CCAS

Thanks Mike - will do. I'm heading back to the airport tomorrow morning and will take a look with the cowls off.

Thanks very much! I'll give Pat a call in a couple minutes. I spoke to David yesterday and he's slammed with other work so not able to make a site visit to 5C1 unfortunately.

Looking for recommendations for a Mooney A&P at Boerne Stage airport NW of San Antonio. My '89 201 is AOG for popping ALT FIELD circuit breaker under multiple conditions. I've seen the various threads on MS that seem to be similar but nothing exactly matches. Hoping to find a mechanic with some experience troubleshooting alternators, voltage regulators, etc. I'll owe a beer to anyone who can connect me. Thanks!

This is a longshot but I wonder if the Kerrville factory might be able (and willing) to perform a retrofit of one of the original oxygen drawings for the airplane. Drawings 870007 and 870029 flight manual supplement (attached) applies to J/K/L/S models. Not sure which model you have. And, not sure how much labor and parts might be. Would likely exceed the Precise Flight O2 mod unless it was a straightforward install. Flight Manual Supplement_OXYGEN_SYST--J-K-L-S.pdf

Have you tried contacting the folks at Air Mods Flight Training Center at N87? https://www.airmodsflightcenter.com They checked me out in my 201 about four years ago and the local expertise with the Mooney Service Center was helpful.

Until recently I had my 1989 NA M20J based in Colorado Springs and flew back and forth over the Rockies often at 16K/17K (IFR) and 16.5K/17.5K (VFR). Other than climb rates slowly decaying once above 10K' or so, reaching those altitudes isn't too challenging as long as you're patient. Once at crusing altitude, my engine doesn't like LOP operations so I run ROP Economy Cruise (25 deg F ROP) and that's my baseline for power and performance estimates. I'm certainly not an expert (I'm not an A&P, nor a test pilot, and I've only got about 350 hours of IO-360 Mooney time) but after taking a look at some of your indications I had a few observations and comments. Apologies in advance if any of the following comes across as obvious, unnecessary or unhelpful. - Outside air temperature: -18 degrees C is close to standard day at that altitude (I believe rough estimate for standard temp would be -20 deg C) so nothing to indicate that non-standard temperatures were robbing you of performance. - Airspeed: As you pointed out, it seems low to True out at 148 MPH (approx 130 KTAS) at that altitude in your J. I could generally count on economy cruise at 138-142 KTAS at similar altitudes with similar gross weight. At those altitudes any mountain wave turbulence, rotor currents or other up/down drafts will spoil a consistent TAS (sometimes for the better but often for the worse). In any case, airpeed is directly related to the power being delivered by the engine. - Power: You're at 47% power with 15" MP and 2420 RPM. My POH Speed/Power/Altitude chart (max GW) doesn't display direct data above 14K' so I have to extrapolate a bit to estimate what TAS I'd expect for a 47% power condition at higher altitudes....when I do, I come up with a TAS of about 128 KTAS at 16K' and about 129 KTAS at 18K'. I'd say your airplane is giving you the speed it should for the power it's producing. FYI, I typically plan for 55% power (economy cruise) at 16.5K' using approx 17" MP/2700 RPM. But at 17.5K' I may only be capable of 50% max power (approx 16" MP/2700 RPM). - Fuel Flow: You're indicator shows 9.0 gph at 47% power. That seems rich from what I'm used to. For 50% economy cruise at 17.5K I'd normally see about 8.0 gph; and the few trips where I pulled the prop back to 2400 or 2500 RPM I'd see somewhere around 7.5 gph at approx 45% power (economy cruise). - Oil Temp: You're showing 192 deg which I'd say is quite good. I strive to keep mine below 200 deg but on some days, especially in higher-than-standard OAT conditions at that altitude, I've seen oil temp increase to 210-220 deg when I'm at 2600/2700 RPM. - EGT/CHT spread: Without seeing each of your cylinder CHT/EGT values it's tough to know if that spread you have displayed is normal or not. I've got a JPI 730 engine monitor and my values have very little spread across each cylinder. Your one displayed digital CHT (379 deg) seem reasonable but at your power setting I would have expected it to be a bit cooler (maybe 325-350 or so). Your EGT of 1191 deg seems cooler than I would have expected. - Throttle setting: I don't think you mentioned where you had your throttle. When I'm on a cross country flight, my throttle stays wide open from take off, through climb, and constantly during cruise....especially at higher altitudes. The first time I ease it back is when I'm managing airspeed and CHT temperatures during descent. - Mixture: You said you were having difficulties leaning at that altitude but I don't have any insight here. My technique during a high altitude climb is to coursely lean passing 10K' to approx 10 gpm ff, then again passing 14K' I lean to 9.5 gpm and then after a couple minutes settled in at final cruise altitude I'll use my JPI to fine tune my mixture to achieve 25 deg ROP. - Cowl flaps: I'm assuming your cowl flaps are closed and aligned flush with the cowling. Based on your engine display and aircraft performance data in the photo, I'd agree with you that you're not making max power at that altitude. Two possible causes could be either an engine issue (as others in this thread hinted at) or pilot power managment technique (throttle, prop and mixture settings). First thing I'd confirm is proper pilot power managment at that altitude (my technique is wide-open throttle, prop at either 2600 RPM or 2700 RPM and mixture leaned to 25 deg ROP). If I were sure I had those three controls set accordingly and I still wasn't getting the power I expected, I'd schedule some time with an A&P to investigate engine performance.