Snip>
They frequently say "we can't make
money on that" for various reasons. That is not the case with
the turbofan makers. They can make big money on a better turbofan.
The profits are there for them and the airlines.

Wrathall Mark wrote:

GE spent millions developing the GE36 unducted fan engine. What they came
away with was a production ready design which gave about 25% better fuel
economy but increased noise. They decided with the current low and stable
oil prices, coupled to the growing noise restrictions, it was unmarketable.
It did give them the Composite fan experience required to build a 123"
carbon fiber fan for the GE90. As paul said, this is how these companies
work, it all comes down to risk management.

All of the companies which are trying to jump into the certified engine
market (Orenda,Zoche,Dynacam) will probably fail, simply because the market
is too small and all aircraft are designed around aircooled flat
fours/Sixes. This has been Rotax's success, get a huge base of installed
engines (homebuilts and motorgliders + snow mobiles) so you can get the cost
advantages of volume prduction and designers will start designing airframes
optimised for your engine (even if technically they aren't the best
solution).

The 13b is a great engine and offers homebuilders an excellent alternative,
but if you want one in tommorrows certified composite Cessna there are a few
prerequsites:

1. There will need to be a standard configuration which has shown the world
that the idea works (something Paul is pushing). Unfortunatly everyone has
their own standard installation. The VW conversion reached a kind of
standard, and became a certified motorglider engine (Limbach) so it is
possible. The 13b with Tracy or Ross's PRSU, Tracy's EFI system, and a
street port seems to be a sort of standard here.

2. A company must take the risk. Jabaru is a good example, it seems to the
customer to be a manufacturing company, but behind the scene lots is farmed
out. The ideal for the aviation 13b would be a company which assembles and
markets the engine sourcing parts from Mazda, RWS, etc. The need for FAA
certifed EFI fuel system components raises its ugly head.

3. Some company will have to manufacturer every part to an FAA PMA to
satisfy the paperwork requirements of certified aircraft engines, and the
only company in a position to do that is Mazda. For them it is just a
paperwork change. Tracy, Have you ever given thought to this for your parts?
Do you know if the the Mazda engineering department even knows about this
Newsgroup?

Mark Wrathall

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