Turbo 182: correct mixture for final approach at high altitude?

[Barry Klein]

We took a newer 182 turbo to a 7000' elevation airport yesterday and
the engine quit at the end of the landing roll. I'm sure the mixture
was way too rich. It restarted without incident, glad we were on the
ground! We had the mixture set about 100 deg rich of peak TIT for
cruise at 9500. How should we have found the correct mixture setting
for power-off final approach, when the turbo is basically adding no
boost and we are at high density altitude? This is not addressed in
the POH. It does say full rich on takoff regardless of airport
elevation. Later that day, when taxiing for takoff, we set 1200 rpm
and leaned for peak rpm, mixture knob was out 1.5-2 inches to achieve
this.

When we returned home to 800' elevation, we checked the idle speed at
full rich, it was about 500 rpm, is this too low?


Thanks,
Barry

[Michael 182]

I'm not sure the engine quit because the mix was too rich. When you took off
you were boosting the engine to 31 inches (I assume) - effectively sea level
performance. That's why you run it full rich. There may be some other
problem here.

Michael



"Barry Klein" > wrote in message
om...
> We took a newer 182 turbo to a 7000' elevation airport yesterday and
> the engine quit at the end of the landing roll. I'm sure the mixture
> was way too rich. It restarted without incident, glad we were on the
> ground! We had the mixture set about 100 deg rich of peak TIT for
> cruise at 9500. How should we have found the correct mixture setting
> for power-off final approach, when the turbo is basically adding no
> boost and we are at high density altitude? This is not addressed in
> the POH. It does say full rich on takoff regardless of airport
> elevation. Later that day, when taxiing for takoff, we set 1200 rpm
> and leaned for peak rpm, mixture knob was out 1.5-2 inches to achieve
> this.
>
> When we returned home to 800' elevation, we checked the idle speed at
> full rich, it was about 500 rpm, is this too low?
>
>
> Thanks,
> Barry

[Michael 182]

Sorry - I read your initial post incorrectly - realize now you were talking
landing roll. I generally just keep adding a half turn or so to the mix
about every 1000 feet as I descend. By experience I know approximately where
the mix will be on the ground around Denver - about 1.5 inches out. Be ready
to push in the mix along with the power if you have to go around, however.

I added a placard and adjusted my checklist to add mix-full in to my takeoff
checklist. A few times I leaned for run up and proceeded to take off with
the mix an inch out - really affects the climb out.


Michael



"Michael 182" > wrote in message
news:iGjMb.25464$Rc4.98379@attbi_s54...
> I'm not sure the engine quit because the mix was too rich. When you took
off
> you were boosting the engine to 31 inches (I assume) - effectively sea
level
> performance. That's why you run it full rich. There may be some other
> problem here.
>
> Michael
>
>
>
> "Barry Klein" > wrote in message
> om...
> > We took a newer 182 turbo to a 7000' elevation airport yesterday and
> > the engine quit at the end of the landing roll. I'm sure the mixture
> > was way too rich. It restarted without incident, glad we were on the
> > ground! We had the mixture set about 100 deg rich of peak TIT for
> > cruise at 9500. How should we have found the correct mixture setting
> > for power-off final approach, when the turbo is basically adding no
> > boost and we are at high density altitude? This is not addressed in
> > the POH. It does say full rich on takoff regardless of airport
> > elevation. Later that day, when taxiing for takoff, we set 1200 rpm
> > and leaned for peak rpm, mixture knob was out 1.5-2 inches to achieve
> > this.
> >
> > When we returned home to 800' elevation, we checked the idle speed at
> > full rich, it was about 500 rpm, is this too low?
> >
> >
> > Thanks,
> > Barry
>
>

[john smith]

Barry Klein wrote:
>
> How should we have found the correct mixture setting
> for power-off final approach, when the turbo is basically adding no
> boost and we are at high density altitude?

Did you enrichen the mixture between cruise and landing?
There should have been no reason to. As you reduce altitude and MP, the
mixture will enrichen with decrease in altitude. Had you need to do a go
around, the cruise mixture would have been sufficient for a full power
go-around.

[Michael 182]

Are you sure about this? I always have to enrichen the mixture as I decrease
altitude.

Michael


"john smith" > wrote in message
...
> Barry Klein wrote:
> >
> > How should we have found the correct mixture setting
> > for power-off final approach, when the turbo is basically adding no
> > boost and we are at high density altitude?
>
> Did you enrichen the mixture between cruise and landing?
> There should have been no reason to. As you reduce altitude and MP, the
> mixture will enrichen with decrease in altitude. Had you need to do a go
> around, the cruise mixture would have been sufficient for a full power
> go-around.

[Peter Duniho]

"john smith" > wrote in message
...
> [...] Had you need to do a go
> around, the cruise mixture would have been sufficient for a full power
> go-around.

You do understand that he's talking about a turbocharged engine, right?
Generally speaking, full rich is the correct mixture setting for a
turbocharged piston engine, for full-power takeoffs regardless of altitude.

Pete

[Peter Duniho]

"Barry Klein" > wrote in message
om...
> We took a newer 182 turbo to a 7000' elevation airport yesterday and
> the engine quit at the end of the landing roll. I'm sure the mixture
> was way too rich. It restarted without incident, glad we were on the
> ground!

My airplane, with a Lycoming TIO-540, will do the same thing at high
altitude airports if the mixture is set full-rich prior to touchdown.

Operationally, I simply leave the mixture alone during descent. Given that
descents are usually made at reduced power, theoretically I could even lean
the mixture during the descent (opposite of what you'd normally do with a
normally aspirated engine at power settings near cruise), but I just keep an
eye on the turbine inlet temperature and normally no change in mixture
setting is required to keep the TIT in the ballpark of 1500 F.

During a go-around, it is critical that I remember to push the mixture
full-rich, but since it is just as critical that the engine not stop until I
am actually done flying the airplane, this is an acceptable trade-off.

I also need to keep the mixture lean while taxiing, otherwise I get fouled
plugs. I asked my mechanic about both issues (since they seem related) and
he verified that the idle mixture is correct for my installation. It just
runs rich at or near idle power unless the mixture is manually adjusted. At
higher density altitudes, idle mixture is so rich it will flood the engine
and make it stop.

> [...] Later that day, when taxiing for takoff, we set 1200 rpm
> and leaned for peak rpm, mixture knob was out 1.5-2 inches to achieve
> this.

I assume you mean you just did this as a test during taxi, and that you
returned the mixture to full rich before takeoff?

> When we returned home to 800' elevation, we checked the idle speed at
> full rich, it was about 500 rpm, is this too low?

Sounds about right, but I don't know the specifics for that engine. It
might be that it's supposed to be higher. I would ask the mechanic
maintaining the aircraft if he has the engine manual for the engine
installed, and then you can read in that what the actual numbers should be.

Pete

[Barry Klein]

Thanks everyone for the info. This was my first flight in a turbo, my
experience is with non-turbo 182s.
My buddy was in the left seat for the landing, 6750', about 50 deg F. I'm
not sure what he did for final approach,
may have gone to full rich.

Ragards,
Barry
----- Original Message -----
From: "Peter Duniho" >
Newsgroups: rec.aviation.piloting
Sent: Sunday, January 11, 2004 3:01 PM
Subject: Re: Turbo 182: correct mixture for final approach at high altitude?


> "Barry Klein" > wrote in message
> om...
> > We took a newer 182 turbo to a 7000' elevation airport yesterday and
> > the engine quit at the end of the landing roll. I'm sure the mixture
> > was way too rich. It restarted without incident, glad we were on the
> > ground!
>
> My airplane, with a Lycoming TIO-540, will do the same thing at high
> altitude airports if the mixture is set full-rich prior to touchdown.
>
> Operationally, I simply leave the mixture alone during descent. Given
that
> descents are usually made at reduced power, theoretically I could even
lean
> the mixture during the descent (opposite of what you'd normally do with a
> normally aspirated engine at power settings near cruise), but I just keep
an
> eye on the turbine inlet temperature and normally no change in mixture
> setting is required to keep the TIT in the ballpark of 1500 F.
>
> During a go-around, it is critical that I remember to push the mixture
> full-rich, but since it is just as critical that the engine not stop until
I
> am actually done flying the airplane, this is an acceptable trade-off.
>
> I also need to keep the mixture lean while taxiing, otherwise I get fouled
> plugs. I asked my mechanic about both issues (since they seem related)
and
> he verified that the idle mixture is correct for my installation. It just
> runs rich at or near idle power unless the mixture is manually adjusted.
At
> higher density altitudes, idle mixture is so rich it will flood the engine
> and make it stop.
>
> > [...] Later that day, when taxiing for takoff, we set 1200 rpm
> > and leaned for peak rpm, mixture knob was out 1.5-2 inches to achieve
> > this.
>
> I assume you mean you just did this as a test during taxi, and that you
> returned the mixture to full rich before takeoff?

Yes, we did this just to get a smooth idle for taxi. We went full rich on
the takeoff roll and climbed out to 8500' nicely.
I just mentioned this to demonstrate how lean we needed to go to get to the
best power setting at 1200 rpm.

>
> > When we returned home to 800' elevation, we checked the idle speed at
> > full rich, it was about 500 rpm, is this too low?
>
> Sounds about right, but I don't know the specifics for that engine. It
> might be that it's supposed to be higher. I would ask the mechanic
> maintaining the aircraft if he has the engine manual for the engine
> installed, and then you can read in that what the actual numbers should
be.
>
> Pete
>
>

[Jeff]

I have a turbo arrow, my POH also says full rich on take off. Thats what
I use on take off and landing. I do not adjust the miicture untill I am
at cruise altitude.
how come you didnt just set it to full rich like the book suggested?

you either have a fixed or an automatic wastegate, the automatic
wastegate will use the turbo as needed. the key is to fly as the book
says to fly and not try to out guess the airplane.

Barry Klein wrote:

> We took a newer 182 turbo to a 7000' elevation airport yesterday and
> the engine quit at the end of the landing roll. I'm sure the mixture
> was way too rich. It restarted without incident, glad we were on the
> ground! We had the mixture set about 100 deg rich of peak TIT for
> cruise at 9500. How should we have found the correct mixture setting
> for power-off final approach, when the turbo is basically adding no
> boost and we are at high density altitude? This is not addressed in
> the POH. It does say full rich on takoff regardless of airport
> elevation. Later that day, when taxiing for takoff, we set 1200 rpm
> and leaned for peak rpm, mixture knob was out 1.5-2 inches to achieve
> this.
>
> When we returned home to 800' elevation, we checked the idle speed at
> full rich, it was about 500 rpm, is this too low?
>
> Thanks,
> Barry

[Jeff]

is this a turbo charged engine also?
I have taken off with a DA of 8800 ft, full rich and not had a problem in my
T-arrow
I use full rich on take off and landing, as my POH says to do.

Peter Duniho wrote:
My airplane, with a Lycoming TIO-540, will do the same thing at high

> altitude airports if the mixture is set full-rich prior to touchdown.
>
> Operationally, I simply leave the mixture alone during descent. Given that
> descents are usually made at reduced power, theoretically I could even lean
> the mixture during the descent (opposite of what you'd normally do with a
> normally aspirated engine at power settings near cruise), but I just keep an
> eye on the turbine inlet temperature and normally no change in mixture
> setting is required to keep the TIT in the ballpark of 1500 F.
>
> During a go-around, it is critical that I remember to push the mixture
> full-rich, but since it is just as critical that the engine not stop until I
> am actually done flying the airplane, this is an acceptable trade-off.
>
> I also need to keep the mixture lean while taxiing, otherwise I get fouled
> plugs. I asked my mechanic about both issues (since they seem related) and
> he verified that the idle mixture is correct for my installation. It just
> runs rich at or near idle power unless the mixture is manually adjusted. At
> higher density altitudes, idle mixture is so rich it will flood the engine
> and make it stop.
>
> > [...] Later that day, when taxiing for takoff, we set 1200 rpm
> > and leaned for peak rpm, mixture knob was out 1.5-2 inches to achieve
> > this.
>
> I assume you mean you just did this as a test during taxi, and that you
> returned the mixture to full rich before takeoff?
>
> > When we returned home to 800' elevation, we checked the idle speed at
> > full rich, it was about 500 rpm, is this too low?
>
> Sounds about right, but I don't know the specifics for that engine. It
> might be that it's supposed to be higher. I would ask the mechanic
> maintaining the aircraft if he has the engine manual for the engine
> installed, and then you can read in that what the actual numbers should be.
>
> Pete

[Mark Mallory]

Peter Duniho wrote:

> You do understand that he's talking about a turbocharged engine, right?
> Generally speaking, full rich is the correct mixture setting for a
> turbocharged piston engine, for full-power takeoffs regardless of altitude.


'Generally speaking', but not necessarily. Full-rich is the correct takeoff
setting for a FUEL-INJECTED engine regardless of altitude, but *not* for a
CARBURETED engine.

Most turbocharged engines are injected, but not all. In fact, the Turbo 182 has
one that isn't: a (carbureted) Lyc 0-540.

[Michael 182]

Really - my carbureted 182 calls for full rich on takeoff

"Mark Mallory" > wrote in message
...

>
> 'Generally speaking', but not necessarily. Full-rich is the correct
takeoff
> setting for a FUEL-INJECTED engine regardless of altitude, but *not* for a
> CARBURETED engine.
>
> Most turbocharged engines are injected, but not all. In fact, the Turbo
182 has
> one that isn't: a (carbureted) Lyc 0-540.
>

[Mark Mallory]

Michael 182 wrote:
> Really - my carbureted 182 calls for full rich on takeoff

So does mine - at SL on a standard day.

But not on a hot 95 degF afternoon at 5000 MSL.

[john smith]

Peter Duniho wrote:
>
> "john smith" > wrote in message
> ...
> > [...] Had you need to do a go
> > around, the cruise mixture would have been sufficient for a full power
> > go-around.
>
> You do understand that he's talking about a turbocharged engine, right?
> Generally speaking, full rich is the correct mixture setting for a
> turbocharged piston engine, for full-power takeoffs regardless of altitude.


Yes, I remembered the turbo part this afternoon.
For descent there is no reason to change the mixture unless you are
going to push the throttle back in beyond the cruise power setting.
For takeoff, the turbo should maintain sealevel power up to 12,000 feet
MSL, so full rich or slightly leaned mixture would be used on takeoff. I
think I would still lean for best power prior to releasing brakes for
takeoff.

[Rick Durden]

Michael,

What do you experience that causes you to have to enrichen your
mixture as you descend on your airplane? Are you descending while
carrying a very high power setting? I'm asking because I've flown
T182s and TR182s and have never run into a situation that required
enrichening the mixture during descent unless I leveled off at some
intermediate altitude and went to a relatively high power setting.

Otherwise, the only reason to enrichen the mixture during descent is
if the engine actually begins to run roughly. (See the POH which only
recommends enrichening if you experience engine roughness.) Most
people descend at 65% power or less, which means that it is impossible
to detonate the engine due to lack of heat and pressure, so it's
impossible to run it too lean (it will simply start to run rough and
then quit if you get it too lean, you won't hurt anything). Keeping
it leaned during descent helps avoid overcooling (if you believe in
shock cooling), helps keep the plugs from fouling and doesn't waste
fuel. In general, once you lean the engine for cruise on a T182 you
needn't touch the mixture control until you pull it to idle cutoff
after landing, or to go to full rich on a go around.

All the best,
Rick

"Michael 182" > wrote in message news:<KXjMb.26563$5V2.40699@attbi_s53>...
> Are you sure about this? I always have to enrichen the mixture as I decrease
> altitude.
>
> Michael
>
>
> "john smith" > wrote in message
> ...
> > Barry Klein wrote:
> > >
> > > How should we have found the correct mixture setting
> > > for power-off final approach, when the turbo is basically adding no
> > > boost and we are at high density altitude?
> >
> > Did you enrichen the mixture between cruise and landing?
> > There should have been no reason to. As you reduce altitude and MP, the
> > mixture will enrichen with decrease in altitude. Had you need to do a go
> > around, the cruise mixture would have been sufficient for a full power
> > go-around.

[David Rind]

Rick Durden wrote:
> Otherwise, the only reason to enrichen the mixture during descent is
> if the engine actually begins to run roughly. (See the POH which only
> recommends enrichening if you experience engine roughness.) Most
> people descend at 65% power or less, which means that it is impossible
> to detonate the engine due to lack of heat and pressure, so it's
> impossible to run it too lean (it will simply start to run rough and
> then quit if you get it too lean, you won't hurt anything). Keeping
> it leaned during descent helps avoid overcooling (if you believe in
> shock cooling), helps keep the plugs from fouling and doesn't waste
> fuel. In general, once you lean the engine for cruise on a T182 you
> needn't touch the mixture control until you pull it to idle cutoff
> after landing, or to go to full rich on a go around.
>
> All the best,
> Rick

The POH for my TB-21 (turbocharged Trinidad) with a
Lycoming TIO-540 calls for putting the mixture full rich
prior to landing. Is that different from what most people
do with this engine?

--
David Rind

[Michael 182]

I'll check my POH - I tend to enrichen somewhat by the fuel flow on the
Shadin - maybe this is a bad habit. I'm sure I'm not over 65% on the
descent.

Michael

"Rick Durden" > wrote in message
m...
> Michael,
>
> What do you experience that causes you to have to enrichen your
> mixture as you descend on your airplane? Are you descending while
> carrying a very high power setting? I'm asking because I've flown
> T182s and TR182s and have never run into a situation that required
> enrichening the mixture during descent unless I leveled off at some
> intermediate altitude and went to a relatively high power setting.
>
> Otherwise, the only reason to enrichen the mixture during descent is
> if the engine actually begins to run roughly. (See the POH which only
> recommends enrichening if you experience engine roughness.)

[[email protected]]

Yes. The mixture was too rich.
This is a common problem with big-bore engines when operated
above 3000 MSL.

What we teach at Colorado Pilots Association is to set the
mixture to 15 GPH as you enter the pattern at (near) cruise
power. That way the engine continues to run on the ground. :-)

Of course, if you do a balked landing, you MUST push the mixture
full in after you increase the power for the go around.

Barry Klein > wrote:
> We took a newer 182 turbo to a 7000' elevation airport yesterday and
> the engine quit at the end of the landing roll. I'm sure the mixture
> was way too rich. It restarted without incident, glad we were on the
> ground! We had the mixture set about 100 deg rich of peak TIT for
> cruise at 9500. How should we have found the correct mixture setting
> for power-off final approach, when the turbo is basically adding no
> boost and we are at high density altitude? This is not addressed in
> the POH. It does say full rich on takoff regardless of airport
> elevation. Later that day, when taxiing for takoff, we set 1200 rpm
> and leaned for peak rpm, mixture knob was out 1.5-2 inches to achieve
> this.

> When we returned home to 800' elevation, we checked the idle speed at
> full rich, it was about 500 rpm, is this too low?


> Thanks,
> Barry


Best regards,

Jer/ "Flight instruction and mountain flying are my vocation!" Eberhard

--
Jer/ (Slash) Eberhard, Mountain Flying Aviation, LTD, Ft Collins, CO
CELL 970 231-6325 EMAIL jer'at'frii.com WEB http://www.frii.net/~jer
C-206 N9513G, CFII Airplane&Glider, FAA-DEN Aviation Safety Counselor
CAP-CO Mission&Aircraft CheckPilot, BM218 HAM N0FZD, 197 Young Eagles!

[Peter Duniho]

"David Rind" > wrote in message
...
> The POH for my TB-21 (turbocharged Trinidad) with a
> Lycoming TIO-540 calls for putting the mixture full rich
> prior to landing. Is that different from what most people
> do with this engine?

What actual model engine does the TB-21 have? Just knowing that it's a
TIO-540 doesn't give us enough information to compare with our own engines.

The engine in my plane, a TIO-540-AA1AD, cannot stay running at full rich at
idle at high density altitudes, as I mentioned in another post. I put the
mixture to full rich before landing only when landing below 3000' or so (and
then only so that I am more prepared for a go-around...operationally, I wind
up leaning again after leaving the runway so that the plugs don't foul).

Pete

[Peter Duniho]

"Mark Mallory" > wrote in message
...
>
> Michael 182 wrote:
> > Really - my carbureted 182 calls for full rich on takeoff
>
> So does mine - at SL on a standard day.
>
> But not on a hot 95 degF afternoon at 5000 MSL.

What's the critical altitude of the turbocharged engine in your airplane?
Is it above or below the density altitude for that 95 F at 5000'?

As long as you are taking off at full power, I see no reason why you would
not use full rich mixture. Conversely, if even with the turbocharger, you
cannot make full power, I can believe one would need to lean.

I don't see why the difference should be between fuel-injected versus
carbureted. The metering is basically the same for both; only the method of
delivery is different.

Pete

[Peter Duniho]

"john smith" > wrote in message
...
> [...]
> For takeoff, the turbo should maintain sealevel power up to 12,000 feet
> MSL, so full rich or slightly leaned mixture would be used on takeoff. I
> think I would still lean for best power prior to releasing brakes for
> takeoff.

You need to use full rich to keep the exhaust temperature down. With the
turbocharged engine I normally fly, in my airplane, about a third of the
fuel is used just for cooling (30 gph at full power, when theoretically only
about 20 gph would be needed for the 270 hp). The turbocharger controller
ensures that I am getting best power, without any fiddling with the mixture
at all. Even in an aircraft with a manual wastegate, one would ensure best
power using that control, not the mixture.

Pete

[Peter Duniho]

"Jeff" > wrote in message
...
> is this a turbo charged engine also?

Is what a turbocharged engine also? Both the engine that John Smith is
talking about and the engine that I am talking about are turbocharged, as we
both stated in our posts.

> I have taken off with a DA of 8800 ft, full rich and not had a problem in
my
> T-arrow I use full rich on take off and landing, as my POH says to do.

Have you landed with a DA of 8800' with the mixture full rich? On my
airplane (and apparently John's), the engine would stop on rollout. That
said, maybe you have a superior fuel system on the Turbo Arrow, or perhaps
the engine is just somehow inherently more immune to overly rich mixtures.

Pete

[EDR]

In article >, Barry
Klein > wrote:

> How should we have found the correct mixture setting
> for power-off final approach, when the turbo is basically adding no
> boost and we are at high density altitude?

My best advice is to go to www.avweb.com and read all of John Deakin's
articles on engine operation. These are gems of wisdom that every
flight instructor should have in their kit.

Somewhere I read an article that related that many aircraft
carburetors/injectors are not properly set for idle.

[Dennis O'Connor]

How does it idle? 500 rpm is the bottom end... Another 25 - 30 rpm may help
if it is idling rough...

On the issue of full rich, if you are landing at a low altitude airport then
progressivley enriching the mixture in the descent,arriving at full rich on
short final, makes sense, as the air density in the manifold will be
reasonably high, even after the turbo has spun down and is not boosting
much...
But, if you are landing at an altitude airport, then the throttle pulled
back will allow the turbo to spin down, same as for low altitude airports,
but the intake manifold air density will be low <thin> and full rich may
lead to a flame out - especially if you have to hit the throttle for a
missed approach, wind shear, etc... Full rich with full throttle is likely
to cause a stumble/stall at that point.... I would tend to keep it
reasonably lean during descent and approach to avoid plug fouling and to
keep it warm, only going to the 'appropriate' takeoff setting on short
final, which is not necessarily full rich at higher altitude airports...
You have already done your homework and know how far in to put the mixture
on short final for the airport you were at... For takeoff, I would run up
to 1800 rpm and lean for best power, knowing that full throttle will enrich
the mixture further, automatically... Just watch your manifold pressure and
cylinder head temps during climbout and richen slightly if needed...
denny

"Barry Klein" > wrote in message
om...
> We took a newer 182 turbo to a 7000' elevation airport yesterday and
> the engine quit at the end of the landing roll. I'm sure the mixture
> was way too rich.

[John Harper]

FWIW here's my TR182 experience. Of course the engine in
a TR182 is a very different beast from a T182T (carburetted
rather than injected, and turbo-normalized only, never boost above
31").

Full rich for takeoff, regardless of altitude, at 31" MP.
Lean to around 18 GPH (1350 or so TIT) with power reduction
to 25" at around 1000 AGL.

Lean to 1450 TIT for cruise.

Descend without further adjustment - TIT remains steady.
I've never experienced rough running in this situation.

Full rich as part of GUMPS check prior to takeoff, in
case of go-around.

John

"Barry Klein" > wrote in message
om...
> We took a newer 182 turbo to a 7000' elevation airport yesterday and
> the engine quit at the end of the landing roll. I'm sure the mixture
> was way too rich. It restarted without incident, glad we were on the
> ground! We had the mixture set about 100 deg rich of peak TIT for
> cruise at 9500. How should we have found the correct mixture setting
> for power-off final approach, when the turbo is basically adding no
> boost and we are at high density altitude? This is not addressed in
> the POH. It does say full rich on takoff regardless of airport
> elevation. Later that day, when taxiing for takoff, we set 1200 rpm
> and leaned for peak rpm, mixture knob was out 1.5-2 inches to achieve
> this.
>
> When we returned home to 800' elevation, we checked the idle speed at
> full rich, it was about 500 rpm, is this too low?
>
>
> Thanks,
> Barry

[Rick Durden]

David,

I believe your POH does call for full rich prior to landing (but not
in the descent) in preparation for a possible go around. Otherwise,
there is no reason to enrichen it.

At very high altitude airports, landing with full rich mixture may
cause a rough idle or the engine may actually quit at the end of
rollout, but that depends on the idle mixture adjustment on your
engine.

If your engine runs fine at full rich at low power settings on the
ground, then there is no problem with going to full rich on final in
preparation for a go around. However, you may want to lean it while
taxiing (lean it a long ways so that it will simply quit should you
try to take off prior to going to full rich and it will remind you) so
as to help avoid plug fouling.

All the best,
Rick

David Rind > wrote in message >...
> Rick Durden wrote:
> > Otherwise, the only reason to enrichen the mixture during descent is
> > if the engine actually begins to run roughly. (See the POH which only
> > recommends enrichening if you experience engine roughness.) Most
> > people descend at 65% power or less, which means that it is impossible
> > to detonate the engine due to lack of heat and pressure, so it's
> > impossible to run it too lean (it will simply start to run rough and
> > then quit if you get it too lean, you won't hurt anything). Keeping
> > it leaned during descent helps avoid overcooling (if you believe in
> > shock cooling), helps keep the plugs from fouling and doesn't waste
> > fuel. In general, once you lean the engine for cruise on a T182 you
> > needn't touch the mixture control until you pull it to idle cutoff
> > after landing, or to go to full rich on a go around.
> >
> > All the best,
> > Rick
>
> The POH for my TB-21 (turbocharged Trinidad) with a
> Lycoming TIO-540 calls for putting the mixture full rich
> prior to landing. Is that different from what most people
> do with this engine?

[Jeff]

yes that was the question, I did not see where you said yours was a turbo
charged also, must have over looked it.

yes I have landed to refuel with the DA at 8800 ft.

Is it superior - beats me, I just follow my POH and havnt had a problem yet.

Peter Duniho wrote:

>
>
> Is what a turbocharged engine also? Both the engine that John Smith is
> talking about and the engine that I am talking about are turbocharged, as we
> both stated in our posts.
>
> > I have taken off with a DA of 8800 ft, full rich and not had a problem in
> my
> > T-arrow I use full rich on take off and landing, as my POH says to do.
>
> Have you landed with a DA of 8800' with the mixture full rich? On my
> airplane (and apparently John's), the engine would stop on rollout. That
> said, maybe you have a superior fuel system on the Turbo Arrow, or perhaps
> the engine is just somehow inherently more immune to overly rich mixtures.
>
> Pete

[Jeff]

maybe a stupid question, but if its going to quit on you when you go full
rich on landing, then dont it also risk the chance of quitting if you go
full rich on a go around?
unless its just the high power that keeps it running and idle is what
kills it.

wrote:

> Yes. The mixture was too rich.
> This is a common problem with big-bore engines when operated
> above 3000 MSL.
>
> What we teach at Colorado Pilots Association is to set the
> mixture to 15 GPH as you enter the pattern at (near) cruise
> power. That way the engine continues to run on the ground. :-)
>
> Of course, if you do a balked landing, you MUST push the mixture
> full in after you increase the power for the go around.
>
> Barry Klein > wrote:
> > We took a newer 182 turbo to a 7000' elevation airport yesterday and
> > the engine quit at the end of the landing roll. I'm sure the mixture
> > was way too rich. It restarted without incident, glad we were on the
> > ground! We had the mixture set about 100 deg rich of peak TIT for
> > cruise at 9500. How should we have found the correct mixture setting
> > for power-off final approach, when the turbo is basically adding no
> > boost and we are at high density altitude? This is not addressed in
> > the POH. It does say full rich on takoff regardless of airport
> > elevation. Later that day, when taxiing for takoff, we set 1200 rpm
> > and leaned for peak rpm, mixture knob was out 1.5-2 inches to achieve
> > this.
>
> > When we returned home to 800' elevation, we checked the idle speed at
> > full rich, it was about 500 rpm, is this too low?
>
> > Thanks,
> > Barry
>
> Best regards,
>
> Jer/ "Flight instruction and mountain flying are my vocation!" Eberhard
>
> --
> Jer/ (Slash) Eberhard, Mountain Flying Aviation, LTD, Ft Collins, CO
> CELL 970 231-6325 EMAIL jer'at'frii.com WEB http://www.frii.net/~jer
> C-206 N9513G, CFII Airplane&Glider, FAA-DEN Aviation Safety Counselor
> CAP-CO Mission&Aircraft CheckPilot, BM218 HAM N0FZD, 197 Young Eagles!

[EDR]

In article >, Jeff
> wrote:

> maybe a stupid question, but if its going to quit on you when you go full
> rich on landing, then dont it also risk the chance of quitting if you go
> full rich on a go around?
> unless its just the high power that keeps it running and idle is what
> kills it.

Go around on approach (depending on height AGL), you will still have
some air under you and it is amazing how fast your hand will push that
mixture lever forward.

[David Rind]

Rick Durden wrote:
> David,
>
> I believe your POH does call for full rich prior to landing (but not
> in the descent) in preparation for a possible go around. Otherwise,
> there is no reason to enrichen it.
>
> At very high altitude airports, landing with full rich mixture may
> cause a rough idle or the engine may actually quit at the end of
> rollout, but that depends on the idle mixture adjustment on your
> engine.
>
> If your engine runs fine at full rich at low power settings on the
> ground, then there is no problem with going to full rich on final in
> preparation for a go around. However, you may want to lean it while
> taxiing (lean it a long ways so that it will simply quit should you
> try to take off prior to going to full rich and it will remind you) so
> as to help avoid plug fouling.
>
> All the best,
> Rick

Thanks! So then if I think I'm capable of remembering to push
in the mixture on a go around there is really no need to enrich
the mixture prior to landing. FWIW, I'm good about aggressively
leaning once I'm off the runway.

--
David Rind

[David Rind]

Peter Duniho wrote:
> What actual model engine does the TB-21 have? Just knowing that it's a
> TIO-540 doesn't give us enough information to compare with our own engines.

TIO-540-AB1AD

--
David Rind

[[email protected]]

Jeff > wrote:
> maybe a stupid question, but if its going to quit on you when you go full
> rich on landing, then dont it also risk the chance of quitting if you go
> full rich on a go around?
> unless its just the high power that keeps it running and idle is what
> kills it.

Your guesstimation is correct! The higher power can deal with the
enrichened mixture, and your balked landing (go around) will succeed.

Notice that I said below to increase the power, then the mixture:

>> Of course, if you do a balked landing, you MUST push the mixture
>> full in after you increase the power for the go around.

Best regards,

Jer/

> wrote:

>> Yes. The mixture was too rich.
>> This is a common problem with big-bore engines when operated
>> above 3000 MSL.

>> What we teach at Colorado Pilots Association is to set the
>> mixture to 15 GPH as you enter the pattern at (near) cruise
>> power. That way the engine continues to run on the ground. :-)

>> Of course, if you do a balked landing, you MUST push the mixture
>> full in after you increase the power for the go around.

>> Barry Klein > wrote:
>> > We took a newer 182 turbo to a 7000' elevation airport yesterday and
>> > the engine quit at the end of the landing roll. I'm sure the mixture
>> > was way too rich. It restarted without incident, glad we were on the
>> > ground! We had the mixture set about 100 deg rich of peak TIT for
>> > cruise at 9500. How should we have found the correct mixture setting
>> > for power-off final approach, when the turbo is basically adding no
>> > boost and we are at high density altitude? This is not addressed in
>> > the POH. It does say full rich on takeoff regardless of airport
>> > elevation. Later that day, when taxiing for takeoff, we set 1200 rpm
>> > and leaned for peak rpm, mixture knob was out 1.5-2 inches to achieve
>> > this.

>> > When we returned home to 800' elevation, we checked the idle speed at
>> > full rich, it was about 500 rpm, is this too low?

>> > Thanks,
>> > Barry

Best regards,

Jer/ "Flight instruction and mountain flying are my vocation!" Eberhard

--
Jer/ (Slash) Eberhard, Mountain Flying Aviation, LTD, Ft Collins, CO
CELL 970 231-6325 EMAIL jer'at'frii.com WEB http://www.frii.net/~jer
C-206 N9513G, CFII Airplane&Glider, FAA-DEN Aviation Safety Counselor
CAP-CO Mission&Aircraft CheckPilot, BM218 HAM N0FZD, 197 Young Eagles!

[Jeff]

you would think that since its a turbo airplane, cessna would expect it to be
used at high altitude airports so they would have made it so it would not cut
out on landing.

wrote:

> Jeff > wrote:
> > maybe a stupid question, but if its going to quit on you when you go full
> > rich on landing, then dont it also risk the chance of quitting if you go
> > full rich on a go around?
> > unless its just the high power that keeps it running and idle is what
> > kills it.
>
> Your guesstimation is correct! The higher power can deal with the
> enrichened mixture, and your balked landing (go around) will succeed.
>
> Notice that I said below to increase the power, then the mixture:
>
> >> Of course, if you do a balked landing, you MUST push the mixture
> >> full in after you increase the power for the go around.
>
> Best regards,
>
> Jer/
>
> > wrote:
>
> >> Yes. The mixture was too rich.
> >> This is a common problem with big-bore engines when operated
> >> above 3000 MSL.
>
> >> What we teach at Colorado Pilots Association is to set the
> >> mixture to 15 GPH as you enter the pattern at (near) cruise
> >> power. That way the engine continues to run on the ground. :-)
>
> >> Of course, if you do a balked landing, you MUST push the mixture
> >> full in after you increase the power for the go around.
>
> >> Barry Klein > wrote:
> >> > We took a newer 182 turbo to a 7000' elevation airport yesterday and
> >> > the engine quit at the end of the landing roll. I'm sure the mixture
> >> > was way too rich. It restarted without incident, glad we were on the
> >> > ground! We had the mixture set about 100 deg rich of peak TIT for
> >> > cruise at 9500. How should we have found the correct mixture setting
> >> > for power-off final approach, when the turbo is basically adding no
> >> > boost and we are at high density altitude? This is not addressed in
> >> > the POH. It does say full rich on takeoff regardless of airport
> >> > elevation. Later that day, when taxiing for takeoff, we set 1200 rpm
> >> > and leaned for peak rpm, mixture knob was out 1.5-2 inches to achieve
> >> > this.
>
> >> > When we returned home to 800' elevation, we checked the idle speed at
> >> > full rich, it was about 500 rpm, is this too low?
>
> >> > Thanks,
> >> > Barry
>
> Best regards,
>
> Jer/ "Flight instruction and mountain flying are my vocation!" Eberhard
>
> --
> Jer/ (Slash) Eberhard, Mountain Flying Aviation, LTD, Ft Collins, CO
> CELL 970 231-6325 EMAIL jer'at'frii.com WEB http://www.frii.net/~jer
> C-206 N9513G, CFII Airplane&Glider, FAA-DEN Aviation Safety Counselor
> CAP-CO Mission&Aircraft CheckPilot, BM218 HAM N0FZD, 197 Young Eagles!

[Jeff]

Hey do the cessna turbo's come standard with a intercooler and automatic
wastegate or do you have to get an after market one (if you decide to get
it at all)


John Harper wrote:

> FWIW here's my TR182 experience. Of course the engine in
> a TR182 is a very different beast from a T182T (carburetted
> rather than injected, and turbo-normalized only, never boost above
> 31").
>
> Full rich for takeoff, regardless of altitude, at 31" MP.
> Lean to around 18 GPH (1350 or so TIT) with power reduction
> to 25" at around 1000 AGL.
>
> Lean to 1450 TIT for cruise.
>
> Descend without further adjustment - TIT remains steady.
> I've never experienced rough running in this situation.
>
> Full rich as part of GUMPS check prior to takeoff, in
> case of go-around.
>
> John
>
> "Barry Klein" > wrote in message
> om...
> > We took a newer 182 turbo to a 7000' elevation airport yesterday and
> > the engine quit at the end of the landing roll. I'm sure the mixture
> > was way too rich. It restarted without incident, glad we were on the
> > ground! We had the mixture set about 100 deg rich of peak TIT for
> > cruise at 9500. How should we have found the correct mixture setting
> > for power-off final approach, when the turbo is basically adding no
> > boost and we are at high density altitude? This is not addressed in
> > the POH. It does say full rich on takoff regardless of airport
> > elevation. Later that day, when taxiing for takoff, we set 1200 rpm
> > and leaned for peak rpm, mixture knob was out 1.5-2 inches to achieve
> > this.
> >
> > When we returned home to 800' elevation, we checked the idle speed at
> > full rich, it was about 500 rpm, is this too low?
> >
> >
> > Thanks,
> > Barry

[Peter Duniho]

"Jeff" > wrote in message
...
> you would think that since its a turbo airplane, cessna would expect it to
be
> used at high altitude airports so they would have made it so it would not
cut
> out on landing.

And yet, this is a common enough issue, with many different makes and models
of turbocharged aircraft.

Why single Cessna out? There's all sorts of inconveniences related to the
technologies used in "modern" aircraft. One of them happens to be the
likelihood of engine stoppage if the mixture is set to full-rich at high
density altitudes. This isn't unique to Cessna, and it seems to me it's
along the lines of "Doc, it hurts when I do this..." joke. Since it "hurts"
when one does that, one just doesn't do that.

Simple enough, IMHO. The main problem is that, for some reason, pilots who
are introduced to turbocharged aircraft are often not told about the need to
avoid full-rich mixture settings at high density altitudes. This was true
of me (I found out myself the hard way...only took two high altitude
landings for me to figure it out though :) ), and it's apparently true of
other pilots as well.

Pete

[EDR]

In article >, Peter Duniho
> wrote:

> Simple enough, IMHO. The main problem is that, for some reason, pilots who
> are introduced to turbocharged aircraft are often not told about the need to
> avoid full-rich mixture settings at high density altitudes. This was true
> of me (I found out myself the hard way...only took two high altitude
> landings for me to figure it out though :) ), and it's apparently true of
> other pilots as well.

The real problem is, most pilots are flat-landers.
There just is not the opportunity to train pilots in the real world
environment until they actually get there.

[John Galban]

"Peter Duniho" > wrote in message >...
> The main problem is that, for some reason, pilots who
> are introduced to turbocharged aircraft are often not told about the need to
> avoid full-rich mixture settings at high density altitudes. This was true
> of me (I found out myself the hard way...only took two high altitude
> landings for me to figure it out though :) ), and it's apparently true of
> other pilots as well.
>

This is not isolated to pilots of turbocharged aircraft. Every
summer I see flatland pilots in the high country blindly following a
"mixture - rich" item on a landing checklist and killing the engine on
rollout. A go-around attempt will usually result in a belch of black
smoke and a close encounter with pine trees if they're lucky, bent
metal if they're not.

John Galban=====>N4BQ (PA28-180)

[Jeff]

I am glad this isnt an issue with the turbo arrows.



>
>
> Simple enough, IMHO. The main problem is that, for some reason, pilots who
> are introduced to turbocharged aircraft are often not told about the need to
> avoid full-rich mixture settings at high density altitudes. This was true
> of me (I found out myself the hard way...only took two high altitude
> landings for me to figure it out though :) ), and it's apparently true of
> other pilots as well.
>
> Pete

[Peter Duniho]

"EDR" > wrote in message
...
> The real problem is, most pilots are flat-landers.
> There just is not the opportunity to train pilots in the real world
> environment until they actually get there.

One need not witness the engine stopping to learn to not land with the
mixture full rich at high density altitudes. If I had been taught, when I
got checked out in my first turbocharged airplane, to not land with mixture
full rich at high density altitudes, I'm sure it would have only taken ONE
engine stoppage for me to figure out what was wrong. I might have avoided
it altogether.

My point is that it doesn't sound like anyone is even bothering to mention
this. It's not just a matter of poor retention due to lack of first-hand
experience.

Pete