X-Mozilla-Keys:                                                                                 
Sam Frasier wrote:

Hi Tracy,

I reciently read a short article in Sport Aviation about a "smartplug"
which needs no ignition system to support its operation.  I respect your
efforts in making rotory aviation a practical chioce and wanted to tell
what I've learned.

The article states that spark is supported by a catylist and that it uses

a

precombution chamber, and once the catylist is heated the plug is a stand
alone system.

I "guessed" that they were using the "precombution chamber" as their

timing

device (using the engine compression to force the air-fuel mixture up to
the catylist at a precise point).  So I beat the guts out of a stock

plug,

did some rough number crunching, and built one.  I used a model airplane
gloplug as my igniter.  I put it in a Honda engine that I had handy and
vuala!  It worked! The whole thing, from concept to running engine, was
about two hours.

I then went to the University of Idaho (which is here in Moscow, where I
live) and spoke with one of my old proffs about this.  He and one of his
grad-students have been working with the inventor, who is located in
Sandpoint, a few miles north of here. While I see limits in that your
timing is fixed, here is the cool stuff.

The inventor, Tom Cherry, drives a rotory powered mustang and uses this
plug as his ignition source.

The pre-combustion chamber produces an jet of flame which makes for a

more

complete fuel burn and also makes it possible to run deisel in a gasoline
engine.  Thats right!  And their using the stock CARBURETOR, with no

change

in jetting.  The deisel has proven to make slightly better power than gas
in the same engine.

The problems are that gloplugs need continous power to remain hot enough

to

ignight the fuel and they do not last very long.  The catylist, once
heated, needs only the combustion process to remain hot, but until
receintly they had not found a material that had an adaquate life.

THIS IS NOT SNAKE OIL!!!

Deisel powered rotory? Hmm I wonder if you would need oil to lubricate

the

seals anymore.

If you would like more info, let me know.  I have patent#, names, and

phone

numbers.

F Y I

Sam Frasier

The big question is; how does it know when to fire?
Timeing in a rotary engine is critical.
Best timeing in an aircraft is also a function of altitude.
Color me skeptical.

Paul Lamar
 
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