My wife getting scared

BTW, did your 540 overhaul only cost $20k? That sounds like a steal!

Well, that was 5 years ago now, so figure 20% higher today.

And, the guy is just a gem. He's fair, and incredibly knowledgable...
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

Jay Honeck wrote:
You may not agree, and maybe your mechanic doesn't agree ... but as said
in an earlier post, if you think about all the airplanes in flight
schools that are doing simulated engine failures far more frequently
than we would (some much more powerful than an 0-320 ... I can't
remember what engine you have), there would be many more engine problems
in rental/school airplanes than there are if there's nothing worse for
an engine than simulated engine-outs.

My mechanic -- a guy with over 40 years of experience as an IA, A&P,
grand champion home builder, and owner of an engine and prop shop --
says it this way:

The average privately owned GA aircraft is flown AT MOST once a week.
As a result, rust (from inactivity) is the #1 killer of the average,
privately owned GA engine. Many don't make TBO because of
inactivity.

Touch & goes are the #1 worst thing you can do to your engine. Flight
school planes do them all day long, but it's because they are flown
daily, sometimes 8 hours per day, and they therefore NEVER experience
the ravages of inactivity. Therefore, although it's STILL the worst
thing you can do, the engines often make it to TBO simply because they
are flown all day, every day.

Engine out practice is essentially the same engine management
procedure as a touch & go. Long periods of high power, followed by
suddenly low RPM, followed by a sudden application of power at the
end. Bad, bad, bad.

I don't believe the data supports this as being bad, bad, bad.

Matt

"Jay Honeck" wrote:

There is simply nothing
you can do to your engine (in normal use) that is worse than simulated
engine-out landings,

How so?

--
Dan
T-182T at BFM

Jay Honeck wrote:
Question: how often do you practice simulated engine failures over
places you aren't used to flying patterns?

Sadly, I have to admit that our fear of harming our engine has far
outweighed our fear of an engine-out landing. There is simply nothing
you can do to your engine (in normal use) that is worse than simulated
engine-out landings, so we do them very rarely.

I personally think that is a myth. I've read about shock cooling until
I'm blue in the face and I simply don't buy it. However, the main
reason is that my primary flight instructor, who is also an A&P and was
an airport manager for many years, always flew all of his airplanes on
power-off gliding approaches. He operated 2 C-150s, 1 C-172 and 2 C-182
for probably two decades and several other airplanes for the two
decades prior to when I met him.

He operated N38 for something like 45 years and flew scenic tours over
the PA Grand Canyon in his 182s and 172. These flights lasted 10-15
minutes and he glided power-off from pattern altitude to landing and
shut-down between runs. His airplanes were started, stopped and "shock
cooled" literally dozens of times every Saturday and Sunday. His 150s
trained students to also fly the way he flew (I'm one of them).

He never had a engine failure in these airplanes to my knowledge and
they routinely ran to TBO. He often groused how the FAA made him
rebuild a perfectly good engine just because he was a commercial operator!

So, I've seen scads of real-life experience that says that shock cooling
is just not real. The real part is people who don't practice engine-out
landings and then crumple an airplane botching the real thing.

Let the games begin! :-)

Matt

So, I've seen scads of real-life experience that says that shock cooling
is just not real. The real part is people who don't practice engine-out
landings and then crumple an airplane botching the real thing.

I don't believe shock cooling exists, either. Or, if it does, it's
fairly insignificant.

But I do believe that repeated and sudden applications of full power
are harder on an engine than steady-state operation. Touch & goes
and engine out practice require this type of engine operation.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

"Jay Honeck" wrote:


But I do believe that repeated and sudden applications of full power
are harder on an engine than steady-state operation.

But *why* do you believe it? Why is it the worst thing you can do to your
engine?

--
Dan
T-182T at BFM

On Tue, 2 Oct 2007 05:56:51 -0500, "Dan Luke"
wrote in
:


"Jay Honeck" wrote:


But I do believe that repeated and sudden applications of full power
are harder on an engine than steady-state operation.

But *why* do you believe it? Why is it the worst thing you can do to your
engine?

And why would a pilot use sudden movements of the controls? Aren't we
taught to be smooth?

I don't believe shock cooling exists, either. Or, if it does, it's
fairly insignificant.

Tell it to a towplane owner/operator :-)

Bartek

Jay Honeck wrote:
So, I've seen scads of real-life experience that says that shock cooling
is just not real. The real part is people who don't practice engine-out
landings and then crumple an airplane botching the real thing.

I don't believe shock cooling exists, either. Or, if it does, it's
fairly insignificant.

But I do believe that repeated and sudden applications of full power
are harder on an engine than steady-state operation. Touch & goes
and engine out practice require this type of engine operation.

Engines have vibration and resonances that vary with RPM. Running at a
constant RPM for long periods of time causes a certain wear pattern on
certain parts. Varying RPM over time induces different vibration an
part resonances and spreads the wear over different areas. This isn't a
bad, bad, bad thing.

Matt

Matt Whiting wrote:
Engines have vibration and resonances that vary with RPM. Running at a
constant RPM for long periods of time causes a certain wear pattern on
certain parts. Varying RPM over time induces different vibration an
part resonances and spreads the wear over different areas. This isn't a
bad, bad, bad thing.

My mechanic echoed this also. I was told even in cruise that it's a good
idea to vary the RPMs every 10 minutes or so.