From: venky@thelonious.bellcore.com (G A Venkatesh)
Subject: Re: Subaru Power?
Reply-To: venky@thelonious.bellcore.com (G A Venkatesh)
Organization: Bellcore, Morristown NJ
Date: Wed, 7 Oct 92 15:29:17 GMT

In article <1atcl2INNb7e@usenet.INS.CWRU.Edu> ch491@cleveland.Freenet.Edu (Pj Pisczak) writes:
>
>Not wanting to ignite the aircraft vs auto engine controversey I
>would like to add the following observations.

Let me start off by saying that this controversy is *good* and needs to be
explored more fully. A lot of us are interested in auto-conversions for
aviation use and would like to get as much information about it as possible.

> ... a very informative post deleted ...

>	My apologies to the NET for the length of time huge
>topic.  I obviously favor the engine, but not without some con-
>cerns.  

Apologize??? This is what this group is for. We *need* more posts like that.

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.

The things that bother me the most about auto-engines at the moment:

1. Single ignition system that is tied to the electrical system.

2. Timing belts

3. Water pumps (for water cooled engines)

4. Repair and overhaul facilities (Unless I personally know the abilities of
   an auto-mechanic, I am not going to trust the engine to that person. The 
   concept of tight tolerances is very foreign to an average auto-mechanic. 
   The overhaul may be cheap but not reliable)

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. 

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

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.

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
From: jstrom@hpcc01.corp.hp.com (Johan Strombom)
Date: Wed, 7 Oct 1992 16:23:27 GMT
Subject: Re: Para-plane
Organization: the HP Corporate notes server