Oh those CERTIFIED plane engines !!!!!!!!!!!!!!!!!

RapidRonnie wrote:

Bottom line is that if you use an auto engine made in the millions you
can research the failure rate, particularly if you pick an engine used
in motorsports run to destruction you can see where they fail first. I
would pay a premium, a big premium, to be able to fly a small block
Chevy in terms of a bigger airframe than you otherwise would, just for
that huge knowledge base.


Gently disagree, Ron.

The reason is that the prop loads are far different from anything you'll
see on the race track.

Apples and oranges again...

Richard

"Richard Lamb" wrote in message
ink.net...
RapidRonnie wrote:

Bottom line is that if you use an auto engine made in the millions you
can research the failure rate, particularly if you pick an engine used
in motorsports run to destruction you can see where they fail first. I
would pay a premium, a big premium, to be able to fly a small block
Chevy in terms of a bigger airframe than you otherwise would, just for
that huge knowledge base.


Gently disagree, Ron.

The reason is that the prop loads are far different from anything you'll
see on the race track.

Apples and oranges again...

Richard

Perhaps, but it is entirely possible to use a Geschwender chain drive or one
of several belt drives that have all been around for 30 years themselves.
Their job is to match the prop to the crank. The loads on the crank can be
reduced to nothing but torque, and the torsional vibration issues dealt
with. The engineering has been done, and it works.

The NorthWest Aero belt drive http://www.northwest-aero.com/ as an example,
was derived (I think) from the Blanton PSRU that has been around since the
1960's. Many Ford 3.8 and GM 4.3l V6's and 350 V8's have been run many
thousands of hours. Improvements have been made over the years (better
belts, different bearings, easier adjustments.

If there has been a failure of a properly maintained one in the last few
years, I'd love to hear about it.

Failures of auto conversions tend to be stupid stuff anyway. This guy
http://www.epi-eng.com/Prop-SudnStop.htm somehow left one of those blue
paper towels inside his cowling. It got sucked through the turbocharger,
shredded, and completely clogged the air filter. Bad...but not the fault of
the fact that it was an auto engine.

The vast majority of auto conversions use a PSRU to transmit the power
from the motor to the prop. Ron has pointed that out nicely. You can
see mine up close by going to my website and clicking on pics. Quick,
simple and a picture is worth a thousand words.


Ben
www.haaspowerair.com

Richard Lamb wrote:
RapidRonnie wrote:

Bottom line is that if you use an auto engine made in the millions you
can research the failure rate, particularly if you pick an engine used
in motorsports run to destruction you can see where they fail first. I
would pay a premium, a big premium, to be able to fly a small block
Chevy in terms of a bigger airframe than you otherwise would, just for
that huge knowledge base.


Gently disagree, Ron.

The reason is that the prop loads are far different from anything you'll
see on the race track.


If I may be forgiven (or not) for reading about the Corvair crank
failures with rectal vision, they should not have surprised anyone.

I have never heard of anyone breaking the crankshat in their family
car,
that includes VWs. That tells me that auto manufacturers in general
and VW in particular have sucessfully designed their cranks to last
indefinately under nominal and even somewhat more adverse than
nominal conditions.

One supposes, however, that auto manufacturers do not make the
crank a whole lot stronger than needed to achieve that result.
A part that lasts indefinately is not improved by making it last
longer than indefinately when doing so would add weight which,
especially to a high RPM moving part, is generally a bad idea.

There are a lot of VW powered airplanes, and it is not uncommon
for the crankshaft to break in those.

If we make the unremarkable assumption that GM did not over-
design their Corvair crankshats any more than VW did theirs then
the Corvair crankshaft failures are quite predictable.

It is highly unlikely that any auto manufacturer is going to put
a crankshaft that is a whole lot stronger than needed into a
standard engine, don't you think?

--

FF

stol wrote:
For all you guys and gals building a homebuilt plane DO NOT use a auto
engine conversion or any other option that is not FAA certified, Ya see
the feds and Lycoming have a lock on the market providing "quality and
time tested powerplants". Let's see now. it all started a few years
back when Lycoming had a brain fart and decided they knew more about
crankshafts then god, so they redid them, with the FAA's blessing of
course. Ya know the feds demand strict safety testing and "high"
quality control over certified parts. Well, that batch of hundreds had
several break and kill a few innocent souls, So they recalled them and
redesigned the problem out of them and in the meantime kept hundrends
of planes grounded for months while they " patched" the issue. They
introduced a "New and Improved" crank that would cure all their issues.
Well, those broke at a alarming rate and killed 14 innocent souls. All
the while with the feds watching this all unfold. Lycoming then tried
to sue the forging company that stamped out the cranks that THEY speced
the design for. Well, that didn't fly either.


So here comes round number three. Too bad they don't have the three
strike rule in aviation..

http://www.lycoming.textron.com/supp...tins/SB569.pdf

Ben
www.haaspowerair.com

ya, I am the bad guy trying to get ol Barnyard Blob to wake up. G

I've got a reason for delaying any decision regarding a kit or the
engine. TBOs asice, theres the basic reliability factor. I'm not
comnfortable with the current options based on the remote areas I would
plan to go.

i know there aren't that many engine failures, but I have a magnetic
draw to Murphy. He'd certainly be my passenger running somewhere
between Calgary and Anchorage.