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CHTs - way too hot yesterday during missed approach


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Well, I messed up yesterday.

I was flying IFR to Lake Placid and had no idea what the weather was over Lake Placid (since it doesn't report wx), but nearby Saranac Lake was reporting IFR ceilings. I knew Lake Placid was in a bowl and often times is VFR when nearby airports are IFR. I kept calling Unicom to ask about weather conditions over the field, but no one answered since it was before 9am.

Boston center asks me what approach I want and I ask for the Rnav 14 into LKP and get down to minimums and I'm in the soup hand flying. There are peaks taller than me around me that I can't see and I'm somewhat uncomfortable, although I'm dead center on the approach. At MAP, I'm still in the soup so I go missed which is a climbing right turn to 5000 from 3320. Well, in that short climb up to 2000ft, my CHTs spiked to about 435 (well the hottest cylinder anyway, the others ones were probably 404, etc) (redline is 450) in the climbing right turn.

I climbed at VY because I just wasn't comfortable being in the soup and having peaks higher than me around. I stayed dead center on approach the whole time, but didn't dare put my nose down too much because it was like 90F and my climb rate was otherwise anemic. I got the CHTs under control after reaching 5000ft, but felt so bad, especially since I just recently overhauled the engine on the bird. However, I don't think a minute at these CHTs really hurt anything (or at least that is what I'm telling myself).

I then fly over to LKP and sure enough, I could see the airport and did a spiral descent down. Well, here's another mistake: I was a little too high on final and initiated a slip. I touched down, but the airplane bounced 3-4 times before settling down. I should have gone around after the first bounce, but I was afraid of getting the engine super hot again in the climb (would have been fine it's only a thousand feet and I'm VFR at this point) and missing our ride out of the airport (that should never stop me from going around!). I have over 400 hours in this plane and I think it's the first time I bounced her.

Luckily, nothing was damaged except my pride and ego in that landing, but jeez...I couldn't stop thinking about it for the whole day.

Lessons learned:
1) When flying to LKP, before initiating an instrument approach, go direct field and see if it's VFR there (if Unicom doesn't answer). Maybe avoid shooting an approach in if it's an extensively hot day with high density altitude.

2) Never hesitate to go around because of external pressures. I'm happy there was no prop strike and only my ego was bruised, but it could have been worse.

3) @Sabremech - maybe your cowl would fix the higher CHTs on these Vintage birds? ;)

Edited by AlexLev
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1 hour ago, kmyfm20s said:

Did you go full rich mixture on your missed? You mentioned you recently overhauled the engine. Have yourTakeoff fuel flows been correct?

@kmyfm20s I would hope I was full rich during the approach, although I cannot specifically remember right now. I have a carb engine and they told me it was set as "too rich" causing the intake port to be all caked up with excessive carbon. I think they set it a little less, at the consequence of a little higher CHTs but I generally can keep it below 400F during climbouts. On the hotter days, I just need to be super conscious of it and can't have any ground idle time, which means getting clearance ahead of time, loading into 430 before starting engine, etc.

Edited by AlexLev
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Red line is 500, normal operating is up to 450.

Those temps don't seem all that high in the climb. It is summer after all. Just make sure you are full rich. Check your baffling and make sure it is in good shape.

You would do better worrying about flying your missed correctly than CHTs below red line.

BTW

How did you do the missed over the airport and not see it yet see it from 2000 AGL?

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4 minutes ago, steingar said:

Something I don’t get about all this. Everyone has engine monitors and sees all this stuff.  But these engines have been tooling away in these airframes since the early 60’s.  How bad can it be?

Ignorance is bliss - really, it is!

Before I had an engine monitor my temps were just fine!

Before I had Foreflight and a Stratus, I was the only plane in the sky. I could fly along just looking out the window without a care in the world. Now it is like a minefield out there!

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1 hour ago, N201MKTurbo said:

Red line is 500, normal operating is up to 450.

Those temps don't seem all that high in the climb. It is summer after all. Just make sure you are full rich. Check your baffling and make sure it is in good shape.

You would do better worrying about flying your missed correctly than CHTs below red line.

BTW

How did you do the missed over the airport and not see it yet see it from 2000 AGL?

If you look at the approach plate for LKP, https://resources.globalair.com/dtpp/globalair_09371r14.pdf - the MAP is not over the airport. LKP is in a bowl in between two mountains and often times is clear where everything else may be fogged in, so even though I was IMC at MAP, LKP itself only had a few clouds (but I didn't get that information until I was flying the missed, since the airport wasn't staffed until that point).

And yea - I noticed my CHTs high but at the moment didn't prioritize that info just to make sure I didn't mess up the missed approach. 

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You mentioned pitching for Vy on the missed. But consider, what is the min required climb rate to ensure terrain separation and what was your rate? Very possibly you were pitching far steeper than necessary.


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It looks like you could have flown the whole missed approach at MDA without hitting anything.

You might consider setting your IPad to sectional and zoom it way in during the approach so you can consult it easily to reassure yourself that you have terrain separation.

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Its a little different for us turbo guys, but it is a constant struggle to get mechanics to set the fuel flow rich enough.  They always, always seem to want to set it a little on the lean side.  A little on the rich side is better, we do have a red knob that let's us lean the engine out, but if the fuel flow is set too low there is nothing we can do except accept the higher CHT's.

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Alex @N201MKTurbo is correct - red line on our engines is 500. I set my secondary alarm on my JPI to 450.  430s on #4 and sometimes #2 in my bird in summer climb is commonplace.  Not desirable, but sometimes unavoidable.  Worst I have ever seen is 440 - coincidentally when told to pitch steep on a missed approach during IR training.  When working hard in IMC, I think it may be best to ignore the temps  and fly the plane.  I have worked on getting my temps down  ad nauseam and am convinced the only C/G model owners  with the doghouse who don't have this problem in climb are the ones without an engine monitor ;)  Does your G have movable cowl flaps BTW?  They are fixed on my bird, which does not help.  

Lake Placid IFR down to minimums might be as hairy as "mountain flying" on the east coast gets.  I certainly understand the urge to pitch for best angle getting out of there - as a new pilot a few years ago it made me a little nervous going there in clear weather.  It will take me some time before I have the guts to try it in solid IMC - you are way ahead of me.  

 

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I am concerned that you were getting inadequate fuel flow in the climb out. You should be sure 1) that the system delivers about 16 gph full rich, full throttle and 2) that you push in the red knob when you push in the throttle. The engine can and will overheat if excess cooling fuel it not there when you go balls to the wall.  

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12 minutes ago, DXB said:

Alex @N201MKTurbo is correct - red line on our engines is 500. I set my secondary alarm on my JPI to 450.  430s on #4 and sometimes #2 in my bird in summer climb is commonplace.  Not desirable, but sometimes unavoidable.  Worst I have ever seen is 440 - coincidentally when told to pitch steep on a missed approach during IR training.  When working hard in IMC, I think it may be best to ignore the temps  and fly the plane.  I have worked on getting my temps down  ad nauseam and am convinced the only C/G model owners  with the doghouse who don't have this problem in climb are the ones without an engine monitor ;)  Does your G have movable cowl flaps BTW?  They are fixed on my bird, which does not help.  

Lake Placid IFR down to minimums might be as hairy as "mountain flying" on the east coast gets.  I certainly understand the urge to pitch for best angle getting out of there - as a new pilot a few years ago it made me a little nervous going there in clear weather.  It will take me some time before I have the guts to try it in solid IMC - you are way ahead of me.  

 

Cowl flaps are fixed unfortunately on the G as well. And regarding Lake Placid: it's definitely a strange airport, I did my initial IFR cross country with my instructor there and have had one more instrument approach into it before when there were clouds before, but last time I actually broke out and saw the field.

This time I was in solid IMC and even though I was in no danger of hitting any obstacles and having ForeFlight open with the terrain page would have probably helped ease my discomfort, so that's a good tip -- I still wanted to climb as much as possible as quickly as possible on the missed.

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Yeah Piseco NY this weekend was almost 100F ambient and I suspect everyone that climbed out that general area probably saw temps on the upper range of the normal. By the way the alloy used for the head part of these late model cylinder assemblies in these engines is RR350 or a close derivative thereof for most manufacturers and although it also is not immune to high temperature creep (most high strength aluminum alloys fare alot worse) it will handle short time excursions into the 425 and 450 range very well "in relative terms". I am not recommending longer exposures to temps above about 200C (400F) but the time period you are describing is not something to loose sleep over. Good job in your decision matrix.

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I used to fly an M20C and for me, reducing RPM just a little bit would help with high CHT's.  I would still run full throttle full rich, but reducing the RPM to 2550 or so, would knock 20 degrees off my CHT's.

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It looks like you could have flown the whole missed approach at MDA without hitting anything.
You might consider setting your IPad to sectional and zoom it way in during the approach so you can consult it easily to reassure yourself that you have terrain separation.


The reason the pucker factor on this approach goes up a bit is that the hills behind the lower hills near the airport are about 1,000 above you. When you start your missed, you definitely feel like you are climbing out of a bowl. And I can appreciate Alex’s desire to climb more aggressively. If you follow the missed, you’ll be above the lower hills but you certainly see the ones that are higher.

If I remember correctly, this is the same airport the Mooney owner and his college aged daughter and another passenger were killed on an aborted landing.



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Cowl flaps are fixed unfortunately on the G as well. And regarding Lake Placid: it's definitely a strange airport, I did my initial IFR cross country with my instructor there and have had one more instrument approach into it before when there were clouds before, but last time I actually broke out and saw the field.
This time I was in solid IMC and even though I was in no danger of hitting any obstacles and having ForeFlight open with the terrain page would have probably helped ease my discomfort, so that's a good tip -- I still wanted to climb as much as possible as quickly as possible on the missed.


The latest version of ForeFlight will give you an automatic terrain/obstacle warning no matter what page you are in. You have to set that in settings. Pretty cool actually. It popped up for me on a approach to an airport with a very tall antennae near by. Most folks with a C equipped with an engine monitor will tell you they have seen 435 more than once. 1400 hours on mine and I’ve only had an engine monitor for 6 of the 7 years I’ve owned her so I’m sure it’s seen plenty of 435’s and higher before that. That being said, if I climb at 120 I’ll be under 400 even in hot summer days and mostly under 380. Climbing at Vy will take you over 400 during the summer without a doubt on most Cs. Your situation was a bit different in that you were climbing with terrain nearby in IMC. Just make sure you are full rich and I would not worry about an occasional 435 hot climb. If it were that bad my engine would be in pieces and it is still performing strong.


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I’m puzzled why you found the need to climb so aggresively. Going missed from your 3320 MDA through the missed procedure you are better than 1000 feet above any surrounding terrain. I wouldn’t worry about your CHTs. They were not excessive.

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1 hour ago, Hector said:

That being said, if I climb at 120 I’ll be under 400 even in hot summer days and mostly under 380.

I find this point to be generally true  in my C if I pitch for 120 immediately after cleaning up the plane and also depart shortly after start up.  But I can usually only accomplish a quick enough departure vfr from a nontowered field.  Any significant delay with taxiing, waiting, copying clearance, configuring avionics, holding for release, etc. pretty much dooms me to 430s CHTs on 1-2 cylinders in the summer until I climb a few thousand feet.  

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3 hours ago, Bob_Belville said:

I am concerned that you were getting inadequate fuel flow in the climb out. You should be sure 1) that the system delivers about 16 gph full rich, full throttle and 2) that you push in the red knob when you push in the throttle. The engine can and will overheat if excess cooling fuel it not there when you go balls to the wall.  

Unfortunately, only a TCM engine has a means of adjusting fuel flow.  You would need a well worn main jet in a carburetor to get more fuel flow.  Bendix fuel injection has the same limitation, not field adjustable.

Clarence

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The Owners Manual for my C says 18.2 gph at sea level, WOT and 2700. Sixteen isn't nearly enough. Confirm your fuel flow.

It also shows 670-870 fpm climb at 3000 msl and 97 mph. So no need to panic. If DA is a little high, 580-780 fpm at 5000 msl and 95 mph. These are for 2575 and 2200 lbs.

Finally, remember both Mooney and Lycoming are built strong and overengineered.

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16 minutes ago, M20Doc said:

Unfortunately, only a TCM engine has a means of adjusting fuel flow.  You would need a well worn main jet in a carburetor to get more fuel flow.  Bendix fuel injection has the same limitation, not field adjustable.

Clarence

Aren't there several different dash numbers for the carb jets that can be swapped out to change fuel flow in our O-360s?

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