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Correct Lycoming / Continental engine shutdown procedure (non electrical considerations)

The SIAI Marchetti SF.260 has a notch for mixture where you place the mixture control in the after take off checks, it is then left there until final approach checks.

On an MPL course I am familiar with, the engine is leaned as part of top of climb but to an SOP power setting and fuel flow. CHT and EGT is monitored but without the refinement of lean of peak etc.

I expect engine management SOPs are a rich diverse collection depending on the club/ATO.

Oxford (EGTK), United Kingdom

A_and_C wrote:

It’s interesting to see the bigger egos and sky gods pontificating about the shortcomings of the flight training industry but yet these people have no experience or responsibilities within that industry.

The commercial training industry has a mission to train pilots who will probably never again see an aircraft with a piston engine so they see no need to train the complicated end of piston engine management to a student who is close to being maxed out with other stuff.

There is simply no up side to getting into mixture adjustment and a very big down side if the student gets things wrong.

I can agree with that argument for MPL training where the student never gets a SEP (or MEP) rating. But not for PPL or CPL training where the student does get a SEP rating.

ESKC (Uppsala/Sundbro), Sweden

I am sure nobody disagrees with that. The practicalities are clear.

The problems start when one of the customers decides to use piston GA seriously But that is where EuroGA comes in

Administrator
Shoreham EGKA, United Kingdom

It’s interesting to see the bigger egos and sky gods pontificating about the shortcomings of the flight training industry but yet these people have no experience or responsibilities within that industry.

The commercial training industry has a mission to train pilots who will probably never again see an aircraft with a piston engine so they see no need to train the complicated end of piston engine management to a student who is close to being maxed out with other stuff.

There is simply no up side to getting into mixture adjustment and a very big down side if the student gets things wrong.

So rather than slagging off the commercial training industry you should remember that the days of the piston engined airliner are long gone and even in those days lowly pilots did not get to touch the mixture controls, engine management was the job of the flight engineer , pilots just pointed the aircraft in the right direction.

Please don’t consider the ‘Peak EGT’ reading as a redline, it is NOT.
The real limiting factor is the Internal Combustion Pressure ICP, we have no means of measuring that in our aircraft, but there is a very good proxy: the CHT.
The trouble with CHT is that is reacts very slowly while the EGT reacts in seconds.
So, you can use the EGT as a proxy for the CHT which is the best available proxy for the ICP.
You have to remember that there is an offset between the CHT and EGT curves, the hottest CHT is achieved at about 40° rich of peak EGT. At peak EGT, your CHTs are already considerably lower.
There is some considerable misinformation in the older POHs. Properly ROP needs to be richer than most POHs advise because the marketing department likes the better range at 50°ROP compared to richer.
In brief, use the EGT as a tool to navigate the curve and put the mixture in the optimum position (either for best power, best economy, etc). At 65% power of below, you cannot hurt the engine with the mixture.

EBKT

GA_Pete wrote:

WRT Leaning, having read lots of articles, some of which I even retain, I wouldn’t lean anything for cruise without the appropriate instrumentation.

Just read the POH to establish power settings.

For instance I know from the POH that in our TB10, 24" and 2400rpm at 2,000ft is pretty much 75% power. Below 75% you can do whatever you want with the mixture without risk: peak EGT, lean of peak, rich of peak – anything you like.

That is not to say that you can’t lean a bit above 75% power. The whole power/mixture/EGT/avoiding detonation thing is a continium, not a scale with only fixed points of safe and dangerous. The engine won’t explode if you pull the mixture back with the power above 75%, but a POH needs to be written in a black-and-white manner thus they just tell you the point at which it is safe to do anything at all.

We only have an analogue EGT gauge and that’s good enough for me. Once you know where on that scale your needle is when you’re running peak EGT at just less than 75% power in the cruise, then that point on the scale functions as your ‘redline’ for any other combo of MP/RPM/OAT/DA where you might not be sure exactly how much power the engine is developing.

EGLM & EGTN

I’m leaning now with Engine Monitoring.
But in consideration of your power setting enquiry, I’m wondering if you were thinking about the reduced risks of low power setting and leaning?
I imagine many club or group A/c with less powerful engines are run routinely not far from around 75%.
That’s just a guess though.

We used to run the 180hp Robin at 2500-2550 rpm always. That must be close to 80%.
Similarly other 172’s and PA28’s I’ve been in have been run the same. They can be quite slow otherwise.
At that setting the margins are reduced.

United Kingdom

GA_Pete wrote:

WRT Leaning, having read lots of articles, some of which I even retain, I wouldn’t lean anything for cruise without the appropriate instrumentation

What power setting do you usually have?

ESKC (Uppsala/Sundbro), Sweden

When I first learned to fly, three of the four instructors I learned from, were FrAtpl.
Prob no more real experience than a regular 100hr PPL.
WRT Leaning, having read lots of articles, some of which I even retain, I wouldn’t lean anything for cruise without the appropriate instrumentation.

United Kingdom

I commented on that video on YouTube saying that I was surprised to see they weren’t teaching leaning and engine management.

Got a fairly brusque reply saying I was making quite a leap with my assumption and that they flight plan based on the full-rich fuel burn. Not sure if the pilot in that video really knew what I meant, but then if nearly all his flying has been within the training scene then it’s quite possible he doesn’t really know how to lean properly. You can lean effectively even without instrumentation – it’s not as good – but still effective – and the PoH/Lycoming guidance expects you to.

EGLM & EGTN
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