KLRDMD

Last year I paid $4,675.00 for the RAC-200-1-12D unit delivered. Then I paid $555.41 for labor and materials to have it "installed." It was $5,230.41 all-in.

Just a couple of additions/corrections. The A/C unit weighs 42 lb. Not insignificant but also not a tremendous hit. It is truly portable and takes less than 5 minutes to put in or take out of the baggage compartment. Since the weight is in the baggage compartment it moves the CG rearward. An airplane with a rearward CG is actually faster than one with a CG more forward. I've demonstrated this many times with my own airplane with the A/C in and out. And, the entire reason I went to a Bonanza from a Mooney was the Mooney had insufficient useful load for my needs. I picked up well over 200 lb useful load in the Bonanza.

I had the 28V version in my Baron but the Bonanza is 14V. The 28V works better but I'm happy with the one have now. It isn't modern auto A/C quality/cooling but it sure is better than nothing.

I have the 14V system and it does take a little planning but works fine. I have a 70A alternator so I turn the A/C off when I raise or lower the landing gear or flaps. That works fine. I probably don't have to but I feel better not stressing the electrical system.

Make it perfect. I have one in my Bonanza and it works well. http://www.arcticaircooler.com/product-p/rac-200-1-12d.htm

Maintenance on my P337 was reasonable.

I've helped a few people on this board and others find airplanes that were right for them. Over my flying career I've owned more airplanes than the average pilot, I would guess. Feel free to PM airplanes you're looking at and I will tell you what I see and what I suggest. I am a CFI (and CFII, MEI & ATP) and have owned four Mooneys and flown dozens. I do a fair amount of Mooney transition training too. Full disclosure: the last guy I helped ended up buying a Bonanza. I will truly suggest what I feel is the right airplane for you once we define your mission and that was the right one for him and his family. And I just do this for fun.

I never made such an ascertain. I simply provided data that an average pilot can use while flying his airplane, not theoretical issues that we can't control.

I'm not. I'm asking what should an average guy flying his airplane do as far as determining where to properly operate the engine.

For those of us flying around in the real world, what do you suggest we use that's better than what APS has provided us?

So what's the answer?

https://www.controller.com/listings/aircraft/for-sale/192266609/1994-mooney-m20j-mse

Airspeed may be different, I have no idea. But if you are LOP, fuel flow alone determines percent power.

It shouldn't make any difference when LOP. LOP, % power is determined exclusively by fuel flow, nothing else.

The correct way is easy and you don't even need a full engine monitor as some people think. You just need a good fuel flow device. Go to cruise altitude and set up the airplane for cruise, I'm assuming that's full throttle (+/- 20-23" MP) and 2500 RPM. Over a period of about one second pull the mixture back to 8.5 GPH (OK, technically 8.6 GPH). Done. You're at 65% power LOP. It really is that easy. I've attached portions of the LOP chart for a Lycoming IO-360 engine at 8.7 compression ratio and 200HP. The chart is FF/HP/%HP while LOP.