In-Flight Engine Failure

Well, it happended. I have owned the plane (Piper Turbo Arrow III) for
3 months and the engine failed during climb out on Tuesday. Altitude
was 4400 feet. Luckily, the engine did not entirely quit and I made it
to an airport within 10 miles. TBO was 1000 hours away. Dissapointing!
When we cut the oil filter, it was full of fairly large aluminum and
steel bits of metal. Arg!

(1) Upon examination, the wire into the left magneto was found to be
broken off, just at its connection to the magneto. A mechanic theorized
that it could have grounded to the magento housing. He said that that
could have actually caused a grounding of both magnetos and could have
fouled up the engine firing, and could have contributed to the failure.
Later, he said that he thought that it was just a coincidence that the
left mag wire happened to have been broken when the engine failed due to
some other reason. What do you folks think? Could the two have been
tied togehter?

(2) Now I am faced with having to have the engine overhauled. Growl!
The engine has brand new cylinders on it (well, they have about 100
hours on them) put on by the previous owner. So, I think we want to do
a custom overall of this particular engine. Does that make sense? Are
there different places who do this sort of thing with different
reputations for quality of work? If so, I would like to hear about
recommendations (the engine is a TCM TSIO-360-FB) or perhaps criteria to
use in making a judgement. Also, are there different quality parts or
methods in doing the overhaul that are options that I need to specify
when I ask for the overhaul. In other words, if I can pay 10% more and
get more reliability, then I might like to have the option to do
that...but often, you have to be knowledgeable enough to ask for the
right things.

O. Sami Saydjari wrote:
Well, it happended. I have owned the plane (Piper Turbo Arrow III) for
3 months and the engine failed during climb out on Tuesday. Altitude
was 4400 feet. Luckily, the engine did not entirely quit and I made it
to an airport within 10 miles. TBO was 1000 hours away. Dissapointing!

Way to go. I had a similar engine failure once and was able to make a nearby
airport under partial power with mucho vibration. It's an unforgettable experience.

When we cut the oil filter, it was full of fairly large aluminum and
steel bits of metal. Arg!

(1) Upon examination, the wire into the left magneto was found to be
broken off, just at its connection to the magneto. A mechanic theorized

What wire, the P-lead?

that it could have grounded to the magento housing. He said that that
could have actually caused a grounding of both magnetos and could have
fouled up the engine firing, and could have contributed to the failure.

Seems kinda far-fetched.

Later, he said that he thought that it was just a coincidence that the
left mag wire happened to have been broken when the engine failed due to
some other reason. What do you folks think? Could the two have been
tied togehter?

I don't want to say it's impossible, but it seems unlikely to me. What do I know?

Suppose the magneto could have come loose and spun around, breaking off the
wire, causing gross ignition mistiming and detonation, and leading to the
failure? I dunno, I'm just brainstorming.


(2) Now I am faced with having to have the engine overhauled. Growl!
The engine has brand new cylinders on it (well, they have about 100
hours on them) put on by the previous owner. So, I think we want to do
a custom overall of this particular engine. Does that make sense? Are
there different places who do this sort of thing with different
reputations for quality of work? If so, I would like to hear about

See if you find a copy of "The Major Overhaul", by Kas Thomas. It's out of
print. You might contact Kas himself and ask him where to get a copy.

recommendations (the engine is a TCM TSIO-360-FB) or perhaps criteria to
use in making a judgement. Also, are there different quality parts or
methods in doing the overhaul that are options that I need to specify
when I ask for the overhaul. In other words, if I can pay 10% more and
get more reliability, then I might like to have the option to do
that...but often, you have to be knowledgeable enough to ask for the
right things.

"O. Sami Saydjari" wrote:

(1) Upon examination, the wire into the left magneto was found to be
broken off, just at its connection to the magneto. A mechanic theorized
that it could have grounded to the magento housing. He said that that
could have actually caused a grounding of both magnetos and could have
fouled up the engine firing, and could have contributed to the failure.

If we're talking about the P-lead, I don't see how grounding one would ground out
both mags. In any case, if both mags had been grounded, the engine would not run at
all.

Later, he said that he thought that it was just a coincidence that the
left mag wire happened to have been broken when the engine failed due to
some other reason. What do you folks think? Could the two have been
tied togehter?

I doubt it. Magneto grounding doesn't cause chunks of metal in the oil filter.

George Patterson
This marriage is off to a shaky start. The groom just asked the band to
play "Your cheatin' heart", and the bride just requested "Don't come home
a'drinkin' with lovin' on your mind".

In article ,
"O. Sami Saydjari" wrote:

Well, it happended. I have owned the plane (Piper Turbo Arrow III) for
3 months and the engine failed during climb out on Tuesday. Altitude
was 4400 feet. Luckily, the engine did not entirely quit and I made it
to an airport within 10 miles. TBO was 1000 hours away. Dissapointing!
When we cut the oil filter, it was full of fairly large aluminum and
steel bits of metal. Arg!

(1) Upon examination, the wire into the left magneto was found to be
broken off, just at its connection to the magneto. A mechanic theorized
that it could have grounded to the magento housing. He said that that
could have actually caused a grounding of both magnetos and could have
fouled up the engine firing, and could have contributed to the failure.
Later, he said that he thought that it was just a coincidence that the
left mag wire happened to have been broken when the engine failed due to
some other reason. What do you folks think? Could the two have been
tied togehter?


Very unlikely -- all the P-lead break does is prevent you from shutting
down that mag. It is a good idea to pefrorm a "both off" check when
doing a mag check. That way, you will be able to find a broken P-lead.

You did not state whether or not the engine ran roughly or smoothely
after the failure. From your description of the metal chunks, it would
appear that you had a valve failure, in which case the engine would have
vibrated pretty badly.


(2) Now I am faced with having to have the engine overhauled. Growl!
The engine has brand new cylinders on it (well, they have about 100
hours on them) put on by the previous owner. So, I think we want to do
a custom overall of this particular engine. Does that make sense? Are
there different places who do this sort of thing with different
reputations for quality of work? If so, I would like to hear about
recommendations (the engine is a TCM TSIO-360-FB) or perhaps criteria to
use in making a judgement. Also, are there different quality parts or
methods in doing the overhaul that are options that I need to specify
when I ask for the overhaul. In other words, if I can pay 10% more and
get more reliability, then I might like to have the option to do
that...but often, you have to be knowledgeable enough to ask for the
right things.

(1) Upon examination, the wire into the left magneto was found to be
broken off, just at its connection to the magneto. A mechanic theorized


What wire, the P-lead?


Yes, the P-lead.

Congrats on your cool head and piloting job.....

Thank you. I am a better pilot today because of this experience. The
good news is that I have my (hopefully) once-in-a-flying-career engine
failure behind me

IF you ever have a *zero* mag drop. Don't congratulate
yourself on the condition of the electrical system.... it means you
have a broken "P" lead. A dangerous condition.

I agree. But distinguishing between a 25 RPM mag drop and a zero mag
drop, especially when the RPM needle normally is vibrating a bit, can be
hard (at least for me).

Just out of curiosity, other than having a hot mag (a bad thing, I know,
because the engine can start when turned over by a person...or the
wind), what other failures can be induced by such a problem?




Yeah, BUT.... those 100 hour cylinders might be trash. Can you give
us more information on what actually broke?

Not yet. I am not sure how I will find this out until I am actually
into the overhaul itself. Is there some other diagnostic procedure I
should try?

If a cylinder ingested a
valve, all cylinders on that side are now suspect, perhaps more if you
have a crossover tube. A bent connecting rod may also be possible.
Too many questions.....

Well, all cylinders seemed to have good pressure when it was tested.
because there was both aluminum and steel metal chunks in the oil
filter, the A&P on the spot said that he thought it might have been "the
bearings."

My A&P is going out there to pull the engine on Monday. I should know
more then.

It is a good idea to pefrorm a "both off" check when
doing a mag check. That way, you will be able to find a broken P-lead.

Interesting. I never was taught to do that, but it makes a lot of
sense. Thanks.

You did not state whether or not the engine ran roughly or smoothely
after the failure. From your description of the metal chunks, it would
appear that you had a valve failure, in which case the engine would have
vibrated pretty badly.

Well, here is a little more detail. First, I experienced a 200 RPM
drop. No other obvious symptoms. Then, within 2 minutes, the RPM
dropped another 200 and MP pressure seemed to drop. I boosted throttle.
At that point, I was getting vectors to the nearest airport. Within
about 2 more minutes, I was down into the "yellow arc" of RPM...I think
it was about 2000 RPM. At that point the engine began running rough,
although the vibration was not that bad...just sounded very rough. Then
within about 5 miles of the airport, the oil pressure began dropping
into the yellow arc...35 PSI or so...and dropping. On turning final,
the engine was quite rough, and oil pressure was down to around 10-15
PSI (bottom of the yellow arc), after pulling off the run way, the oil
pressure was at the very bottom of the yellow arc...maybe 5 PSI. I
immediately shutdown. Does that help?



(2) Now I am faced with having to have the engine overhauled. Growl!
The engine has brand new cylinders on it (well, they have about 100
hours on them) put on by the previous owner. So, I think we want to do
a custom overall of this particular engine. Does that make sense? Are
there different places who do this sort of thing with different
reputations for quality of work? If so, I would like to hear about
recommendations (the engine is a TCM TSIO-360-FB) or perhaps criteria to
use in making a judgement. Also, are there different quality parts or
methods in doing the overhaul that are options that I need to specify
when I ask for the overhaul. In other words, if I can pay 10% more and
get more reliability, then I might like to have the option to do
that...but often, you have to be knowledgeable enough to ask for the
right things.

Orval Fairbairn writes:

[...] all the P-lead break does is prevent you from shutting down
that mag. It is a good idea to pefrorm a "both off" check when
doing a mag check. That way, you will be able to find a broken
P-lead.

I've heard mechanics advising against doing this test casually. If
done at even moderate power, it can apparently cause backfiring, which
can in turn create induction system damage. I've seen a C172, one
cylinder of which was burned out shortly after such an episode, due to
extreme lean running resulting from induction cracks.

- FChE

What brand of cylinders are they?

I don't know about the "360" series cylinders, but I would NEVER put
Continentals on if there were any alternative. Continental makes only junk
at this time and their reps are just paid liars.

Karl

I presume they are TCM, but I am not certain. I left the logs with the
mechanic. In my appraisal, it says "8/20/02 Installation of six factor
new cylinder assemblies, part number 654970A4BP. Installed by
Maintenance Express."

-Sami

kage wrote:

What brand of cylinders are they?

I don't know about the "360" series cylinders, but I would NEVER put
Continentals on if there were any alternative. Continental makes only junk
at this time and their reps are just paid liars.

Karl