Lean of peak ops, landing

[hubcap]

1 hour ago, Z W said:

 

It's probably still too lean to make full takeoff power, if I had to guess.  And verifying fuel flow when you start the takeoff roll is always a good idea too.  But setting your engine up to stall as some kind of a reminder to enrichen the mixture for takeoff doesn't sit right with me.  I prefer a checklist and good muscle memory.

I can tell you from experience that my taxi mixture will only give a little over 16gph if you try to takeoff…..just sayin. My full rich gives 23gph in takeoff mode. Fuel flow is part of my takeoff scan.

[carusoam]

Great conversation!

NA or TN’d there are some differences… and many similarities… in my O1….

1) I prefer to fly LOP.

2) Long body speeds as they are… I start slowing down a couple miles from the traffic pattern…

3) This gives the opportunity to have gear down, and T/O flaps deployed once in the white arc…

4) This is also the time I go into ROP mode… not full rich.

5) the LBs got a blue arc on the EGT gauge for climb power… a 100°F range… starting about 200°F ROP

6) the Acclaims have the G1000 with the white box instead… same range, same engine safety, same operability for the go-around…

 

7) Essentially my first Gumps occurs a bit earlier than the rest of the world…

8) And the mixture is now steady in the blue box…

9) In the traffic pattern the usual flaps and gumps checks… and full rich at my near SL airport….

 

Note: leaving the engine leaned from altitude… won’t be noticed until the plane is on the ground… it will stumble and die on roll out.

if you are fast on the mixture control it runs easily… 

if the prop stops turning… you start to wonder if the next start will be a hot, cold, or warm start… wondering if the plane’s momentum will carry you to the next turn off…  

 

Note for Dan… this is my NA IO550 experience for my O3 powered O1.  Consider using the white box on your G1000’s EGT/TIT sensor..(?)

going full rich at sea level the EGT will be lower than the white box… in a slight too rich zone…. But, realistically when we are turning 2700 rpm full rich is considered 30gph… (310 hp discussion) it’s hard to get there even at full rich…

The big difference from standard Mooneys… the EGT gauge is calibrated with real temperature readings, and an arc is ‘printed’ on the face of the instrument… that makes it really easy to put the engine in a safe ROP zone… not too rich, not too lean, no matter what altitude we are landing at…

the IO550s got a standard EGT sensor location for this important ship’s gauge.  A location machined in the exhaust’s 3 into 1 collector allowing for the calibration between sensor location and the instrument readings… where an 1/8” really changes the temp being displayed…

Oddly, for years… the G1000’s EGT display in the Ovations was marked TIT… it took a while before the software ever got updated… 

PP thoughts only, not a mechanic… or CFI.

Best regards,

-a-
 

Soooo many Mooneys currently have nice engine instruments, and their sensors installed in standard locations… it wouldn’t take much to have the blue box actually indicated on a JPI or EI device…

making absolute EGT readings totally useable… 

[PeteMc]

6 hours ago, Z W said:

I find it too easy to give it a little too much throttle while trying to taxi uphill and stall the engine

Interesting, maybe I'm not leaning as much as I think I am.    I used to fly frequently into 44N where you REALLY go up a hill to get to the restaurant and to the fuel pumps.  I never had a problem going up that hill, but maybe it was because it was a familiar hill and instinctively I put in just enough throttle to get up the hill. 

From memory I'll *guestimate* it was a good 45 degree hill, but I'll leave it to others that know 44N to correct me on how steep it really was.  

[Pinecone]

Do you lean for taxi to the point you have to richen to do your run up?

If so, then no, you would not lean that far on downwind.   If you can do your runup without going richer, then that is about right for the pattern.

[Danb]

8 hours ago, carusoam said:

Great conversation!

NA or TN’d there are some differences… and many similarities… in my O1….

1) I prefer to fly LOP.

2) Long body speeds as they are… I start slowing down a couple miles from the traffic pattern…

3) This gives the opportunity to have gear down, and T/O flaps deployed once in the white arc…

4) This is also the time I go into ROP mode… not full rich.

5) the LBs got a blue arc on the EGT gauge for climb power… a 100°F range… starting about 200°F ROP

6) the Acclaims have the G1000 with the white box instead… same range, same engine safety, same operability for the go-around…

 

7) Essentially my first Gumps occurs a bit earlier than the rest of the world…

8) And the mixture is now steady in the blue box…

9) In the traffic pattern the usual flaps and gumps checks… and full rich at my near SL airport….

 

Note: leaving the engine leaned from altitude… won’t be noticed until the plane is on the ground… it will stumble and die on roll out.

if you are fast on the mixture control it runs easily… 

if the prop stops turning… you start to wonder if the next start will be a hot, cold, or warm start… wondering if the plane’s momentum will carry you to the next turn off…  

 

Note for Dan… this is my NA IO550 experience for my O3 powered O1.  Consider using the white box on your G1000’s EGT/TIT sensor..(?)

going full rich at sea level the EGT will be lower than the white box… in a slight too rich zone…. But, realistically when we are turning 2700 rpm full rich is considered 30gph… (310 hp discussion) it’s hard to get there even at full rich…

The big difference from standard Mooneys… the EGT gauge is calibrated with real temperature readings, and an arc is ‘printed’ on the face of the instrument… that makes it really easy to put the engine in a safe ROP zone… not too rich, not too lean, no matter what altitude we are landing at…

the IO550s got a standard EGT sensor location for this important ship’s gauge.  A location machined in the exhaust’s 3 into 1 collector allowing for the calibration between sensor location and the instrument readings… where an 1/8” really changes the temp being displayed…

Oddly, for years… the G1000’s EGT display in the Ovations was marked TIT… it took a while before the software ever got updated… 

PP thoughts only, not a mechanic… or CFI.

Best regards,

-a-
 

Soooo many Mooneys currently have nice engine instruments, and their sensors installed in standard locations… it wouldn’t take much to have the blue box actually indicated on a JPI or EI device…

making absolute EGT readings totally useable… 

Hi Andrew great to be hearing from you.

Also I’m in the middle of a long trip, St Louis, Albuquerque, Las Vegas, Amarillo, now outside of Memphis. The controllers are keeping me extraordinarily high on approach to landing. So bad in Henderson in the heat and turbulence I had to go around, touched the runway way to fast and went around BTW WE ALL SHOULD PRACTICE THAT,,  pissed off the tower since it was one of their busiest days. That’s no excuse, but controllers should fly in small planes to have a clue we can’t slow as a jet does.

Anyway nice to hear from you A

 

DB 

[A64Pilot]

19 hours ago, PeteMc said:

Did you really mean "taxi mixture" while in the Downwind?  From what I've been taught (PPP and others) and told by multiple mechanics when I've asked, my "Taxi Mixture" is WAY TOO LEAN for the engine to operate in flight.  It is intentionally too lean to achieve Takeoff Power so I don't forget to go Full Rich when I do go to Takeoff.  

 

What your doing in my opinion is smart, people honestly lose their lives every so often taking off at a mixture setting that won’t support full power, and or damage their engine, at full power and sea level you can damage a Lycoming with improper mixture setting.

You would think that an experienced person when feeling the engine being sluggish would instantly push that red knob all the way in (assuming near sea level) but they don’t always, of course most of the time I’m sure they do, but you don’t read about almost accidents

The guy who includes fuel flow in his takeoff check is also smart in my opinion, that can save you from a bad experience.

@carusoam welcome back  

 

[jlunseth]

I wrote my own checklists because the pre-flight items are scattered all over in the POH for the 231, and because things are missing that should be in a checklist. My checklist is divided into sections, the last section used prior to takeoff being the "Before Takeoff" checklist. My Before Takeoff checklist includes mixture full rich, where it must always be for takeoff behind a turbocharged engine. I use the Before Takeoff section for every takeoff, meaning that even if I am doing pattern work, I land, taxi back, and get ready to take off, and I run that checklist every time. 

That said, there are times when it is possible to mess up even with a checklist. Typical would be, I line up for takeoff but there are a couple of aircraft in the pattern that the tower is going to land before I can go, so I am going to have to sit there for some time with the engine at idle. It is not good for the engine to sit at idle full rich, it can clog the plugs. So I might lean the engine out. When I do that, I leave my hand on the mixture knob to remind myself that I have to put the mixture back in full rich before I take off.

All that said, it still happens once a year that I go through all that and then something happens, tower gives me an amendment to a clearance for example and I need to get that into the GPS, so I take my hand off the mixture and forget to put it back in. If that happens I will see marvelously warm temperatures, especially TIT, on takeoff. I have a habit of checking MP and other settings during takeoff, because MP wants to increase somewhat as the 231 picks up speed and I don't want it to wander over 37", so I see the temp issues somewhere during or shortly after takeoff and I immediately shove the mixture in. Wish I were perfect, but that is how things work in my plane.

If you are well leaned out in a turbo, say you are having to do a go around and you forget the mixture knob, the plane simply won't develop full power for you. The condition is obvious and the cure is to immediately push the knob in, then you are good to go.

One difference between the turbo and the NA is that the turbo never lacks power during a takeoff or go around, there is more power than is really needed, even in the 231. A go around is never an emergency, the power is always there to get the aircraft well into the air. So unlike an NA which might have marginal takeoff power because of a density altitude issue, we have time in the turbo to get everything right, even if we made a mistake or failed to change the mixture immediately. Obviously it is not ideal to be in that position, but there is time and no need to panic unless you did something else really stupid, like grossly overload the aircraft or try to take off on an excessively short runway. 

[EricJ]

10 hours ago, carusoam said:

Best regards,

-a-

Good to see ya back!

[tmo]

1 hour ago, jlunseth said:

I take my hand off the mixture and forget to put it back in. If that happens I will see marvelously warm temperatures, especially TIT, on takeoff. I have a habit of checking MP and other settings during takeoff, because MP wants to increase somewhat as the 231 picks up speed

With all due respect, and I truly have lots of it for you, perhaps leaning _more_ (especially when idling) would be a good option, this way you are sure to have the engine idle OK but stumble way before you get anywhere close to full power, allowing you to either go full rich or abort the roll. I tend to lean my (non intercooled) 231 to around 2gph for taxi.

I started consciously NOT going full rich for landing because in my plane it will cause backfire, especially on hot days, which is even worse for a TC engine than a NA one. That said, I don't leave it very lean in case I need a bit of power to save my landing, which is more often than I would like to admit to.

On a go-around I made it a habit to never go to full power (throttle) immediately. I add enough to get it flying, re-trim, and only then push the throttle to 40". That written, I've never had a real go-around, so I can't say how this will hold up in real life.

ps. care to share your checklists?

[PeteMc]

4 hours ago, A64Pilot said:

The guy who includes fuel flow in his takeoff check is also smart in my opinion, that can save you from a bad experience.

Very true!  A full scan is the only way to do it!

 

[carusoam]

+1 for for the T/O quick check of power production…

1) MP  (O3 somewhere near 29”, near SL.

2) RPM (O3 2700)  if using 280hp, 2500rpm

3) FF (O3 somewhere over 28 to 30 gph)  if using 280hp, somewhere over 25gph (?)

 

The first two are enough to know your T/O calculations are going to work….

The third one indicates the internal cylinder cooling is working as expected…

Back in the day… trainers didn’t come with FF gauges… so this detail wasn’t considered…

There is a lot to do when racing from zero to Vr… it really helps to know you are going to look for these details before pushing the throttle in… 

 

PP thoughts only, not a CFI…

Best regards,

-a-

[Fly Boomer]

6 minutes ago, carusoam said:

+1 for for the T/O quick check of power production…

1) MP  (O3 somewhere near 29”, near SL.

2) RPM (O3 2700)  if using 280hp, 2500rpm

3) FF (O3 somewhere over 28 to 30 gph)  if using 280hp, somewhere over 25gph (?)

 

The first two are enough to know your T/O calculations are going to work….

The third one indicates the internal cylinder cooling is working as expected…

Back in the day… trainers didn’t come with FF gauges… so this detail wasn’t considered…

There is a lot to do when racing from zero to Vr… it really helps to know you are going to look for these details before pushing the throttle in… 

 

PP thoughts only, not a CFI…

Best regards,

-a-

^^^THIS^^^

My numbers are more like 38/2650/35 or something very close but, whatever they are, it's the most important thing to check after full power is applied.

[cujet]

My before landing checklist is about as simple as possible. Red, Blue, Green. That would be: Mixture, Prop and Gear down green lights. Midfield downwind or 2 miles out. My IO360 will misfire terribly if I have to add power to, for example, correct a sink rate. 

My intent was to keep things as simple as possible, while still using a checklist. 

[RobertGary1]

On 9/26/2023 at 7:28 AM, Danb said:

When flying lean of peak upon approach to landing when do you go full rich. 

No. I stay lean. I have the quadrant so I can add throttle and enriched with one hand at once. Going full rich for landing means you’ll need to clean your plugs often. 

[jlunseth]

10 hours ago, tmo said:

With all due respect, and I truly have lots of it for you, perhaps leaning _more_ (especially when idling) would be a good option, this way you are sure to have the engine idle OK but stumble way before you get anywhere close to full power, allowing you to either go full rich or abort the roll. I tend to lean my (non intercooled) 231 to around 2gph for taxi.

I started consciously NOT going full rich for landing because in my plane it will cause backfire, especially on hot days, which is even worse for a TC engine than a NA one. That said, I don't leave it very lean in case I need a bit of power to save my landing, which is more often than I would like to admit to.

On a go-around I made it a habit to never go to full power (throttle) immediately. I add enough to get it flying, re-trim, and only then push the throttle to 40". That written, I've never had a real go-around, so I can't say how this will hold up in real life.

ps. care to share your checklists?

Might try that, it is a good idea.

I will see if I can upload my checklists to the site. Some of it is specific to instrumentation I have that others may not. I wrote it in Word so you could edit it to your heart’s content - if I can upload it. It was on the site at one time, years ago, but has probably disappeared.

[Z W]

I'm not jlunseth, but I re-did my checklist this year and am pretty happy with how it turned out.  I copied it from a corporate pilot's checklist that he made for a Cessna 441, so I can't take all the credit.  Printed it front-and-back and laminated it.  Two copies in the plane - one for the pilot and one for the copilot. 

My goal was to use it to fly more like a professional commercial pilot, and to be able to have my co-pilot read it to me like a commercial two-pilot crew.  With a new panel and autopilot in the plane, updating the checklist was really necessary.  In particular I've found the "Before Taxi" section is really great for making sure my flight director, altitude / heading bugs, autopilot mode, etc. are how I want them before leaving the ramp, so I'm not fiddling with all of that at the end of the runway, or getting in a hurry and taking off without it all set.

Would love any suggestions on what it's missing or how it could be better. 

PDF attached, Word version here (can't upload to Mooneyspace):

https://1drv.ms/w/s!AjJPoJhv9yifmoFH22Jlj0A2ncinjQ?e=0vCmrO

Note - downloading the Word version seems necessary to preserve the dual column layout.  It opens weird in my web browser, at least, but opens fine if I re-download it to my computer.

 

Checklist - M20K - v1 - 11.10.2022.pdf

[midlifeflyer]

As already mentioned, "full rich" is for flat landers. Do that in some parts of the country and your "go-around" will be "go to the ground" when the engine quits as you raise the nose to climb out. Not pretty. The two reasons for enrichening to an appropriate setting for the altitude are landing and go-around. (Some tend to discount the landing, but my D-Alt experience says don't.

FWIW, my technique is pretty basic. Along with reducing throttle in stages to reach my target MP for approaches, I adjust mixture in stages too. If you have some technique to do it accurately, such as maintaining target EGT, wonderful, but that ~3000' mentioned in the manual gives you a clue you don't have to be perfect.  

[LANCECASPER]

On 9/26/2023 at 9:28 AM, Danb said:

When flying lean of peak upon approach to landing when do you go full rich. 

This question might have been better in the “Acclaim Owners” forum since the answer might be model specific. (Whether you have a Continental or Lycoming, or whether you have a Turbo or not, etc.)

I’m going to guess that some Acclaim owners have experienced the exact same thing you and I both recently experienced. It would be interesting to hear what @exM20K and @mike_elliott have to say since they both have a lot of time in M20TNs.

[A64Pilot]

13 hours ago, RobertGary1 said:

No. I stay lean. I have the quadrant so I can add throttle and enriched with one hand at once. Going full rich for landing means you’ll need to clean your plugs often. 

It shouldn’t, in fact an IO-360 should be able to taxi around extensively at full rich and not foul the plugs and be on a long approach full rich without fouling assuming the idle mixture is correctly set of course.

It may foul plugs if they need cleaning anyway, a very carboned up plug will foul much easier than a clean one.

If it were common for plugs to foul from idling or especially on approach, then trainers would all be fouled most of the time and checklists would have been written long ago to lean for taxi and approach, some of the big round motors I think may have been but I don’t fly them so I don’t know for sure, some of those were quite complex to operate.

Remember we have every possible level of experience here, some are very new to flying and have their hands full as it is with a complex aircraft.

I think it prudent myself that we preach adherence to the POH myself. It’s tough to be wrong if you followed the checklist and sometimes tough to justify not doing so, I’m talking of course if there is an accident or incident of course. But it’s a free Country and it’s your airplane, so

A quick Google found this, there are several hits, this is just the first one, an experienced person wouldn’t have made this mistake I don’t think.

https://generalaviationnews.com/2019/10/01/failure-to-enrich-mixture-ends-in-accident/

Then there is this opinion

https://pilotworkshop.com/tips/mixture-during-descent/

[PT20J]

Leaning for taxi became all the rage when 80 octane went away and lower compression engines had to use 100LL. The extra lead combined with combustion chamber temperatures too low at low power to activate the lead scavenger led to fouled plugs. The purpose of leaning is to raise the combustion temperature to better scavenge the lead.

An engine designed for 100 octane shouldn’t have a problem running rich during taxi. Leaning doesn’t hurt, but it’s a good way to kill a turbocharged engine if you forget to set it back to full rich before takeoff.

Skip

[Shadrach]

14 hours ago, RobertGary1 said:

No. I stay lean. I have the quadrant so I can add throttle and enriched with one hand at once. Going full rich for landing means you’ll need to clean your plugs often. 

Our F model was never leaned for taxi until I started flying it in 2002. Never had issues with lead fouling. Indeed the Lyc IO360 is very unlikely to suffer from lead scavenging issues in taxi. It has inherently good F/A distribution to all cylinders and some of the highest compression pistons in the certified GA fleet. No need to lean at reasonable DAs. I worry more about lead fouling in winter at low power settings as it can be challenging to keep some CHTs above 280°.

[mike_elliott]

Personally, I set up for go around by going rich when I have the field made. 

[RobertGary1]

On 9/29/2023 at 9:37 AM, A64Pilot said:

It shouldn’t, in fact an IO-360 should be able to taxi around extensively at full rich and not foul the plugs and be on a long approach full rich without fouling assuming the idle mixture is correctly set of course.

It may foul plugs if they need cleaning anyway, a very carboned up plug will foul much easier than a clean one.

If it were common for plugs to foul from idling or especially on approach, then trainers would all be fouled most of the time and checklists would have been written long ago to lean for taxi and approach, some of the big round motors I think may have been but I don’t fly them so I don’t know for sure, some of those were quite complex to operate.

Remember we have every possible level of experience here, some are very new to flying and have their hands full as it is with a complex aircraft.

I think it prudent myself that we preach adherence to the POH myself. It’s tough to be wrong if you followed the checklist and sometimes tough to justify not doing so, I’m talking of course if there is an accident or incident of course. But it’s a free Country and it’s your airplane, so

A quick Google found this, there are several hits, this is just the first one, an experienced person wouldn’t have made this mistake I don’t think.

https://generalaviationnews.com/2019/10/01/failure-to-enrich-mixture-ends-in-accident/

Then there is this opinion

https://pilotworkshop.com/tips/mixture-during-descent/

In the aircraft I teach in there is a big note to lean immediately after engine start and after clearing the runway because they’ve had issues with fouling. I used to have fouling when I first bought my Mooney 20 years ago because I wasn’t ground leaning. I’ve never flown any injected fixed wing where we taxi with full rich. Are there fbos that have students do that?