Alec246 Posted June 19, 2023 Report Share Posted June 19, 2023 (edited) Hey guys! After checking sources, and asking a real DA40NG pilot about correct behavior, I am confident the Prop RPM behavior controlled by the FADEC is in need of a fix. After Takeoff, when I reduced power to 92%, the RPM should have gone to 2100RPM, instead it stayed around 2250RPM, and to reach 2100RPM, I needed around 80~85%. That behavior is controlled supposedly by the Throttle Lever position, and not influenced by the load on the prop, etc. So, basically a fixed schedule between throttle position and Prop RPM. This Throttle Position vs RPM Scheduling was posted also, It shows perfectly how these two behave across all power range Hope it helps!! Regards Alexis Edited June 19, 2023 by Alec246 Quote Link to comment Share on other sites More sharing options...
Coop Posted June 26, 2023 Report Share Posted June 26, 2023 Hi Alexis, I've heard conflicting information both ways on this. From the docs, it is pretty clear as you mention that the x-axis of the RPM schedule is not % Load, but the physical power level %. The propeller controller is already scheduled to the chart referenced above based on this. Quote Link to comment Share on other sites More sharing options...
Alec246 Posted June 27, 2023 Author Report Share Posted June 27, 2023 (edited) Hey Coop! Indeed it makes sense your point. I decided to chase down the rabbit hole, and I found these graphs which brings us more data to solve this question. This shows that the Power Lever Position (PL) will exactly target PowerLoad% in flight, so 92% of Power Lever must mean 92% indicated Load%. It looks to me as a linear relationship across the entire power position range. Around 800mbar pressure altitude though, Load% starts to drop, around 70% PL keeps the Load% through all altitudes What is also interesting, is that I learned that the Austro AE300 Diesel needs a Low Power Correction, starting at 800mbar. So, Bringing the Power Lever to 0 above roughly 6000feet, you will not get Idle Power anymore, a Low Power Correction is incrementally added, the higher you are. Some nice 100% - 2300RPM and 92% - 2100RPM Power Load% relationship with Altitude as well in this one, also including Manifold Intake Temperature influence. Too bad they dont give straight OAT for easier match with the Sim. Edited June 27, 2023 by Alec246 Quote Link to comment Share on other sites More sharing options...
Coop Posted June 28, 2023 Report Share Posted June 28, 2023 Good catch! I'll get this logged and see how we can get this integrated. 1 Quote Link to comment Share on other sites More sharing options...
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