back (coarse):
OK, sorry, most recently I misread course/fine. My bad. However, previously I did answer (as best I could) the question about full coarse. On 12/20/2008 03:11 PM, I wrote: >> I reckon full back might set the governor for somewhere >> near 900 but I'm not sure. I recall it is impressively low, but >> I don't recall the exact number. I will add that it is for sure below 1750 RPM. Far, far below. The preflight runup in the Real World Cessna 182 is performed at 1700 RPM, and "exercising" the prop requires bringing the governor below 1700, and that requires far less than full-back on the control. > "Consider the following scenario: The Sim World c182rg is sitting on > the runway at KSFO. The propeller control is pulled back, so that the > engine is operating at relatively low revs, about 1750 RPM in > contrast to redline which is 2400 RPM. The pilot can observe that if > the throttle is open anywhere between 52% and 100% open, moving the > throttle has no effect on the MAP." I will also add that the precise value of the revs in this scenario (1750 RPM) is of no importance to the point I wanted to make. My point remains that in the Sim World c182, you can under some conditions bring the throttle back nearly half way with *zero* effect on the MAP. The MAP remains equal to the ambient static pressure. The idea of significant flow with *zero* pressure drop across a half-closed valve is in flagrant violation of the laws of physics. I emphasize that for today at least, I am not talking about the code and not talking about the configuration data. I am talking about the behavior : the directly observable in-the-cockpit behavior of the Sim World model. The MAP-vs-throttle behavior and the power-vs-throttle behavior are flagrantly unrealistic. Yeah, the minimum revs on the SW governor is also unrealistic. That wasn't the point I wanted to emphasize, but you can add it to the list of bugs if you want. ------------------------------------------------------------------------------ _______________________________________________ Flightgear-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/flightgear-devel
