From: enns@waterloo.hp.com (Roger Enns)
Subject: Re: Subaru Power?
Date: Wed, 7 Oct 1992 16:26:56 GMT
Organization: HP Panacom Div Waterloo ON Canada
X-Newsreader: TIN [version 1.1.4 PL6]

>I think auto-engines (or at least auto-engine manufacturers) are going to 
>influence general aviation to a great extent in this decade. The use of
>"auto-engines" can be separated into several levels of "risk":
>
>1. Taking a stock auto-engine (new or salvaged) and designing the mounts,
>cowlings, exhausts, cooling systems, etc. to fit your homebuilt.
>
>2. Using professionals to reconfigure the engine for you and to supply the 
>reduction units, etc.
>
>3. Having a kit/plan designer to support an auto-engine conversion having 
>tested the conversion in a prototype.
>
>4. Having an auto-manufacturer make an aviation version of their auto-engine.
>
>Many of the objections to use of auto-engines and failure statistics apply to
>examples from types 1 and 2. 
>
>I would be more comfortable with auto-engines when 3 and 4 above start to
>happen on a regular basis. Talking to the kit manufacturers, auto engine options
>rank very high on their list of most frequently asked questions from customers.
>Price seems to be the major motivation and to a certain extent the 
>availability of leaded fuels in the future.

I feel that point '3' above will not happen until enough people
have survived the '1' and '2' stage.  It would be foolhardy for
an aircraft designer to base his design around an engine not yet
recognized or accepted as an alternative.  The Sept. issue of
Kitplanes shows a new design called the Stiletto.  It is designed
around the Subaru EA81 engine.  This engine is rapidly gaining
popularity as an auto conversion, but this aircraft is the first
design I know of that is based on that engine.  If the engine
proves to not be a reliable and economical choice, the design is
in trouble.

>I would definitely wait for either kit manufacturers to support one are
>more auto-engine conversions which would lead to well-known overhaul centers 
>for aircraft use (similar to the support for two-cycle engines) or for a 
>company to develop and stand behind their engines. I am eager to see what 
>Toyota may come up with. 

By the time Toyota is finished its R&D work, the engine may end
up costing as much as similar certified engines of today.  I
would hope that other factors would improve, however.

>Does anyone know if the Porsche engines used in Mooney's for a while are 
>available in the market?

The last I had heard, the Porsche aircraft engine project had
been dropped.  The cost of the engine was comparable with its
competitors, but fuel efficiency and weight were very similar.

>The modified Lycoming on the Berkut has an interesting design. One set of
>spark-plugs to each cylinder is controlled by a conventional magneto while the
>other set is controlled by electronic ignition.

There are numerous suppliers of the 'mag-replacement' electronic
ignition systems for aircraft engines.  Claus Savier (sp?), the
Varieze speed demon, has a well-respected system for sale.  See
the back of Kitplanes/Sport Aviation.

>Will modern auto-engines develop into full-fledged aviation engines or will the
>certified aviation engines adopt the advances in engine technology with
>price reductions from the current levels?
>
>venky
>
The auto-engine conversions will only take over if professional
companies with many hundreds of hours of test time on their
engines market a price-competetive complete package.  As soon as
the average homebuilder is asked to come up with his own back-up
ignition system, mixture control, charging system, cooling
system... etc, there is too much room for error.

My 0.02 cents Canadian (0.015 cents US)
--
Roger Enns (enns@waterloo.hp.com) Panacom Automation Division, HP
C-GIIV Dragonfly, 1979 RX7 13B, 1985 Colt