Maybe this guy can build a carbon fiber bell housings for
us.
I think I will send him email and ask.

Paul Lamar

Paul, I wanted to say that I have mentioned this
before. At that time we seemed to agree that the
hazards that would be caused be fire might not be
acceptable. Otherwise why not make the housing,
gearcase, and engine mount/schertz beam out of
carbon? I have had many e-mail communications
with David Algie. He is a very knowledgeable
fabricator. He works for Team Green IRL team as
their chief fabricator. I really like his aircraft,
but I think his design is a bit too "hot" for my
piloting skills level. His work is excellent.
Bill Jepson

The fire hazard is a very good point. If the gear box drops
of from a fire you are in even more danger of crashing right
now.

Is the problem here FIRE or HEAT? You can get flame-retardant epoxies from a
number of sources that could be used as a skim coat on the outside of the
layup. A few coats of it would provide flame resistance for a specific length
of time, depending on the thickness of the coat and the specific epoxy selected.

It's not flame-PROOF, but then, neither is the average pusher firewall, so if
you could provide the same minutes of resistance as the Fibrefrax we pusher
guys use, well... Let's just say if my entire engine is about to drop off the
plane, I'm less concerned about the gearbox.

As far as why an engine mount or similar might not be made out of the same
material, I can think of a few good reasons. Making the joins with the same
strength as a weld is complex, because it's hard to get fabric to conform to
these angles. And the engineering of figuring out which way the fibers should
run is complex, too. There's a lot of engineering in how that's done - much
more than in a simple weld. I don't mean to trivialize the value of a good
weld, but compared to this it's a walk in the park.

Cost is another - 1" carbon-fiber tubing costs anywhere between $20-$30 PER
FOOT. You can wind your own, but that's hard too. The only way I could see
doing this is by gluing up cardboard tubes to build up a complete mockup, then
wind thread around the whole thing until it's got enough. It would take a heck
of a long time, would be hard to do right, and might not yield any cost
savings. It would be lighter, but maybe not even much there, either.

There are plenty of other uses for composites in an engine compartment but
most of the ones I can think of are things like in the intake system, airflow
for cooling, etc. Not because they're non-critical but simply because you get
a big bang (weight reduction) for the buck and they're easy to make.

Regards,
Chad

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