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CoolP

RPM limit

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A question regarding the lower rpm setting. Concerning the economic cruise settings from the manual, I was up to reduce the cruise rpm to 2100 as by this chart.ecorpmq.th.jpg So cruising around 6000ft gives me a Manifold Pressure of 21.0.Once set up, I reduce the rpm but can only reach 2200 as that's the lowest possible setting in the sim (from both gauges, analogue and digital).mpandrpm.th.jpg83416030.th.jpgI can see the VC rpm lever moving further downwards, but the rpm don't reduce some more.I've tried it with the FSX keyboard commands and the prop lever on my throttle. If I raise the Manifold Pressure, this lower limit moves up to around 2300 at full throttle (at that altitude).Don't worry, I'm not trying to fly some 1200 with high MP or so, but shouldn't the rpm reduce to much lower settings than those mentioned 2200, for example 2000? The A36 is the only plane that behaves like this from my experience, so I was wondering about the nature of that feature.Any information is appreciated. smile.png

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I've noticed this as well. When climbing to altitude the I seem to be able to set the RPM to whatever value I'd like within the normal operating range, once I level off however and the aircraft establishes it's cruise speed the RPM seems to stay fixed at whatever value I set in climb regardless of prop lever position. The other strange RPM setting I've noticed in this aircraft is that it will not idle on the ground below 1000-1100 RPM. I understand this could be a calibration issue, so to double check I've used the F1 command to set the throttle position to idle with 0% showing on the tooltip. Most all manufacturers for the aircraft I fly in real life call for a ground idle of no lower than 1000 RPM, so I could understand the thought process behind that number, however almost every aircraft I've flown has to have the throttle increased slightly from its physical idle stop in order to obtain that 1000 RPM.

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Guest bstolle

That's weird as I encountered this 2100 RPM problem during development but it know that I have corrected this bug. I'll look into that ASAP.Are you flying at the target speed when this problem occurs or faster than that?E.g. if you are cruising at 150kias and you want to slow down to a lower power setting cruise the RPM will not decrease to 2100 if you are faster than the 125kts target speed in your 21/21 example.

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Good point, I have to check my speeds again, but I think I saw 132 or so, so that would explain the deviation. Edited.I've tested her with cruising some minutes on that 21/21 setting (standard ISA day, 6500ft, 2C OAT, all weather cleared in FSX, leaned to approx 20 degree lean) and here are the observations.The IAS is 139.MP is 21.0.RPM are 2100 analogue and 2123 digital. So I could reach the charted values which is good.FF is 10.4 gal/hr.The prop lever has no effect after around 70%, so anything from 0% up to 70% does not trigger a change on the rpm. One can see the VC lever moving though. That's the main point I'm wondering about.

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Guest bstolle

Once the prop reaches its highest pitch (minimum RPM), any decrease in resistance (like a higher airspeed) increases the RPM (at the same powersetting). If you fly slower and/or at a reduced power setting you can decrease the RPM much more with the prop lever.

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Guest bstolle

If you fly slower at a lower power setting there's not that much leeway as you can decrease the prop RPM even more.Try flying at 70kts and check until which RPM the prop lever affects RPM.Might be for small part an FSX 'problem' as well it's exactly the other way round with the mixture lever.Lot's of 'leeway' at the top range.

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Guest bstolle
The other strange RPM setting I've noticed in this aircraft is that it will not idle on the ground below 1000-1100 RPM.
Reduced the idle RPM to 750 for the upcoming patch.....

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Thanks for the update, happy with the rpm range now, so I can explore the also new FDE now. smile.png

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