Prop Feathers and Engine Shuts down after landing????????

Today I was flying my Twin Comanche PA30 everything was great until after
landing. Once I had the wheels on the ground I pulled the power back to idle,
about three seconds or so after I pulled the power back the prop feathered and
the engine shut down. I let the engine cool down for about 30 min then started
the engine right up. Everything was running great. So I took off and flew
around for a while then came back to land, this time after I landed I put
the power back up to 1500 rpm, the oil temp was right below redline the oil
was at 50psi then the prop feathered and the engine shut down again. This also
happened to me yesterday. Every time I land the prop feathers and the engine
shuts down . Everythings always great until after landing. I only have 40
hours on the engine. Could anyone please help me out? Has this ever happened
to anyone before? Does anyone have any ideas on what it could be thanks for
everyone’s help.

This is only a guess but may make some sense. Some CS props will go full
pitch if oil pressure is lost, others will to to minimum pitch with no oil
pressure. You said that the oil temperature was high. (an indication of low
oil level). Also how is the oil pressure just before it shuts down? Being
at idle already, full pitch could make enough drag to stall the engine.
OTOH, if the engine stalled first, the lack of oil pressure would cause the
prop to feather too. Make sure the oil is the right viscosity too. In planes
with oil inversion systems, it's important that you have the type of prop
that goes to full pitch because the pressure drop during the transition to
inverted would cause an engine overspeed if it was the type that went to
minimum pitch. Not that yours has an inversion system, but it's nice to know
which prop you have. Let me know how you make out, I will be reading the
other replies too but am curious to answer to your problem.
Wayne

"AIR ADVENTURE82" wrote in message
...
Today I was flying my Twin Comanche PA30 everything was great until after
landing. Once I had the wheels on the ground I pulled the power back to
idle,
about three seconds or so after I pulled the power back the prop feathered
and
the engine shut down. I let the engine cool down for about 30 min then
started
the engine right up. Everything was running great. So I took off and
flew
around for a while then came back to land, this time after I landed I
put
the power back up to 1500 rpm, the oil temp was right below redline the
oil
was at 50psi then the prop feathered and the engine shut down again. This
also
happened to me yesterday. Every time I land the prop feathers and the
engine
shuts down . Everythings always great until after landing. I only have
40
hours on the engine. Could anyone please help me out? Has this ever
happened
to anyone before? Does anyone have any ideas on what it could be thanks
for
everyone's help.

Since the original poster indicated they were flying a twin, they most
definitely have a prop which feathers if oil pressure is lost, otherwise
single engine handling could become even more exciting than usual. Of
course, someone somewhere doubtless knows of a counter example. For a
single, the reverse is usually true: the prop goes to fine pitch if you lose
oil pressure.

That being said, high oil temperature and low oil pressure are definitely
clues. What's curious is that you don't see this behavior just idling. If
low oil levels were the culprit, I'd expect the same thing to happen after a
ground runup. I think it's time to talk to an A&P.

mark

"Wayne" wrote in message
...
This is only a guess but may make some sense. Some CS props will go
full
pitch if oil pressure is lost, others will to to minimum pitch with no oil
pressure. You said that the oil temperature was high. (an indication of
low
oil level). Also how is the oil pressure just before it shuts down? Being
at idle already, full pitch could make enough drag to stall the engine.
OTOH, if the engine stalled first, the lack of oil pressure would cause
the
prop to feather too. Make sure the oil is the right viscosity too. In
planes
with oil inversion systems, it's important that you have the type of prop
that goes to full pitch because the pressure drop during the transition to
inverted would cause an engine overspeed if it was the type that went to
minimum pitch. Not that yours has an inversion system, but it's nice to
know
which prop you have. Let me know how you make out, I will be reading the
other replies too but am curious to answer to your problem.
Wayne

"AIR ADVENTURE82" wrote in message
...
Today I was flying my Twin Comanche PA30 everything was great until
after
landing. Once I had the wheels on the ground I pulled the power back to

idle,
about three seconds or so after I pulled the power back the prop
feathered
and
the engine shut down. I let the engine cool down for about 30 min then
started
the engine right up. Everything was running great. So I took off and
flew
around for a while then came back to land, this time after I landed I
put
the power back up to 1500 rpm, the oil temp was right below redline the
oil
was at 50psi then the prop feathered and the engine shut down again.
This
also
happened to me yesterday. Every time I land the prop feathers and the
engine
shuts down . Everythings always great until after landing. I only have
40
hours on the engine. Could anyone please help me out? Has this ever
happened
to anyone before? Does anyone have any ideas on what it could be
thanks
for
everyone's help.

"AIR ADVENTURE82" wrote in message ...
Today I was flying my Twin Comanche PA30 everything was great until after
landing.

What oil are you using? Warm temperatures and a too light weight oil can
cause low pressures.

"Dennis O'Connor" wrote in message ...
Either the prop governor, or the piston in the hub are going to hell in a
handbasket... The engine 'stalls' when the prop goes into feather - I doubt
that there is an engine problem... Sending the governor out for overhual
immediately, would be my inclination...

Actually, it may just be a bad idle mixture setting. My engine when hot used
to stall at idle (frequently rolling out with the throttle at idle). I didn't have a twin,
but I can imagine that the prop would feather during such a sequence in a twin.

Shouldn't the prop feather when you lose oil pressure (on a twin)? Sounds
like the prop is behaving normally to me. More likely you are having some
kind of problem with your throttle.

"Dennis O'Connor" wrote in message
...
Either the prop governor, or the piston in the hub are going to hell in a
handbasket... The engine 'stalls' when the prop goes into feather - I
doubt
that there is an engine problem... Sending the governor out for overhual
immediately, would be my inclination...


Could also be the collar on the crankshaft where the oil gets injected
to drive the prop. There was an article on this recently in "Light Plane
Maintenance", but I can't put my hands on it right now. If the tolerance
is a bit out, there could be a pressure loss sufficient to cause the prop
to feather.

--
Dr. Tony Cox
Citrus Controls Inc.
e-mail:
http://CitrusControls.com/

Piston props (that i have flown) don't feather during shutdown...

It's tough to diagnose a problem on a complex system like a feathering, prop
without being hands on, and without knowing the details of the feathering
mechanism of the model of prop involved, but my initial inclination is
still that it is governor or hub, not engine.... Since then I took a quick
look at the commanche prop hub, and they have a pair of locks that prevent
the blades from feathering when the rpm is below a certain rpm... Those
locks are stuck open or damaged... However, the blades still wouldn't
feather as long as the engine has enough oil pressure for the piston to
overcome the feathering spring... Since he specifically said he had oil
pressure at idle I still am very suspicious that the prop governor has an
internal leak after it gets hot...

Denny


Actually, it may just be a bad idle mixture setting. My engine when hot
used
to stall at idle (frequently rolling out with the throttle at idle). I
didn't have a twin,
but I can imagine that the prop would feather during such a sequence in a
twin.

"Dennis O'Connor" wrote in message ...
Either the prop governor, or the piston in the hub are going to hell in a
handbasket... The engine 'stalls' when the prop goes into feather - I doubt
that there is an engine problem... Sending the governor out for overhual
immediately, would be my inclination...

snip

First off, there is a mechanical high-pitch propeller stop that should
be engaged somewhere 1500 rpm and disengaged 1500 rpm. This stop
enables feathering in-flight, but should prevent it at engine
shut-down. This mechanism has rather obviously failed. How come
across it in the past several times, typically the prop feathers AFTER
the engine is shut down.

Also, if everything is working properly, the oil pressure delivered
from the prop governor to the propeller should keep the propeller
against the fixed low-pitch stop during un-"governed" operation. As
in, unless the governor is sensing the engine rpm is too high (prop
pitch too low) and starts to dump governed oil pressure, the propeller
should stay in the low pitch setting.

If the engine is not supplying sufficient oil volume to the governor,
governor will not supply sufficient pressure to the propeller.

With the propeller feathering at low/no rpm, it must be
inspected/repaired. Then the first step in diagnosing a strange
"governor" problem is ensuring that the proper amount of engine oil is
present at the governor pad. The tooling to accomplish this also makes
it easy to check the prop oil supply path from the other passage at
the governor pad through the front main bearing to the prop galley in
the crankshaft.

TC

wrote in message om...

With the propeller feathering at low/no rpm, it must be
inspected/repaired. Then the first step in diagnosing a strange
"governor" problem is ensuring that the proper amount of engine oil is
present at the governor pad. The tooling to accomplish this also makes
it easy to check the prop oil supply path from the other passage at
the governor pad through the front main bearing to the prop galley in
the crankshaft.

So how do you explain the engine stalling in addition to the feathering?