"Denny" wrote in message
...
Well, my reference is 6 decades of banging around behind aircraft
engines of various makes, Lyc, Cont, P&W, Franklin, etc... In that
time period I have had one sudden engine failure, a Continental on T-
Craft that blew a jug landed in a field, fixed it, flew it out..
Also in that time period I have had at least a dozen or more, but
who's counting sudden engine failures in cars/trucks/boats...
Now for you statisticians, yes I have many more hours behind auto/boat
engines than aircraft... But if the auto engines had been maintained
to the standard of aircraft engines likely I would have had few or no
failures...

So, for me the issue is reliability... Based on my experience I will
stay with certified aircraft engines for my airplanes...
I do not claim that an auto engine is intrinsically less reliable when
used in an aircraft... But I can certainly tell from being around
experimental aircraft since the early 1960's that aircraft engine
installations are more reliable than auto conversion installations...
The major factor here is the quality of the engineering in the
installation/conversion...

You can argue that the aircraft engine is more reliable only because
of standardization of parts, installation, etc. and from continued
refinements from analyzing the failures that have occured - which is
why we have dual magneto's, etc...
And you can hypothesize that if Toyota were to get into the piston
airplane engine market that their level of engineering expertise and
the financial resources they can bring to bear would result in a
reliable auto engine conversion equaling any Lyc, etc... And you
would be right... And the cost to buy, install, and maintain, that
certified auto engine will not be one penny less than a certified
Lycosaurus - see the Mooney / Porsche if you don't believe it...

But that generalized certified auto conversion hasn't happened yet...
And the vast majority of shade tree mechanic installations in aircraft
have been less than world class in quality and reliability... So,
being a betting man every time I strap on a plane I will bet with
the odds not against...

denny

That is absolutely the best summation that I have read in a long time!

Peter