Engine failure

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.

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.

The OP said this was a 172.

Jim


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

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.

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

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

"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

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.

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.

"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