Engine failure

[Jase Vanover]

I had a situation yesterday at the end of my local "just because" flight
(you know, one of those where you really have no place to go but the weather
is favourable and you just want to go flying).

Was flying a rental 172. Took off like a rocket (lightly loaded solo...
cold air about freezing), tooled around practicing stalls, steep turns, etc.
Headed back to the pattern and did a couple of touch and goes. On my final
landing, I declared a full stop, and decided I would practice a short field
landing. I cleared the "imaginary" 50 ft. obstacle, dropped the last notch
of flaps and cut power... and the engine quit. No issues, because I had the
runway made (I didn't even realize that the engine had quit until rolling on
the runway... I knew something sounded different, but the prop was still
windmilling and I was concentrating on the flare).

I rolled out and the prop stopped, and I called traffic (uncontrolled
airport) to let them know I was a sitting duck. Checked the primer
(locked), mixture (full rich), fuel selector (both... and lots of fuel... I
filled up with only just over an hour of flight since), and restarted with
no problems and taxied off the runway.

Though it turned out to be no danger, I couldn't help but feel a little
disconcerted. A low level power off descent away from the airport could
have had a more serious outcome, or what if I misjudged and didn't have the
runway made when I cut power?

I taxied to the maintenance hanger (after being directed there by the FBO
via radio notification of the situation), and explained what happened to the
maintenance guy. He said that there is a stop on the throttle to keep the
idle setting from being too low that probably needed adjustment. Even so,
during shutdown (after restarting), idle setting on the throttle was still
800 - 900 RPM, which should be enough to keep the engine running I would
think.

Anyone else experienced this and can share their thoughts? I'm about a 60
hour pilot, so not much experience.

[Longworth]

Jase,
Do you remember putting the carb heat when cutting power? It sounded
like carb ice problem to me.

Hai Longworth

[Matt Whiting]

Jase Vanover wrote:

> I had a situation yesterday at the end of my local "just because" flight
> (you know, one of those where you really have no place to go but the weather
> is favourable and you just want to go flying).
>
> Was flying a rental 172. Took off like a rocket (lightly loaded solo...
> cold air about freezing), tooled around practicing stalls, steep turns, etc.
> Headed back to the pattern and did a couple of touch and goes. On my final
> landing, I declared a full stop, and decided I would practice a short field
> landing. I cleared the "imaginary" 50 ft. obstacle, dropped the last notch
> of flaps and cut power... and the engine quit. No issues, because I had the
> runway made (I didn't even realize that the engine had quit until rolling on
> the runway... I knew something sounded different, but the prop was still
> windmilling and I was concentrating on the flare).
>
> I rolled out and the prop stopped, and I called traffic (uncontrolled
> airport) to let them know I was a sitting duck. Checked the primer
> (locked), mixture (full rich), fuel selector (both... and lots of fuel... I
> filled up with only just over an hour of flight since), and restarted with
> no problems and taxied off the runway.
>
> Though it turned out to be no danger, I couldn't help but feel a little
> disconcerted. A low level power off descent away from the airport could
> have had a more serious outcome, or what if I misjudged and didn't have the
> runway made when I cut power?
>
> I taxied to the maintenance hanger (after being directed there by the FBO
> via radio notification of the situation), and explained what happened to the
> maintenance guy. He said that there is a stop on the throttle to keep the
> idle setting from being too low that probably needed adjustment. Even so,
> during shutdown (after restarting), idle setting on the throttle was still
> 800 - 900 RPM, which should be enough to keep the engine running I would
> think.
>
> Anyone else experienced this and can share their thoughts? I'm about a 60
> hour pilot, so not much experience.

I don't see any mention of carb heat being applied during your descent.
Cessna's are rather prone to carb icing and carb heat has been on the
descent and landing checklist of every Cessna model I've flown (150, 172
and 182). If you didn't have carb heat applied, then I'd suspect carb
icing.

The other thing many training guides (atleast the older ones that I own)
recommend is to "clear the engine" periodically duing long descents to
prevent the engine from "loading up and stalling." I'll admit to never
having developed this practice and never having had a problem with an
engine stalling during a long descent, however, I suspect it is possible
otherwise these warnings would be completely baseless.


Matt

[tony roberts]

> It sounded
> like carb ice problem to me.

Doesn't sound like carb ice to me.

Tony
--

Tony Roberts
PP-ASEL
VFR OTT
Night
Cessna 172H C-GICE

[George Patterson]

Longworth wrote:

> It sounded like carb ice problem to me.

If it were carb ice, the engine would not have restarted easily.

George Patterson
Drink is the curse of the land. It makes you quarrel with your neighbor.
It makes you shoot at your landlord. And it makes you miss him.

[Longworth]

George,
The restart did not happen right after the engine had quit but on
the ground after landing. It is possible the ice melted in the interval
thus allowed 'normal' start.

If you don't think it was carb ice, what would be other potential
causes?

Hai Longworth

[Jose]

I had a situation in the Shenandoah Valley where, during runup when I
checked smooth operation at idle, the engine quit. It started up easily
enough, but quit again at idle. Taxiied back, went to the shop and they
poked around with the plugs and a few other things, finding nothing.
Their theory was that it was carb ice.

Never had carb ice on the ground before.

Several hours later I took off with no problem (during taxi and runup I
applied carb heat periodically).

Plane was a Dakota.

Jose
--
Money: what you need when you run out of brains.
for Email, make the obvious change in the address.

[Dale]

In article . com>,
"Longworth" > wrote:

> George,
> The restart did not happen right after the engine had quit but on
> the ground after landing. It is possible the ice melted in the interval
> thus allowed 'normal' start.
>
> If you don't think it was carb ice, what would be other potential
> causes?


Not uncommon for an engine to quit after a long idle descent on final.
As another poster mentioned, it used to be taught to "clear" the engine
occasionaly. Keeps the temps up a little and I guess reduces the chance
of it "loading up" and quiting.

If this was a Lycoming powered 172 carb ice is not as likely as with a
Continental engine.

--
Dale L. Falk

There is nothing - absolutely nothing - half so much worth doing
as simply messing around with airplanes.

http://home.gci.net/~sncdfalk/flying.html

[Bob Gardner]

I've experienced ice with Continentals on the ground in the lovely warm
months of July and August. Finally learned to pull the carb heat one last
time just as I rolled into position and to get rid of it as I added takeoff
power. It ain't the heat, it's the humidity.

Bob Gardner

"Jose" > wrote in message
. ..
>I had a situation in the Shenandoah Valley where, during runup when I
>checked smooth operation at idle, the engine quit. It started up easily
>enough, but quit again at idle. Taxiied back, went to the shop and they
>poked around with the plugs and a few other things, finding nothing. Their
>theory was that it was carb ice.
>
> Never had carb ice on the ground before.
>
> Several hours later I took off with no problem (during taxi and runup I
> applied carb heat periodically).
>
> Plane was a Dakota.
>
> Jose
> --
> Money: what you need when you run out of brains.
> for Email, make the obvious change in the address.

[Rob]

Jase Vanover wrote:
> I taxied to the maintenance hanger (after being directed there by the FBO
> via radio notification of the situation), and explained what happened to the
> maintenance guy. He said that there is a stop on the throttle to keep the
> idle setting from being too low that probably needed adjustment. Even so,
> during shutdown (after restarting), idle setting on the throttle was still
> 800 - 900 RPM, which should be enough to keep the engine running I would
> think.

Did you have the carb heat on when the engine died in the air and off
when you couldn't make the engine fail on the ground? Maybe the idle
setting was low enough that the additional RPM loss due to the carb
heat made a difference.

-R

[Jay Honeck]

> Their theory was that it was carb ice.
>
> Plane was a Dakota.

Interesting. If so, that's the first instance of carb icing I've heard
about with a Dakota.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

[George Patterson]

Jay Honeck wrote:

> Interesting. If so, that's the first instance of carb icing I've heard
> about with a Dakota.

Lycomings rarely suffer from carb icing because the air intake is routed through
the oil sump on most models. This keeps the carb warm.

Unless, of course, you just started the engine a few minutes ago and the oil's
still cold.

As of two years ago, Shenandoah Valley impressed me as having a pretty competent
shop.

George Patterson
Drink is the curse of the land. It makes you quarrel with your neighbor.
It makes you shoot at your landlord. And it makes you miss him.

[Happy Dog]

"Jase Vanover" >

> I taxied to the maintenance hanger (after being directed there by the FBO
> via radio notification of the situation), and explained what happened to
> the maintenance guy. He said that there is a stop on the throttle to keep
> the idle setting from being too low that probably needed adjustment. Even
> so, during shutdown (after restarting), idle setting on the throttle was
> still 800 - 900 RPM, which should be enough to keep the engine running I
> would think.
>
> Anyone else experienced this and can share their thoughts? I'm about a 60
> hour pilot, so not much experience.

Part of the run-up is a slow idle check. You should pull the throttle
fairly hard to see if the idle speed falls significantly below the spec'd
minimum. I don't know if that's what happened to you, but it's pretty
common.

I was flying into La Guardia on Air Canada and I saw a Bonanza rolling out
with the engine stopped. By total coincidence, exiting the plane, I got a
call from that pilot's instructor who'd briefed the pilot on this X/C. He
said that there was a known problem with that plane and, I think, said that
it was not an uncommon problem with that type of plane. Odd thing,
coincidence.

Anyway, engines quitting on final is an occasional story topic. There you
go...

moo

[cjcampbell]

I think your mechanic was right. RPM has nothing to do with whether the
engine is getting gas. It will windmill at 800-900 RPM with the engine
off. I have seen this problem before. It is not extremely rare. An idle
check on runup should discover it, unless you finally managed to loosen
the throttle just enough on short final for it to finally stop working.

The reason I do not think it was carb ice is that the weather was below
freezing, which means that the air was probably relatively dry and it
may even have been too cold for carb ice to form (the air would have to
have liquid water precipitate out of it to cause carb ice, meaning that
the air would have to be warmed in the carburetor, not cooled, and
somehow also exceed 100% humidity in the process).

This is one reason many instructors are so dead set against their
students getting low on final. You can run out of options real fast,
and a disproportionate number of engine failures happen there.

Engines almost always fail just when you change something: throttle,
carb heat, mixture, prop, etc. There can be a lot wrong with an engine
and it will keep running if you never change anything, but a
configuration change will often be the last straw before she quits.
Before making any adjustments to an engine it is good practice to scan
the area for emergency landing fields.

[Happy Dog]

"cjcampbell" > wrote in message news:

> This is one reason many instructors are so dead set against their
> students getting low on final. You can run out of options real fast,
> and a disproportionate number of engine failures happen there.

Evidence?

>
> Engines almost always fail just when you change something: throttle,
> carb heat, mixture, prop, etc. There can be a lot wrong with an engine
> and it will keep running if you never change anything, but a
> configuration change will often be the last straw before she quits.
> Before making any adjustments to an engine it is good practice to scan
> the area for emergency landing fields.

Power changes are taught as SOP for climbs and descents. If what you say is
true (and I don't know it isn't, but I doubt it) engine outs could be
reduced by climbing or descending without power changes. Or at least
deferred until landing.

moo

[Denny]

Carb ice, period!

If it was a fuel pump, mag, loose throttle stop, stuck lifters, etc.,
none of these things cure themselves after the engine stops. An iced
up air filter might melt off, but not in seconds... Carb ice is the one
thing that will clear within seconds inside of a warm engine once the
windmilling stops, which stops it pulling more cold air across the
venturi... . And a Lycoming will ice up... I had an engine on Fat
Albert go limp at 11,500 feet over top of the Detroit B on a winter
day, and it was 25 degrees at our altitude...
A few years back I lost an old high school classmate from Caro,
Michigan when he went for a student night flight in a Cherokee, iced up
and then stalled it before he got to the ground...

Claiming it couldn't be carb ice because it was too cold, dry, hot, up,
down, left, right, is wishful thinking.... In spring and fall get the
carb heat on early, lean it out aggressively before pulling the
throttle, and goose the engine every 20 seconds to keep it warm...

denny

[Jonathan Goodish]

In article . com>,
"Denny" > wrote:
> venturi... . And a Lycoming will ice up... I had an engine on Fat
> Albert go limp at 11,500 feet over top of the Detroit B on a winter
> day, and it was 25 degrees at our altitude...

A Lycoming with the carb mounted to the oil pan will ice up, but it is
ironically more likely in cruise than in a low-power configuration. The
exceptions that I've seen involve extended power-off glides, and
extended taxis where the engine has not yet reached operating
temperature for the day.


JKG

[Jim Burns]

Here's instance #2 for ya Jay.

A Dakota on our field was owned by a VFR only pilot. Last summer on a trip
from STE to GRB and back, he reported having carb ice 3 times during his
trip. He questioned that it was really carb ice, but said that each time
the engine started to sputter, carb heat smoothed out the roughness in text
book fashion. Each time, the engine then ran smoothly for awhile then got
gradually rougher until carb heat was applied again.

I was at the airport when he returned and reported the problem to the
mechanic. To satisfy the pilot, the mechanic looked over the airplane and
found nothing wrong. It was simply the effect of a very humid day.

Jim

[RST Engineering]

He did NOT say that the temperature was BELOW freezing, he said that the
temperature was ABOUT freezing, which is a prime candidate for carb ice. He
also mentioned nothing about visible moisture (clouds) which would be
another clue that the air DID contain sufficient moisture to cause carb ice.

And yes, engine restart on the taxiway after a dead stick iced carb is the
norm, as the engine compartment warms up with hot cylinders and no cold air
moving over them. Carb warms up REAL quick that way.

Jim


"cjcampbell" > wrote in message
oups.com...


> The reason I do not think it was carb ice is that the weather was below
> freezing, which means that the air was probably relatively dry and it
> may even have been too cold for carb ice to form (the air would have to
> have liquid water precipitate out of it to cause carb ice, meaning that
> the air would have to be warmed in the carburetor, not cooled, and
> somehow also exceed 100% humidity in the process

[Orval Fairbairn]

In article >,
"RST Engineering" > wrote:

> He did NOT say that the temperature was BELOW freezing, he said that the
> temperature was ABOUT freezing, which is a prime candidate for carb ice. He
> also mentioned nothing about visible moisture (clouds) which would be
> another clue that the air DID contain sufficient moisture to cause carb ice.
>
> And yes, engine restart on the taxiway after a dead stick iced carb is the
> norm, as the engine compartment warms up with hot cylinders and no cold air
> moving over them. Carb warms up REAL quick that way.
>
> Jim
>
>
> "cjcampbell" > wrote in message
> oups.com...
>
>
> > The reason I do not think it was carb ice is that the weather was below
> > freezing, which means that the air was probably relatively dry and it
> > may even have been too cold for carb ice to form (the air would have to
> > have liquid water precipitate out of it to cause carb ice, meaning that
> > the air would have to be warmed in the carburetor, not cooled, and
> > somehow also exceed 100% humidity in the process

Loose nuts on the studs attaching the carburetor to the engine are NOT
all that uncommon! I have known of several. That will cause the engine
to stop at low power/idle settings!

[Brian]

I have had exactly that happen to me in a Citabria with a Lycoming
engine.

I suspect carb ice. Intesting thing about carb ice is in above freezing
temperatues as soon as the engine stops turning the Ice starts melting.
It would not have to completely melt, only enough to let the engine
restart.

Clearing the engine is mostly just a good way to ensure it is still
running.

Brian
CFIIG/ASEL

[RST Engineering]

Yes, but that engine is a bitch to restart and will quit as soon as you go
to idle. OP said that restart was easy and wouldn't quit again. I still
think it was carb ice.

Jim



"Orval Fairbairn" > wrote in message
news:orfairbairn-
>
> Loose nuts on the studs attaching the carburetor to the engine are NOT
> all that uncommon! I have known of several. That will cause the engine
> to stop at low power/idle settings!

[Peter R.]

Happy Dog > wrote:

> I was flying into La Guardia on Air Canada and I saw a Bonanza rolling out
> with the engine stopped. By total coincidence, exiting the plane, I got a
> call from that pilot's instructor who'd briefed the pilot on this X/C. He
> said that there was a known problem with that plane and, I think, said that
> it was not an uncommon problem with that type of plane. Odd thing,
> coincidence.

My fuel-injected, turbo-normalized Bonanza had a newly rebuilt engine
installed last February. Upon completion of the work, I took the aircraft
up for the proper first flight break-in. When I landed, the engine quit
just as I touched down (low idle) on the runway.

I was able to restart and taxied back to talk to the mechanic. He adjusted
the low-idle mixture so I took the aircraft up for the second flight
break-in. Again, upon landing the engine quit.

Suspecting something else now, the mechanic ran the aircraft on the ground
and was able to duplicate the problem. He then suspected the fuel pump so
he took it off and sent it back to the company who supplied it to the
engine rebuilder for inspection. The fuel pump inspectors discovered metal
shavings inside the fuel pump that were cutting off fuel flow at low idle.
That opened up an entire finger pointing session. Nice...

The source of the shavings was never identified but it was concluded that
somehow they were introduced when the engine was on the test cell.


--
Peter
























----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----

[nrp]

I agree it is probably carb ice & a remelt situation. My 150 hp 172M
will actually ice up to a limit quite quickly under the right
conditions. Note that OP probably had a very low power approach over
his obstacle in which case there would be little heat available for the
carb heat stove.

Those who say Lycomings won't ice up just haven't encountered the right
conditions - yet.

[The Visitor]

Is this an injected engine?





Jase Vanover wrote:
> I had a situation yesterday at the end of my local "just because" flight
> (you know, one of those where you really have no place to go but the weather
> is favourable and you just want to go flying).
>
> Was flying a rental 172. Took off like a rocket (lightly loaded solo...
> cold air about freezing), tooled around practicing stalls, steep turns, etc.
> Headed back to the pattern and did a couple of touch and goes. On my final
> landing, I declared a full stop, and decided I would practice a short field
> landing. I cleared the "imaginary" 50 ft. obstacle, dropped the last notch
> of flaps and cut power... and the engine quit. No issues, because I had the
> runway made (I didn't even realize that the engine had quit until rolling on
> the runway... I knew something sounded different, but the prop was still
> windmilling and I was concentrating on the flare).
>
> I rolled out and the prop stopped, and I called traffic (uncontrolled
> airport) to let them know I was a sitting duck. Checked the primer
> (locked), mixture (full rich), fuel selector (both... and lots of fuel... I
> filled up with only just over an hour of flight since), and restarted with
> no problems and taxied off the runway.
>
> Though it turned out to be no danger, I couldn't help but feel a little
> disconcerted. A low level power off descent away from the airport could
> have had a more serious outcome, or what if I misjudged and didn't have the
> runway made when I cut power?
>
> I taxied to the maintenance hanger (after being directed there by the FBO
> via radio notification of the situation), and explained what happened to the
> maintenance guy. He said that there is a stop on the throttle to keep the
> idle setting from being too low that probably needed adjustment. Even so,
> during shutdown (after restarting), idle setting on the throttle was still
> 800 - 900 RPM, which should be enough to keep the engine running I would
> think.
>
> Anyone else experienced this and can share their thoughts? I'm about a 60
> hour pilot, so not much experience.
>
>
>
>
>

[Jay Honeck]

> A Dakota on our field was owned by a VFR only pilot. Last summer on a trip
> from STE to GRB and back, he reported having carb ice 3 times during his
> trip. He questioned that it was really carb ice, but said that each time
> the engine started to sputter, carb heat smoothed out the roughness in text
> book fashion. Each time, the engine then ran smoothly for awhile then got
> gradually rougher until carb heat was applied again.
>
> I was at the airport when he returned and reported the problem to the
> mechanic. To satisfy the pilot, the mechanic looked over the airplane and
> found nothing wrong. It was simply the effect of a very humid day.

This happened in SUMMER?

Very weird. In our plane, the carb heat is checked prior to take-off,
and never touched again. In fact, I've only activated carb heat once
in flight (in ten years and 1500 hours) in ANY flavored Cherokee -- and
that was just an experiment.

Cessnas are another animal altogether, of course.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

[Dale]

In article . com>,
"nrp" > wrote:

> I agree it is probably carb ice & a remelt situation. My 150 hp 172M
> will actually ice up to a limit quite quickly under the right
> conditions. Note that OP probably had a very low power approach over
> his obstacle in which case there would be little heat available for the
> carb heat stove.
>
> Those who say Lycomings won't ice up just haven't encountered the right
> conditions - yet.
>

I've never gotten carb ice at a low power setting, it has always been at
cruise or even takeoff power.

I put a carb temp guage in my 182..at low power settings the carb temp
is near ambient air temp. It's only when you start sucking a lot of air
through the carb that the temps drop.

--
Dale L. Falk

There is nothing - absolutely nothing - half so much worth doing
as simply messing around with airplanes.

http://home.gci.net/~sncdfalk/flying.html

[Jim Burns]

Yep, happened last summer. Surface temps were around 70. It totally
freaked this guy out. So bad that it became one of the reasons he sold the
plane. (not a valid reason in my book, but to each his own.)

From a teaching stand point, especially to renter pilots, I've always taught
to use it on landings. Keep the procedures as similar as possible between
airplanes unless there is a good reason to deviate.

I've only needed carb heat once. It was IMC, in the spring, in an Archer.

Jim

"Jay Honeck" > wrote in message
oups.com...
>
> This happened in SUMMER?
>
> Very weird. In our plane, the carb heat is checked prior to take-off,
> and never touched again. In fact, I've only activated carb heat once
> in flight (in ten years and 1500 hours) in ANY flavored Cherokee -- and
> that was just an experiment.
>
> Cessnas are another animal altogether, of course.
> --
> Jay Honeck
> Iowa City, IA
> Pathfinder N56993
> www.AlexisParkInn.com
> "Your Aviation Destination"
>

[RST Engineering]

The OP said this was a 172.

Jim


"The Visitor" > wrote in message
...
> Is this an injected engine?

[Bill Zaleski]

On Mon, 24 Oct 2005 15:26:19 -0700, "RST Engineering"
> wrote:

>The OP said this was a 172.
>
>Jim
>
>
>"The Visitor" > wrote in message
...
>> Is this an injected engine?

Some are.
>

[[email protected]]

>The reason I do not think it was carb ice is that the weather was below
>freezing, which means that the air was probably relatively dry and it
>may even have been too cold for carb ice to form (the air would have to
>have liquid water precipitate out of it to cause carb ice, meaning that
>the air would have to be warmed in the carburetor, not cooled, and
>somehow also exceed 100% humidity in the process).

The textbooks will tell you that water can exist in liquid form
down to minus 20 degrees Celsius, or about minus 3 degrees F. We have
encountered carb icing at these temperatures here in Western Canada, in
clear air. Carb ice can also form from dissolved water in the gasolne,
and all gas has at least a small amount of water in it. It can't be
seen unless the temp gets really low, where it finally clumps up and
forms snowflakes in the fuel.

>I put a carb temp guage in my 182..at low power settings the carb temp
>is near ambient air temp. It's only when you start sucking a lot of air
>through the carb that the temps drop.

The 172's Lycoming will ice up easily enough after startup, while
idling, as will many other engines. There is a massive pressure drop as
the air squeezes past the throttle plate at idle, therefore a large
temperature drop, and ice WILL form there. Seen it many times since I
began flying in 1973. Unless the ambient temperature is very high, very
low, or the air is very dry, or that carb is plenty warm, carb ice can
form. It can catch the unwary when they fly in climates different from
what they're used to.

Dan

[Viperdoc]

I have had an engine quit multiple times in my twin on roll out after
pulling the power back to idle. It ended up being an idle mixture
adjustment, not carb ice (fuel injected). The other possibility was sloppy
linkage in the throttle, but this was tight, and testing the fuel pressure
showed it to be too low at idle.

Don't assume it has to be carb ice.

[Matt Whiting]

George Patterson wrote:

> Longworth wrote:
>
>> It sounded like carb ice problem to me.
>
>
> If it were carb ice, the engine would not have restarted easily.
>
> George Patterson
> Drink is the curse of the land. It makes you quarrel with your
> neighbor.
> It makes you shoot at your landlord. And it makes you miss him.

As I recall, the OP said the engine was restarted after landing. The
warmth of the engine could have easily melted the ice during the final
approach and landing allowing a restart on the ground.

Matt

[Matt Whiting]

Jose wrote:

> I had a situation in the Shenandoah Valley where, during runup when I
> checked smooth operation at idle, the engine quit. It started up easily
> enough, but quit again at idle. Taxiied back, went to the shop and they
> poked around with the plugs and a few other things, finding nothing.
> Their theory was that it was carb ice.
>
> Never had carb ice on the ground before.

The carburetor doesn't know whether it is on the ground or in the air. :-)

Matt

[Matt Whiting]

Dale wrote:

> In article . com>,
> "nrp" > wrote:
>
>
>>I agree it is probably carb ice & a remelt situation. My 150 hp 172M
>>will actually ice up to a limit quite quickly under the right
>>conditions. Note that OP probably had a very low power approach over
>>his obstacle in which case there would be little heat available for the
>>carb heat stove.
>>
>>Those who say Lycomings won't ice up just haven't encountered the right
>>conditions - yet.
>>
>
>
> I've never gotten carb ice at a low power setting, it has always been at
> cruise or even takeoff power.
>
> I put a carb temp guage in my 182..at low power settings the carb temp
> is near ambient air temp. It's only when you start sucking a lot of air
> through the carb that the temps drop.

Which is because you are then also sucking a lot of fuel through the
carb! :-)

Matt

[Mark T. Dame]

Jay Honeck wrote:
>
> Very weird. In our plane, the carb heat is checked prior to take-off,
> and never touched again. In fact, I've only activated carb heat once
> in flight (in ten years and 1500 hours) in ANY flavored Cherokee -- and
> that was just an experiment.

The only time I've experienced carb ice was in an Archer. Of course I
was at 11,000 ft in cool moist air, but I had never experienced it
before, so I was caught by surprise. I noticed that my IAS was slowly
dropping (like 3-4 kts in the last 15 minutes). The throttle was still
firewalled (which at 11K feet, is ~55%), but I looked at the tach, and
noticed that my RPMs had dropped too. (This was before I was instrument
rated, so I didn't pay as close attention to the gauges as I should
have.) Just as I started to consider panicking, I thought about trying
the carb heat. That resulted in an immediate revolt by the engine as it
swallowed the water from the carb. It actually sounded a lot like an
ice-crusher... After about a minute everything was running smooth again
and I turned off the carb heat. For the rest of the flight I paid
closer attention to tach and had to apply the carb heat several more
times (although less of an event than the first time). Eventually, I
just left the carb heat on for the remainder of the flight.

But I've never had a problem since, so it is not a common event at all.
Sometimes the conditions are just right.


-m
--
## Mark T. Dame >
## VP, Product Development
## MFM Software, Inc. (http://www.mfm.com/)
"Madness takes its toll. Please have exact change."

[Mark T. Dame]

Peter R. wrote:
>
> My fuel-injected, turbo-normalized Bonanza had a newly rebuilt engine
> installed last February. Upon completion of the work, I took the aircraft
> up for the proper first flight break-in. When I landed, the engine quit
> just as I touched down (low idle) on the runway.
>
> I was able to restart and taxied back to talk to the mechanic. He adjusted
> the low-idle mixture so I took the aircraft up for the second flight
> break-in. Again, upon landing the engine quit.
>
> Suspecting something else now, the mechanic ran the aircraft on the ground
> and was able to duplicate the problem. He then suspected the fuel pump so
> he took it off and sent it back to the company who supplied it to the
> engine rebuilder for inspection. The fuel pump inspectors discovered metal
> shavings inside the fuel pump that were cutting off fuel flow at low idle.
> That opened up an entire finger pointing session. Nice...
>
> The source of the shavings was never identified but it was concluded that
> somehow they were introduced when the engine was on the test cell.

I had a similar situation with a carburetor on the club's Archer. It
had been at the maintenance shop for some carb work. After ground
testing and a short flight around the patch, everything seemed be
working fine. So I took off and flew home. On final my descent rate
was a little fast, so I went to tweak the throttle and nothing happened.
Since I was less than a half a mile from the threshold with plenty of
altitude, it was no big deal to dead stick it in. I actually had enough
speed left on landing that had I been going the other way I probably
could have made it off the runway. (The runway at our airport has a
slight grade and I was landing uphill.) Instead I rolled to a stop
almost exactly mid-way down the runway and had to call for a tow because
the engine wouldn't restart.

It was discovered afterward that the shop that had worked on the carb
had gotten a washer stuck between the top half and bottom half of the
carb that prevented the float from properly shutting off the fuel flow.
The result was a flooded engine on final.


-m
--
## Mark T. Dame >
## VP, Product Development
## MFM Software, Inc. (http://www.mfm.com/)
"And so it was only with the advent of pocket computers that the
startling truth became finally apparent, and it was this:

Numbers written on restaurant checks within the confines of
restaurants do not follow the same mathematical laws as numbers
written on any other pieces of paper in any other parts of the
Universe."
-- Life, the Universe, and Everything, Douglas Adams

[[email protected]]

Here it is: a graph I was hoping to find on the 'net that shows the
temperature ranges and dewpoint/humidites at which icing can occur.
Note that the range extends from well below freezing to over 100
degrees F. This graph will apply to avgas; mogas has a higher
volatility (evaporation rate) and can cause icing outside these
parameters.

http://www.wsaa.net/icing.htm

Icing can also occur in very cold temps if carb heat IS used: ice
crystals in the air can melt as the incoming air is heated, collect on
the throttle plate and other parts, and freeze due to the pressure drop
and evaporative cooling.

Dan

[nrp]

I wondere how much of a temperature gradient might be present in the
fuel/air stream at the sense point of a carb air temp gage. A lot of
things are happening quickly as air comes thru the air intake (heat off
only) or heat system, and then on to the carb heat box valve system
before it goes into the carb venturi, where the air is expanded & the
fuel added.

I agree that it is better to have an air temp gage but maybe one should
be a little suspicious of it.

[The Visitor]

RST Engineering wrote:

> The OP said this was a 172.
>
Some are. So I have to ask.

Anyhow, if so it may be linked to a problem in the fuel pump. Mine was
actually missing a connecting spring (from factory) that did not allow
it to maintain a fuel flow at idle settings. So for years I go around
with it a bit high on the idle and sometimes on rollout, just at the end
and starting to turn off, the engine would shake and I would hit the
electric pump to bring it back. I actually had it down to a fine art.
The problem was only found when the pump was pulled and sent out to have
a seal changed.

John

[RST Engineering]

"The Visitor" > wrote in message
...
>
>
> RST Engineering wrote:
>
>> The OP said this was a 172.
>>
> Some are. So I have to ask.


Without me having to go to the TCs and do a search, can somebody please tell
me what series of 172s were injected?


>
> Anyhow, if so it may be linked to a problem in the fuel pump.


And again the models of 172s that have fuel pumps?


Jim

[JohnK]

All of the 172's at my FBO are FI, but they are all 1999 and newer.
Probably doesn't answer your question too well. Always gets me when I
go to pull on carb heat during a descent and it's not there.

John K.

[Peter Clark]

On Tue, 25 Oct 2005 13:14:58 -0700, "RST Engineering"
> wrote:

>
>"The Visitor" > wrote in message
...
>>
>>
>> RST Engineering wrote:
>>
>>> The OP said this was a 172.
>>>
>> Some are. So I have to ask.
>
>
>Without me having to go to the TCs and do a search, can somebody please tell
>me what series of 172s were injected?

I think it's any of the "new" ones - 1996 and newer R and S models.

>>
>> Anyhow, if so it may be linked to a problem in the fuel pump.
>
>
>And again the models of 172s that have fuel pumps?

1996 and newer - R and S models have electric fuel pumps, certain
serial numbers of which also have a SB out against it for something to
do with a diaphragm issue and inspection thereof if memory serves.

[Allen]

"RST Engineering" > wrote in message
...
>
> "The Visitor" > wrote in message
> ...
>>
>>
>> RST Engineering wrote:
>>
>>> The OP said this was a 172.
>>>
>> Some are. So I have to ask.
>
>
> Without me having to go to the TCs and do a search, can somebody please
> tell me what series of 172s were injected?
>
>
>>
>> Anyhow, if so it may be linked to a problem in the fuel pump.
>
>
> And again the models of 172s that have fuel pumps?
>

Hawk XP is injected but it has a 195 hp Continental 10-360-K in it.

Allen

[The Visitor]

The newer 172's are fuel injected. They will have an engine driven fuel
pump and and electric one.

John








RST Engineering wrote:

> "The Visitor" > wrote in message
> ...
>
>>
>>RST Engineering wrote:
>>
>>
>>>The OP said this was a 172.
>>>
>>
>>Some are. So I have to ask.
>
>
>
> Without me having to go to the TCs and do a search, can somebody please tell
> me what series of 172s were injected?
>
>
>
>>Anyhow, if so it may be linked to a problem in the fuel pump.
>
>
>
> And again the models of 172s that have fuel pumps?
>
>
> Jim
>
>

[Jase Vanover]

Sorry so late getting back to the group... away travelling on business.

Carb heat had been on since downwind. I was taught to put carb heat on as
part of my downwind checks every time, when doing manouvers at lower
throttle settings, and approximately every 15 minutes during cruise... which
I'm pretty faithful to. It is also standard part of my runup (both at 1700
RPM and at idle).

This was my third circuit. Carb heat was applied during downwind for all
three of them.

You make a good point that when I did my shutdown after restarting, I didn't
have carb heat on, so the engine not quiting and showing 800-900 could be
because carb heat wasn't on... though it didn't quit on my first two
landings either.


"Rob" > wrote in message
oups.com...
>
> Jase Vanover wrote:
>> I taxied to the maintenance hanger (after being directed there by the FBO
>> via radio notification of the situation), and explained what happened to
>> the
>> maintenance guy. He said that there is a stop on the throttle to keep
>> the
>> idle setting from being too low that probably needed adjustment. Even
>> so,
>> during shutdown (after restarting), idle setting on the throttle was
>> still
>> 800 - 900 RPM, which should be enough to keep the engine running I would
>> think.
>
> Did you have the carb heat on when the engine died in the air and off
> when you couldn't make the engine fail on the ground? Maybe the idle
> setting was low enough that the additional RPM loss due to the carb
> heat made a difference.
>
> -R
>

[cjcampbell]

Happy Dog wrote:
>
> Power changes are taught as SOP for climbs and descents. If what you say is
> true (and I don't know it isn't, but I doubt it) engine outs could be
> reduced by climbing or descending without power changes. Or at least
> deferred until landing.

That would be a neat trick. :-P

[Tom]

Carb ice ...


"Jase Vanover" > wrote in message
...
>I had a situation yesterday at the end of my local "just because" flight
>(you know, one of those where you really have no place to go but the
>weather is favourable and you just want to go flying).
>
> Was flying a rental 172. Took off like a rocket (lightly loaded solo...
> cold air about freezing), tooled around practicing stalls, steep turns,
> etc. Headed back to the pattern and did a couple of touch and goes. On my
> final landing, I declared a full stop, and decided I would practice a
> short field landing. I cleared the "imaginary" 50 ft. obstacle, dropped
> the last notch of flaps and cut power... and the engine quit. No issues,
> because I had the runway made (I didn't even realize that the engine had
> quit until rolling on the runway... I knew something sounded different,
> but the prop was still windmilling and I was concentrating on the flare).
>
> I rolled out and the prop stopped, and I called traffic (uncontrolled
> airport) to let them know I was a sitting duck. Checked the primer
> (locked), mixture (full rich), fuel selector (both... and lots of fuel...
> I filled up with only just over an hour of flight since), and restarted
> with no problems and taxied off the runway.
>
> Though it turned out to be no danger, I couldn't help but feel a little
> disconcerted. A low level power off descent away from the airport could
> have had a more serious outcome, or what if I misjudged and didn't have
> the runway made when I cut power?
>
> I taxied to the maintenance hanger (after being directed there by the FBO
> via radio notification of the situation), and explained what happened to
> the maintenance guy. He said that there is a stop on the throttle to keep
> the idle setting from being too low that probably needed adjustment. Even
> so, during shutdown (after restarting), idle setting on the throttle was
> still 800 - 900 RPM, which should be enough to keep the engine running I
> would think.
>
> Anyone else experienced this and can share their thoughts? I'm about a 60
> hour pilot, so not much experience.
>
>
>
>
>

[Tom]

An A&P and/or IA made a mistake working on a engine? To hear them tell, they
are the "experts" and you should never work on your own plane nor should you
be anywhere within 100 miles of the shop when they work on them.

Tom

"Mark T. Dame" > wrote in message
...
> Peter R. wrote:
>>
>> My fuel-injected, turbo-normalized Bonanza had a newly rebuilt engine
>> installed last February. Upon completion of the work, I took the
>> aircraft
>> up for the proper first flight break-in. When I landed, the engine quit
>> just as I touched down (low idle) on the runway. I was able to restart
>> and taxied back to talk to the mechanic. He adjusted
>> the low-idle mixture so I took the aircraft up for the second flight
>> break-in. Again, upon landing the engine quit.
>>
>> Suspecting something else now, the mechanic ran the aircraft on the
>> ground
>> and was able to duplicate the problem. He then suspected the fuel pump
>> so
>> he took it off and sent it back to the company who supplied it to the
>> engine rebuilder for inspection. The fuel pump inspectors discovered
>> metal
>> shavings inside the fuel pump that were cutting off fuel flow at low
>> idle.
>> That opened up an entire finger pointing session. Nice...
>>
>> The source of the shavings was never identified but it was concluded that
>> somehow they were introduced when the engine was on the test cell.
>
> I had a similar situation with a carburetor on the club's Archer. It had
> been at the maintenance shop for some carb work. After ground testing and
> a short flight around the patch, everything seemed be working fine. So I
> took off and flew home. On final my descent rate was a little fast, so I
> went to tweak the throttle and nothing happened. Since I was less than a
> half a mile from the threshold with plenty of altitude, it was no big deal
> to dead stick it in. I actually had enough speed left on landing that had
> I been going the other way I probably could have made it off the runway.
> (The runway at our airport has a slight grade and I was landing uphill.)
> Instead I rolled to a stop almost exactly mid-way down the runway and had
> to call for a tow because the engine wouldn't restart.
>
> It was discovered afterward that the shop that had worked on the carb had
> gotten a washer stuck between the top half and bottom half of the carb
> that prevented the float from properly shutting off the fuel flow. The
> result was a flooded engine on final.
>
>
> -m
> --
> ## Mark T. Dame >
> ## VP, Product Development
> ## MFM Software, Inc. (http://www.mfm.com/)
> "And so it was only with the advent of pocket computers that the
> startling truth became finally apparent, and it was this:
>
> Numbers written on restaurant checks within the confines of
> restaurants do not follow the same mathematical laws as numbers
> written on any other pieces of paper in any other parts of the
> Universe."
> -- Life, the Universe, and Everything, Douglas Adams

[Tom]

This is about as clear as it can be described.

Tom

"Denny" > wrote in message
oups.com...
> Carb ice, period!
>
> If it was a fuel pump, mag, loose throttle stop, stuck lifters, etc.,
> none of these things cure themselves after the engine stops. An iced
> up air filter might melt off, but not in seconds... Carb ice is the one
> thing that will clear within seconds inside of a warm engine once the
> windmilling stops, which stops it pulling more cold air across the
> venturi... . And a Lycoming will ice up... I had an engine on Fat
> Albert go limp at 11,500 feet over top of the Detroit B on a winter
> day, and it was 25 degrees at our altitude...
> A few years back I lost an old high school classmate from Caro,
> Michigan when he went for a student night flight in a Cherokee, iced up
> and then stalled it before he got to the ground...
>
> Claiming it couldn't be carb ice because it was too cold, dry, hot, up,
> down, left, right, is wishful thinking.... In spring and fall get the
> carb heat on early, lean it out aggressively before pulling the
> throttle, and goose the engine every 20 seconds to keep it warm...
>
> denny
>

[Tom]

A lot of 0-300's in the older 172's have fuel pumps, I am not too sure why
though. Maybe because of the 6 cylinders?

Tom

"RST Engineering" > wrote in message
...
>
> "The Visitor" > wrote in message
> ...
>>
>>
>> RST Engineering wrote:
>>
>>> The OP said this was a 172.
>>>
>> Some are. So I have to ask.
>
>
> Without me having to go to the TCs and do a search, can somebody please
> tell me what series of 172s were injected?
>
>
>>
>> Anyhow, if so it may be linked to a problem in the fuel pump.
>
>
> And again the models of 172s that have fuel pumps?
>
>
> Jim
>

[Jase Vanover]

Carb heat was on for at least a minute or two (applied late downwind, and
the engine quit only in the flare on landing).

I'm not trying to say I know what caused it, just that I struggle to
understand how it could be carb ice with heat on, at prox freezing plus a
couple degrees, and with carb heat apparently working per runup indications.


"Denny" > wrote in message
oups.com...
> Carb ice, period!
>
> If it was a fuel pump, mag, loose throttle stop, stuck lifters, etc.,
> none of these things cure themselves after the engine stops. An iced
> up air filter might melt off, but not in seconds... Carb ice is the one
> thing that will clear within seconds inside of a warm engine once the
> windmilling stops, which stops it pulling more cold air across the
> venturi... . And a Lycoming will ice up... I had an engine on Fat
> Albert go limp at 11,500 feet over top of the Detroit B on a winter
> day, and it was 25 degrees at our altitude...
> A few years back I lost an old high school classmate from Caro,
> Michigan when he went for a student night flight in a Cherokee, iced up
> and then stalled it before he got to the ground...
>
> Claiming it couldn't be carb ice because it was too cold, dry, hot, up,
> down, left, right, is wishful thinking.... In spring and fall get the
> carb heat on early, lean it out aggressively before pulling the
> throttle, and goose the engine every 20 seconds to keep it warm...
>
> denny
>

[Jase Vanover]

I maintained low power (maybe 1300 RPM) on final, but not idle. Approaching
the runway (was simulating a short field landing) and clearing the
ubiquitous 50 ft. obstacle, I cut power to idle and dropped my last notch of
flaps. It was a matter of several seconds from this point to flare and the
engine quitting.

I would think that at low speed (prox 60 kts approach), moderate temps (just
above freezing... all is relative ;-) and 1300 RPM (and carb heat applied)
there would be enough heat to ward off carb ice, but I'm admittedly short on
experience with this sort of thing.

"nrp" > wrote in message
oups.com...
>I agree it is probably carb ice & a remelt situation. My 150 hp 172M
> will actually ice up to a limit quite quickly under the right
> conditions. Note that OP probably had a very low power approach over
> his obstacle in which case there would be little heat available for the
> carb heat stove.
>
> Those who say Lycomings won't ice up just haven't encountered the right
> conditions - yet.
>

[Dale]

In article >,
"Jase Vanover" > wrote:


>
> Carb heat had been on since downwind. I was taught to put carb heat on as
> part of my downwind checks every time, when doing manouvers at lower
> throttle settings, and approximately every 15 minutes during cruise... which
> I'm pretty faithful to. It is also standard part of my runup (both at 1700
> RPM and at idle).
>
> This was my third circuit. Carb heat was applied during downwind for all
> three of them.
>
> You make a good point that when I did my shutdown after restarting, I didn't
> have carb heat on, so the engine not quiting and showing 800-900 could be
> because carb heat wasn't on... though it didn't quit on my first two
> landings either.
>

Carb ice is funny sometimes. Was doing a bunch of T&Gs in a 152. As
you, Carb Heat on downwind, push it off after pushing the throttle in on
takeoff. On my 7th or 8th "GO" the engine lost power and ran rough at
about 300' and quit as I made a right 270 back to the intersecting
runway. Made the runway, got a restart after a few moments, it ran real
rough for a bit then smoothed out. Shop checked it and found nothing
wrong, we assume it was carb ice.

--
Dale L. Falk

There is nothing - absolutely nothing - half so much worth doing
as simply messing around with airplanes.

http://home.gci.net/~sncdfalk/flying.html

[[email protected]]

>Carb ice is funny sometimes. Was doing a bunch of T&Gs in a 152. As
>you, Carb Heat on downwind, push it off after pushing the throttle in on
>takeoff. On my 7th or 8th "GO" the engine lost power and ran rough at
>about 300' and quit as I made a right 270 back to the intersecting
>runway. Made the runway, got a restart after a few moments, it ran real
>rough for a bit then smoothed out. Shop checked it and found nothing
>wrong, we assume it was carb ice.

More likely the engine had loaded up with raw fuel. With carb
heat on, the mixture gets pretty rich, and with the throttle closed
there is very little airflow through the engine. Fuel can puddle in the
intake manifold, and upon opening the throttle all that gasoline is
sucked into the cylinders and floods them. It's worse if you shut the
carb heat off first, as the cold air reduces the vaporization of the
fuel.
Don't make long power-off glides when it's cold and with carb
heat on. Clear the engine often, and make sure it's ready to run if you
need it.

Dan

[Morgans]

> wrote

> Don't make long power-off glides when it's cold and with carb
> heat on. Clear the engine often, and make sure it's ready to run if you
> need it.


That sure is different than the normal advice, isn't it?
--
Jim in NC

[Dale]

In article . com>,
wrote:


>
> More likely the engine had loaded up with raw fuel. With carb
> heat on, the mixture gets pretty rich, and with the throttle closed
> there is very little airflow through the engine. Fuel can puddle in the
> intake manifold, and upon opening the throttle all that gasoline is
> sucked into the cylinders and floods them. It's worse if you shut the
> carb heat off first, as the cold air reduces the vaporization of the
> fuel.
> Don't make long power-off glides when it's cold and with carb
> heat on. Clear the engine often, and make sure it's ready to run if you
> need it.


No that isn't what happened. It was fine for the first couple hundered
feet of the climb. If it had loaded up it would have stumbled as I
added power.

--
Dale L. Falk

There is nothing - absolutely nothing - half so much worth doing
as simply messing around with airplanes.

http://home.gci.net/~sncdfalk/flying.html

[Private]

"Tom" > wrote in message
...
> An A&P and/or IA made a mistake working on a engine? To hear them tell,
> they are the "experts" and you should never work on your own plane nor
> should you be anywhere within 100 miles of the shop when they work on
> them.
>

AMEs think anything accessible to a pilot is controlled by an idiot.
Pilots think that AMEs are trying to kill them.
A schizophrenic is a pilot who is also an AME

Happy landings,

[RST Engineering]

Sigh.

Jim
Comm'l. Inst. CFI Airplane & Glider
A&P IA

Roses are red
Violets are blue
I'm schizophrenic
And so am I.



"Private" > wrote in message
news:40R8f.336700$oW2.18373@pd7tw1no...
>
> AMEs think anything accessible to a pilot is controlled by an idiot.
> Pilots think that AMEs are trying to kill them.
> A schizophrenic is a pilot who is also an AME

[Private]

cheers, ROTFL

"RST Engineering" > wrote in message
...
> Sigh.
>
> Jim
> Comm'l. Inst. CFI Airplane & Glider
> A&P IA
>
> Roses are red
> Violets are blue
> I'm schizophrenic
> And so am I.
>
>
>
> "Private" > wrote in message
> news:40R8f.336700$oW2.18373@pd7tw1no...
>>
>> AMEs think anything accessible to a pilot is controlled by an idiot.
>> Pilots think that AMEs are trying to kill them.
>> A schizophrenic is a pilot who is also an AME
>
>
>