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Cruising at 17,500 in a M20J


haymak3r

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So this weekend, the weather told me that if I didn't get out and fly, I was an idiot. Sooo, I changed the oil and went flying. I've wanted to try this for sometime now, and since I was alone, I thought why not.

I took off, and started climbing up to see just how high up the plane would get me. I did fill all the way up, so was not super light. I climbed between 800-1100 fpm up to about 12,500, and then to keep temps down, and my speed around 110 mph I reduced my climb to about 500 fpm. at about 15,500 I was climbing around 2-300fpm. at around 17, it was getting very hard to keep the engine happy, so I stopped at 17,500 to see what I could get my cruise speed up to. I trued out around 148 mph :(. I was hoping to see a little more up there, but oh well. 

One thing that surprised me though, and why I am posting this. I thought I would end up getting to a point where my AoA started getting to high, and I would lose too much speed to keep altitude, but rather, my engine was my limiting factor. In that I could no longer properly set the mixture. If I leaned any further from where I was, I could VERY noticeably feel the plane slowing down, and the engine would struggle to maintain RPM. If I richened any more, and I mean within two twists of the knob, the engine would again start stuttering/bogging? down. Hard to explain. Felt like it was loading up. My EGT's also were not consistent at all, with number 4 getting very cold down in to the 900's. I know being NA is going to be a factor, but I thought I could still control the mixture enough to keep the engine somewhat happy? 

Also, once I sped up to max speed, I am sure I could have climbed further and get in to Class A, but I called it off early. 

 

Was I doing something wrong? Just normal limitation of literally being at half atmosphere? Due to old age? lol. Plane, not me of course hehe.

Only pic I took inside:

 

Photo 24-02-10 16-34-38 3326.jpg

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I should also have added that I did not stay at 2400 rpm up there. I was trying different configurations to see what worked the best. And that makes some sense. 

And you're running an NA J?  how long does it take for you to get up to those speeds? because I was up there for 10-15 minutes messing with settings, before starting my descent.

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+1 that maybe cleaning the injectors might get you a little better performance next time.

I had my J there once after exploiting a mountain wave to get over the Rockies at Angel Fire.   Could have easily climbed up into the Class A, but I was VFR and didn't need to go any higher.   In my case the engine was fine, but I wasn't fiddling around with the mixture much other than keeping it in a reasonably happy zone.   

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1 hour ago, haymak3r said:

So this weekend, the weather told me that if I didn't get out and fly, I was an idiot. Sooo, I changed the oil and went flying. I've wanted to try this for sometime now, and since I was alone, I thought why not.

I took off, and started climbing up to see just how high up the plane would get me. I did fill all the way up, so was not super light. I climbed between 800-1100 fpm up to about 12,500, and then to keep temps down, and my speed around 110 mph I reduced my climb to about 500 fpm. at about 15,500 I was climbing around 2-300fpm. at around 17, it was getting very hard to keep the engine happy, so I stopped at 17,500 to see what I could get my cruise speed up to. I trued out around 148 mph :(. I was hoping to see a little more up there, but oh well. 

One thing that surprised me though, and why I am posting this. I thought I would end up getting to a point where my AoA started getting to high, and I would lose too much speed to keep altitude, but rather, my engine was my limiting factor. In that I could no longer properly set the mixture. If I leaned any further from where I was, I could VERY noticeably feel the plane slowing down, and the engine would struggle to maintain RPM. If I richened any more, and I mean within two twists of the knob, the engine would again start stuttering/bogging? down. Hard to explain. Felt like it was loading up. My EGT's also were not consistent at all, with number 4 getting very cold down in to the 900's. I know being NA is going to be a factor, but I thought I could still control the mixture enough to keep the engine somewhat happy? 

Also, once I sped up to max speed, I am sure I could have climbed further and get in to Class A, but I called it off early. 

 

Was I doing something wrong? Just normal limitation of literally being at half atmosphere? Due to old age? lol. Plane, not me of course hehe.

Only pic I took inside:

 

Photo 24-02-10 16-34-38 3326.jpg

This makes me think that I have something wrong with my J. I can do only 500fpm above 5k feet. 

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1 hour ago, haymak3r said:

Was I doing something wrong? Just normal limitation of literally being at half atmosphere? Due to old age? lol. Plane, not me of course hehe.

Only pic I took inside:

 

 

Could you see the curvature of the Earth from up there?? :lol:

Seriously, how long did it take to get to 17.5?  30 mins?

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Could also be magneto related. Generating good spark gets to be a little more of an issue in the high atmosphere levels. The turbos went to a pressurized mag decades ago to prevent one of the symptoms, called cross-cap tracking. Air acts as an insulator and prevents the spark from tracking across the magneto cap to the wrong electrode, firing a cylinder at the wrong time. You can't do much about that, but when the mixture starts to get hard to ignite the condition of the mags and the type of spark plug are usually the issue. Those of us who fly LOP quite a bit generally go to fine wire plugs, which perform better, and the spark in my aircraft is always better right after annual when the magnetoes get maintenance work done. 

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1 hour ago, haymak3r said:

I should also have added that I did not stay at 2400 rpm up there. I was trying different configurations to see what worked the best. And that makes some sense. 

And you're running an NA J?  how long does it take for you to get up to those speeds? because I was up there for 10-15 minutes messing with settings, before starting my descent.

No, I have a turbo J.

I took my NA M20F that high a few times. You are doing really good getting 148 up there. 

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2 minutes ago, N201MKTurbo said:

No, I have a turbo J.

I took my NA M20F that high a few times. You are doing really good getting 148 up there. 

Not Fair! :)


 

 

21 minutes ago, jlunseth said:

Could also be magneto related. Generating good spark gets to be a little more of an issue in the high atmosphere levels. The turbos went to a pressurized mag decades ago to prevent one of the symptoms, called cross-cap tracking. Air acts as an insulator and prevents the spark from tracking across the magneto cap to the wrong electrode, firing a cylinder at the wrong time. You can't do much about that, but when the mixture starts to get hard to ignite the condition of the mags and the type of spark plug are usually the issue. Those of us who fly LOP quite a bit generally go to fine wire plugs, which perform better, and the spark in my aircraft is always better right after annual when the magnetoes get maintenance work done. 

Interesting! My mag was overhauled back in April during my annual as it was up for inspection. Didn't consider that spark could come in to play here. I do run LOP as much as possible, so may consider fine wire plugs if they work better. Will look into this further. Thanks!


 

 

25 minutes ago, 0TreeLemur said:

Could you see the curvature of the Earth from up there?? :lol:

Seriously, how long did it take to get to 17.5?  30 mins?

HA! The clouds looked WAY down there, that's for sure. It is quite the difference between my normal cruise alt around 10-12. Not sure why, but it made a diff. Time wise was about 33 minutes +/- a minute. I did stop at 17 for a minute to gain more speed, and then went to 17.5.

 

34 minutes ago, redbaron1982 said:

This makes me think that I have something wrong with my J. I can do only 500fpm above 5k feet. 

I was the only person, and I had probably 59-60 gallons when I started this. I did loiter around for a bit over my town before starting this. So, around 2300 lbs. If I am at gross, I usually try to keep it around 500fpm. This keeps me around 100-105 mph.



 

 

43 minutes ago, EricJ said:

+1 that maybe cleaning the injectors might get you a little better performance next time.

I had my J there once after exploiting a mountain wave to get over the Rockies at Angel Fire.   Could have easily climbed up into the Class A, but I was VFR and didn't need to go any higher.   In my case the engine was fine, but I wasn't fiddling around with the mixture much other than keeping it in a reasonably happy zone.   


It has been a few years since this has been done. I think I will have it done during annual in a couple months. 

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3 hours ago, haymak3r said:

So this weekend, the weather told me that if I didn't get out and fly, I was an idiot. Sooo, I changed the oil and went flying. I've wanted to try this for sometime now, and since I was alone, I thought why not.

I took off, and started climbing up to see just how high up the plane would get me. I did fill all the way up, so was not super light. I climbed between 800-1100 fpm up to about 12,500, and then to keep temps down, and my speed around 110 mph I reduced my climb to about 500 fpm. at about 15,500 I was climbing around 2-300fpm. at around 17, it was getting very hard to keep the engine happy, so I stopped at 17,500 to see what I could get my cruise speed up to. I trued out around 148 mph :(. I was hoping to see a little more up there, but oh well. 

One thing that surprised me though, and why I am posting this. I thought I would end up getting to a point where my AoA started getting to high, and I would lose too much speed to keep altitude, but rather, my engine was my limiting factor. In that I could no longer properly set the mixture. If I leaned any further from where I was, I could VERY noticeably feel the plane slowing down, and the engine would struggle to maintain RPM. If I richened any more, and I mean within two twists of the knob, the engine would again start stuttering/bogging? down. Hard to explain. Felt like it was loading up. My EGT's also were not consistent at all, with number 4 getting very cold down in to the 900's. I know being NA is going to be a factor, but I thought I could still control the mixture enough to keep the engine somewhat happy? 

Also, once I sped up to max speed, I am sure I could have climbed further and get in to Class A, but I called it off early. 

 

Was I doing something wrong? Just normal limitation of literally being at half atmosphere? Due to old age? lol. Plane, not me of course hehe.

Only pic I took inside:

 

Photo 24-02-10 16-34-38 3326.jpg

I had my F at 15,500 last week and didn’t notice significant engine differences except that you’re only running on about 105-120hp, so don’t expect much.  I saw 141kts at 15,500, so yours does seem low since im in an F.  I have a Surefly mag and pretty fresh fine wire plugs though, so i think ignition was good.  In fact, it ran fine both ROP and lop.

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3 hours ago, haymak3r said:

So this weekend, the weather told me that if I didn't get out and fly, I was an idiot. Sooo, I changed the oil and went flying. I've wanted to try this for sometime now, and since I was alone, I thought why not.

I took off, and started climbing up to see just how high up the plane would get me. I did fill all the way up, so was not super light. I climbed between 800-1100 fpm up to about 12,500, and then to keep temps down, and my speed around 110 mph I reduced my climb to about 500 fpm. at about 15,500 I was climbing around 2-300fpm. at around 17, it was getting very hard to keep the engine happy, so I stopped at 17,500 to see what I could get my cruise speed up to. I trued out around 148 mph :(. I was hoping to see a little more up there, but oh well. 

One thing that surprised me though, and why I am posting this. I thought I would end up getting to a point where my AoA started getting to high, and I would lose too much speed to keep altitude, but rather, my engine was my limiting factor. In that I could no longer properly set the mixture. If I leaned any further from where I was, I could VERY noticeably feel the plane slowing down, and the engine would struggle to maintain RPM. If I richened any more, and I mean within two twists of the knob, the engine would again start stuttering/bogging? down. Hard to explain. Felt like it was loading up. My EGT's also were not consistent at all, with number 4 getting very cold down in to the 900's. I know being NA is going to be a factor, but I thought I could still control the mixture enough to keep the engine somewhat happy? 

Also, once I sped up to max speed, I am sure I could have climbed further and get in to Class A, but I called it off early. 

 

Was I doing something wrong? Just normal limitation of literally being at half atmosphere? Due to old age? lol. Plane, not me of course hehe.

Only pic I took inside:

 

Photo 24-02-10 16-34-38 3326.jpg

Freaking awesome Mooneys rock..

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On 2/12/2024 at 10:39 AM, haymak3r said:

So this weekend, the weather told me that if I didn't get out and fly, I was an idiot. Sooo, I changed the oil and went flying. I've wanted to try this for sometime now, and since I was alone, I thought why not.

I took off, and started climbing up to see just how high up the plane would get me. I did fill all the way up, so was not super light. I climbed between 800-1100 fpm up to about 12,500, and then to keep temps down, and my speed around 110 mph I reduced my climb to about 500 fpm. at about 15,500 I was climbing around 2-300fpm. at around 17, it was getting very hard to keep the engine happy, so I stopped at 17,500 to see what I could get my cruise speed up to. I trued out around 148 mph :(. I was hoping to see a little more up there, but oh well. 

One thing that surprised me though, and why I am posting this. I thought I would end up getting to a point where my AoA started getting to high, and I would lose too much speed to keep altitude, but rather, my engine was my limiting factor. In that I could no longer properly set the mixture. If I leaned any further from where I was, I could VERY noticeably feel the plane slowing down, and the engine would struggle to maintain RPM. If I richened any more, and I mean within two twists of the knob, the engine would again start stuttering/bogging? down. Hard to explain. Felt like it was loading up. My EGT's also were not consistent at all, with number 4 getting very cold down in to the 900's. I know being NA is going to be a factor, but I thought I could still control the mixture enough to keep the engine somewhat happy? 

Also, once I sped up to max speed, I am sure I could have climbed further and get in to Class A, but I called it off early. 

 

Was I doing something wrong? Just normal limitation of literally being at half atmosphere? Due to old age? lol. Plane, not me of course hehe.

Only pic I took inside:

 

Photo 24-02-10 16-34-38 3326.jpg

Looks like you are missing an EGT on Cylinder 4 and maybe Cylinder 2.

Were you using a portable oxygen tank or a oxygen generator (Inogen)?  When I first bought an M20K (231) in 1993 I thought nothing about going to 17500 with the factory O2 tank and no back up. Then after I got my instrument rating I thought nothing of going up to FL240 in the 231 and later FL250 in the Bravo - again with no backup. Now that I'm older and hopefully smarter I make sure I have a backup to my tank (Inogen which I use many times instead of the tank, and I carry a couple cans of Boost just in case). Everyone has a little different way of handling hypoxia. My IFR instructor had me take my mask off at FL240 and I kept it off for a few minutes and he had me do math problems and I wasn't having any difficulty and even a few minutes later it didn't seem like I was affected. He told me to get my mask back on and said that some people after showing no signs for awhile just black out and other people show more of a linear trend. The signs I was showing were the most dangerous since I might not see any sign of an O2 problem until it was critical.

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19 minutes ago, LANCECASPER said:

Looks like you are missing an EGT on Cylinder 4 and maybe Cylinder 2.

Were you using a portable oxygen tank or a oxygen generator (Inogen)?  When I first bought an M20K (231) in 1993 I thought nothing about going to 17500 with the factory O2 tank and no back up. Then after I got my instrument rating I thought nothing of going up to FL240 in the 231 and later FL250 in the Bravo - again with no backup. Now that I'm older and hopefully smarter I make sure I have a backup to my tank (Inogen which I use many times instead of the tank, and I carry a couple cans of Boost just in case). Everyone has a little different way of handling hypoxia. My IFR instructor had me take my mask off at FL240 and I kept it off for a few minutes and he had me do math problems and I wasn't having any difficulty and even a few minutes later it didn't seem like I was affected. He told me to get my mask back on and said that some people after showing no signs for awhile just black out and other people show more of a linear trend. The signs I was showing were the most dangerous since I might not see any sign of and O2 problem until it was critical.

I went to the cht/egt page and monitored. They are there, just not reading on the main screen. They are a few hundred degrees cooler than the other 2 cylinders. in the 900's. I messed up and forgot to bring the USB drive home so I could throw this flight in to savvy's site. :( I will certainly try to remember to bring it home next time I am at the plane.

 

I have a Mountain High o2 system in the plane, and usually use it anytime I am above 8000ft. I was definitely using it, and monitored my o2 frequently. I had it set at 18k ft, and my o2 was 91-95%. The biggest issue I find myself in is remembering to breath in through my nose. And to take full breaths in. Hopefully that makes sense.

 

I have noticed that if not being on oxygen around 11,500, that I start feeling the effects. I get a euphoric feeling. or slight dizziness? This has happened a couple times, and so basically have o2 with me all the time now. no reason to risk it.

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Many years ago I had my M20J up at FL190 heading from Utah to Wyoming to stay above the weather.  I had no problems with the engine, it ran great up there.  I would expect either a fuel injector issue or a mag issue as I had an experience with a turbo Mooney at FL200 where the mag started arcing internally but it was fine down low.  You do get slow on TAS up there but I had a screaming ground speed :-)

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Once upon a warm summer evening, I step-climbed my C up to 15,500 msl. The paper with environmental conditions scribbled on it is long gone, but I looked up some things and did some calculating the next day, and found that I had leveled off at 18,800 DA. Not bad for 180 hp, 2 souls full fuelmand a portable oxygen setup.

We didn't go higher because that would have involved changing to Center, only to descend and change back fairly soon. The controls felt mushy, and memory says that I was indicating not much above 100 mph. I no longer recall what the 430W said my groundspeed was, we just ran larger and larger racetrack patterns as I climbed, circling over that bend in the Ohio River that makes the bottom of the state.

But it did give me a good opportunity to practice emergency descents! Wheee! Point the nose down, keep IAS under redline--throttle on and throttle off. But staying below 120 mphi with Takeoff Flaps out, Gear Down and 45° bank angle really made the altimeter unwind in a hurry! A new favorite for me if needed and not in the clouds.

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RE AoA - no problem with the Mooney wing up high.  Flew at FL210 this week for a long round trip. On two occasions had ATC point out A320s 1,000 feet below me.  You could hear the surprise in the first pilot’s voice when the Mooney traffic above him was called out… I considered cautioning him for my wake turbulence but my better judgement prevailed…

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8 hours ago, redbaron1982 said:

This makes me think that I have something wrong with my J. I can do only 500fpm above 5k feet. 

Yea, that’s below average for sure unless you have a super heavy plane. Below is a screenshot from FA of my F model at -2200lbs. it was indeed a cold day.  I was flying at 105mias into a strong wind out of the NW. It is admittedly at the upper end of the scale but you should not be far off.

D3A23CBB-E897-4A89-94DD-8AC0F5E6A6AC.png.be38a28da484ddf0643447a003ff9891.png

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I did this years ago, according to the POH the ceiling is 23,000’ for a J loaded to 2300 lbs, but I was struggling to get to 17000’ Turned out my cam was bad and wasn’t making power in 2 cylinders, ended up overhauling it but haven’t tried it since.
Im basicmed so now I’m legally limited to below 18000’.
BTW, OP’s speeds are in mixed units, GS in knots and TAS in mph…I would change that and make them both knots.

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18 hours ago, LANCECASPER said:

My IFR instructor had me take my mask off at FL240 and I kept it off for a few minutes and he had me do math problems and I wasn't having any difficulty and even a few minutes later it didn't seem like I was affected. He told me to get my mask back on and said that some people after showing no signs for awhile just black out and other people show more of a linear trend. The signs I was showing were the most dangerous since I might not see any sign of and O2 problem until it was critical.

That is why everyone who goes into the teens or higher REALLY needs to do a chamber ride.  Either a real pressure chamber or the travelling one that simulates by lower O2 %.

At 25,000, I have noticeable symptoms, but can perform for longer than the chamber guys wanted to wait.  But I can tell.

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In my chamber ride at Ft Rucker 40 years ago I was the first guy who wanted to go back on O2. I think I was functioning OK, I just didn’t like the feeling at all.

Going back on the mask gave me the opportunity to watch the others too.

I don’t remember how high we went, but I’ve been to Fl 250 in a crop duster, does that count? :) 

180 in a helicopter, the helicopter you could really feel the control difference and the rotor got rough.

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