Real stats on engine failures?

"Peter Duniho" wrote in message ...

But if you look at the same
question over 2000 hours of operation or one or two decades, I suspect that
lack of maintenance will show up as much more of an issue. The lack of oil
changes alone are likely to be a major problem, never mind the myriad of
fixable problems that would normally be detected during routine maintenance.

Lack of use is the big killer. People base a lot of things on how many hours
in service an engine has, but they accumulate problems while sitting as well.

"Ron Natalie" wrote in message
. ..
Lack of use is the big killer. People base a lot of things on how many
hours
in service an engine has, but they accumulate problems while sitting as
well.

Which is why I stipulated both an "hours of operation" and a "calendar time"
measure. Either one is significant, you are correct.

I don't particularly enjoy flying with an engine that's just had some major
work, but I'd sure take that over flying with an engine that's NEVER had ANY
work. And an engine that's gotten a few hours under its belt after
maintenance looks better every flight.

Pete

I guess I don't agree. My experience is that maitenance creates many
problems. I agree that the engine will last longer if you change the oil
more frequently but changing the oil doesn't prevent failures. Routine
maitenance doesn't detect impending connecting rod failures, turbo bearing
about the sieze ect. I have seen and heard of too many oil leaks, fuel
leaks, rubbing tubes and various parts coming loose or falling off...all
caused by "maitenance".

Mike
MU-2

"Peter Duniho" wrote in message
...
"Mike Rapoport" wrote in message
hlink.net...
You are probably more likely to have an engine failure from maitenance
than
from lack of maitenance.

Cute. But not really all that true, IMHO.

It depends on over how long a period of time you're talking about. If you
mean the instant after some maintenance is done, well sure...it's true
(but
obviously so, and not interestingly so). But if you look at the same
question over 2000 hours of operation or one or two decades, I suspect
that
lack of maintenance will show up as much more of an issue. The lack of
oil
changes alone are likely to be a major problem, never mind the myriad of
fixable problems that would normally be detected during routine
maintenance.

Pete

"Mike Rapoport" wrote in message
link.net...
[...] I have seen and heard of too many oil leaks, fuel
leaks, rubbing tubes and various parts coming loose or falling off...all
caused by "maitenance".

Well, granted, the engines on your plane require a much more specialized
maintenance crew than the one Lycoming on mine. But in spite of the very
real possibility of human error during maintenance, as far as I know more
engine failures are prevented by maintenance than are caused by it. I would
be very surprised if you could find statistics to the contrary.

Pete

Captain Wubba opined on engine failures snipped

One partial, a bad mag, on a twin in 1400 hours.


-ash
for assistance dial MYCROFTXXX

2500 hours. No failures where there was fuel in the tanks.
--
Gene Seibel
Hangar 131 - http://pad39a.com/gene/plane.html
Because I fly, I envy no one.

"Tom S." wrote in message news:...

"Mike Rapoport" wrote in message
link.net...

http://www.ntsb.gov/NTSB/brief.asp?e...12X20796&key=1

In sum...

"The National Transportation Safety Board determines the probable cause(s)
of this incident as follows:

The failure of a number one cylinder connecting rod bolt due to
under-torquing during engine major overhaul. "

On 24 Nov 2003 11:31:57 -0800, (Captain Wubba)
wrote:



So I'd like to find out if anyone has done any objective analysis of
certificated, piston-engine failure rates in light airplanes. I have
seen all kinds of 'guesses', but little in the way of objective facts.


There are variations depending on the engine and aircraft. Whether these
are significant is unknown, as the universe is too small to afford
significance to the statistics.

Last year, in the March and June issues (2002) Aviation Consumer published
studies on accidents in light and heavy single engine a/c of the type most
of us here fly.

The total accident rate from all causes was on the order of 3.8/100,000 hrs
and the fatal accident rate from all causes was on the order of 1.1/100,000
hrs.

Engine failures (NOT including fuel exhaustion) comprised about 21% of the
accidents so, since fatal accidents are likely all reported to the NTSB, I
think one could assume a fatal engine failure accident rate on the order of
1/500,000 hrs in this group of aircraft.




Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

750 hrs here (OK, 250 of them in gliders). One impending failure due
to broken shaft seal on the crankcase. The engine did not show oil
pressure any more, but I made it back to the airport with the engine
still running at near idle. It happened on the climbout, about 3000
AGL.

Tobias

(Captain Wubba) writes:

So what is it? If the engine-failure rate is one failure for every
50,000 flight hours, I'll feel much less reticent about night/IFR
single-engine flying than if it is one in 10,000 hours. Anybody have
any facts or hard data, or have any idea where I might be able to
track some down?

Don't forget that you're safest with a single-cylinder engine. If
you have a six-cylinder, you're *six* times as likely to have a
failure.

....or at least that's what I've learned from some of the geniuses
who talk about twins vs. singles.

--kyler