Hi Paul

When one buys an aircraft engine , first and foremost one is hopefully
buying reliabilty and power secondarily.

These rotary engines are automobile engines, designed for autos. Is this an
risky compromise withrespect to the reliability issue.

Put another way, if you were designing an aircraft rotary engine from the
ground up, how would it vary from the 13b or the 20b for that matter.

I really like this rotary concept ; I'm just very cautious about relatively
untested engines.

Thanks

Bill

The only thing I would do differently is make the endhousing the same way
the rotor housings are made. Aluminum with a cast in steel wear surface.
This would cut a bit of the weight. 

These installation problems we are seeing now  have nothing
to do with the basic engine. We will get beyond these installation problems
any year now :) You must realize a certified aircraft engine 
installation has had a 100 years to work out the details. 

The rotary is way over designed for automotive use and is in no way comparable
to an automotive piston engine as far as duty cycle is concerned. 
It is an ideal aircraft engine. Simple, robust  and with no exhaust valves.
Potentially it is twice as reliable as any piston engine. I would not
be a bit surprised if the TBO worked out to well over 3000 hours.

Many of the complex systems Tracy has developed such as EFI and electronic
ignition are slowly making their way to the aircraft piston engine.
They too will go through some of the same teething problems
we have already solved. So in a way things are converging.

In this particular case a welder was employed that apparently did
not have any internal combustion engine exhaust system fabrication 
experience. I think the second factor was PowerSport was not aware 
of the proper leaning of the engine. It is not necessary to cruise 
the engine at 1700 F EGT. The engine will cruise fine at a leaner
setting and which will result in a cooler exhaust. Around 1450 F EGT.
It is a question of reprogramming the EFI computer. Power Sport
does not use Tracy's computer or they would have known about this.

The new RX8 engine is already showing a much cooler exhaust with
a much more gradual opening of the side exhaust ports. This will
probably eliminate the supersonic shock waves that play havoc
with the current exhaust systems.

Paul Lamar
 
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