I purchased the Mooney mod and have found it perhaps my best mod for general aviation flying, but I am clueless as to how to set prop and mixture settings (other that full rich, max prop on takeoff and climb). Can anyone point me to a tutorial?
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Are you referring to the Carenado Mooney Ovation M20R? If so, and if you installed it in the default location, you should find all documentation, including checklists, here:
C:\Users"YOUR USER"\AppData\Local\Packages\Microsoft.FlightSimulator_8wekyb3d8bbwe\LocalCache\Packages\Official\OneStore\carenado-aircraft-m20r-ovation\SimObjects\Airplanes\Carenado_M20R_Ovation\Documentation
Also there is more information and links in this thread:
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Disclaimer I am not a Pilot. And I basically just learned this over the last few days. Just bought the Mooney as well. Now that, that is out of the way.
This is how I do it, I’ll basically give you an example. Also note that there is a Chart about this on the back of the Pilots Sun visor. If you flip it down.
So upon climb out (climbing to Altitude) you can adjust Manifold Pressure (MP) to 25" and keep prop feather at 2500RPM. 25 and 25 I hear that term thrown around a fair bit, I think its standard practice. Or I could be wrong, ha ha.
So lets say you are cruising at 8000ft. Just sight seeing. This is just an example not written in stone. You could reduce your MP to say 18-20". Feather your prop to 2300RPM. Then you would watch your EGT (Exhaust Gas Temperature) gauge. The temperature will fluctuate with how much Fuel you feed it.
So there is a few terms here “Lean of Peak” and “Rich of Peak” The sun visor in the plane says to tune 50F either Lean or Rich of peak. I usually tune 50F Lean of Peak to conserve fuel. Peak refers to “Peak Temperature” Showing on the gauge. You will also see your fuel flow (GPH) change when you do this
The EGT gauge is showing 1315F in this picture. I was just sitting on the tarmac when I took the picture so don’t take too much stock in the other gauge read outs.
Start with your fuel Mixture at 100% start backing that lever down watching the EGT Temperature gauge. At some point the Temperature on that gauge will start going up. Then it will stop, which will be Peak take note of that temperature. Then the temp will continue to fall as you keep backing it off. As you lean out the fuel mixture.
So if 1315F was the Peak temperature. 50F “Lean of Peak” would be 1265F.
(50F Lean of Peak is for best Cruise Economy)
(50F Rich of Peak is for best Power)
In real life if you go too lean, you can damage your engine. If you are too rich I guess you are basically flooding your engine and needlessly burning fuel. On a side note if your EGT is dangerously hot for some reason I believe you can feed the engine a little extra fuel to cool down the temperature as well.
Also when you make altitude changes you should retune your fuel mixture. I’m not sure if it is a1000ft. flight level change kind of thing or not. I usually re adjust it, if I am staying at the new altitude for a while. Once you figure it out, it only takes about 30 seconds to adjust.
You see a lot of posts about people not being able to gain altitude. I believe it is because their fuel setting is too rich on the plane so they aren’t creating enough Horse Power or Peak Horse Power.
Hopefully this is the info you were looking for (and I am actually doing it right), or at least enough to get your own research started.
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Basically flip down the sunvisor and look at the chart.
Start with a rough power/throttle setting you want to use (100% / 75% / 65% etc etc) depending on how fast you want to go and then choose your rpm and from that section of the chart and come down to the appropriate altitude and read the recommended manifold pressure from that. You will need to adjust the number you read off the chart for Outside Air Temperature, the instructions for that are at the bottom of the chart. Note you can optimise either power or economy within each power range by how you set mixture.
As far as mixture and EGT goes the actual numbers on the EGT gauge are not that relevant it is the point it peaks at that counts, for cruise you will generally just adjust mixture till it peaks and back off to slightly rich of peak (say 50 degrees before peak) if you have chosen a “power” setting in order to keep the engine cooler - or if you are going for “economy” settings from the sun visor chart to optimise fuel efficiency leave it at peak or go very slightly lean (no more than 50 degrees past peak) . You can actually tweak these mixture settings further by adjusting mixture to give the exact fuel flow from the chart for power or Economy.
Example from the chart below.
- Let us supposed you are at 4000’ with OAT of -3C so 10 degrees below standard by the chart and are happy enough to use 75% throttle. Looking at the chart below you can choose 2300, 2400 or 2500 rpm at 75% power. The lower the RPM the better the better the economy but the slower you will travel. Let us choose 2400 RPM for this example. Coming down t the altitude section we see that 75% power at 4000’ gives a manifold pressure of 23.2 but we are at 10 degrees below standard outside air temp so we set our manifold to 22.8 inches.
In terms of Engine Temperatures, the one you should be watching is actually the Cylinder Head Temperature ( CHT gauge) . I generally try and keep this below 400 especially in a sustained climb. Allowing temperatures to sit over 400 for any sustained time in a real engine would probably shorten the engine life quite a bit.
Cylinder Head Temperatures is one of the reasons you should not cruise below 2300 RPM (or 2400 with 100% power) in a M20 Mooney. Lower RPM at a particular power setting means higher CHT.
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Thanks to all for the super advice. Will apply same and see how it goes.
If you like, you could check out my M20R Checklist/Guide. There you also find notes on how to lean that plane and what power settings to use at climb and descent. I also included a very rough fuel planing.
Kind Regards
JayDee
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Such great advice! 
I will add a tidbit or two:
The Mooney does not allow direct control of cowl flaps. Airspeed and RPM are, therefore, more critical to maintaining proper Cylinder Head Temperature.
As @EdamllamaB mentioned, CHT is excess of 400 degrees for any length of time is not a good idea. To help with that, Mooney has marked a “Blue Arc” on the EGT gauge. While climbing it is important to keep the temp within the Blue Arc. Only when established in a level cruise should you allow EGT to go beyond the Blue Arc range.
I have found that - between 7,500’ and 8,500’ on a “standard” temperature (OAT) day - an EGT reading of approximately 1540 degrees F is about 50 degrees rich of peak. If memory serves, that’s the suggested leaning for best power in the M20R. I nearly always set cruise RPM between 2300 and 2400. At that altitude throttle is typically at WOT.
Finally, and especially at or near sea level, when applying power for takeoff I never use WOT. I bring the manifold pressure up to 25" and watch the Blue Arc on the EGT gauge to make certain I do not exceed that limit. Initial climbout in the Mooney is pretty amazing anyway, so it is not necessary (or advisable) to simply “firewall” the throttle. At high altitudes that may be necesary, and above 5,000’ it pays to do a runup prior to takeoff at 2000 rpm while sitting in the apron. Adjust for peak EGT and then ease back slightly to get 50 degrees rich; that way you know you’ll be making full power upon takeoff.
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“WOT” is that Wide Open Throttle? Some of the meanings I found searching on the web, I was like nope pretty sure that isn’t what this person is talking about lol.
lol!
Yes… WOT = Wide Open Throttle…
Thanks. The guide looks like it will be very helpful.
Hi,
il might be just me but since last update (19 oct.) it seems like the “set best mixture” key cuts off the fuel (red lever) and blocks controls so i cannot move it back ( it moves if i use the mouse but comes back in the cutoff position right away).
Tried it in the King Air…no problems.
Any ideas what i am doing wrong?
How do you keep your CHT below 400? My CHT is always staying around 420 no matter what setting i adjust?