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Date: Fri, 08 Apr 2005 20:06:19 -0400
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From: "Robert R Pastusek" <rpastusek@htii.com>
Subject: Engine Failure
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Dom Crain wrote:

<<Further, it seems to me that in the event of an engine failure in
  flight, the first thing after all the standard checks is to get the prop
  into full coarse, which we all know improves the glide ratio
  considerably.>>

Hmmm, with an engine failure in flight (depending on it's nature) it's
unlikely that you'll have the oil pressure required to run the prop to
coarse pitch (unless you have an accumulator or the failure allows the prop
to windmill). It is likely that you'll just have to take whatever pitch it
goes to when that happens. I understand that when oil pressure is lost, some
props go flat, some go coarse to a pre-set mechanical limit. But without oil
pressure, I don't think you'll do the chosing.
Dan Schaefer

Dan & Dom,

I broke a timing gear some years ago in my Cherokee 235 while eastbound near
Winslow, AZ--big Continental; constant speed prop. The engine stopped
producing power immediately but sounded like it was going to totally destroy
itself, so I raised the nose until the prop stopped, then back to best glide
down to a successful landing at the Winslow, AZ airport. My first reaction
when the engine stopped was that we were too far away to make the
field--based on many practice glides to a landing with the engine at idle.
We actually arrived over the field with sufficient altitude to maneuver and
land in the middle of the runway. I thought about this a lot during the time
the engine was being repaired, and ran some personal tests after the plane
was back flying. Findings:

-Stopping the prop approximately doubled the glide range for that airplane
when lightly loaded (Could never get my wife or friends to go practice that
manuever with me after their first experience).

-Coarse pitch improved the glide distance by about 30% over the standard
cruise pitch, but not nearly so much as stopping the prop.

-Stopping the prop (mixture in idle cut off) required that I slow to very
close to the stall speed with the prop control in "cruise" setting

-Getting the prop to start windmilling again after it was stopped required
that I push the nose over to well into the yellow arc (although a momentary
blip on the starter would start it windmilling again from any reasonable
glide speed)

Although I'd been told some of these things during my early flight training
years, I'd never actually shut the engine down in flight. The results were
significantly different than what I'd practiced with "simulated loss of
power."  I'm a lot more comfortable about doing this now, and intend to run
these tests on my Lancair after I'm comfortable with landing it power
off--just in case...

I didn't include information about specific performance numbers here because
I suspect every airplane/configuration will provide different results, and
my tests were not done with the rigor needed to specify the actual glide
ratios, airspeeds, etc. Even so, it's a worthwhile exercise to give you
valuable and useful knowledge--especially considering that a clean Lancair
should be able to go many miles with an engine loss at altitude.

Bob P

PS: There are some failures (i.e. loss of engine oil) that would cause you
to lose control of the prop, but for most engine failure modes, including
fuel starvation, you should be able to control it as long as the engine is
turning over. Course pitch is the right first step; I'd consider stopping
the prop as soon as you decide it's not going to restart. All this presumes
you have enough altitude/time to reflect, and don't forget to fly the
airplane while going through these steps!