OK I plead ignorance here but bear with me.
Rusty was talking about using two single rotor engines as a means of
redundancy.  Well that triggered a memory (of the 2 or 3 I have left)
from something David Atkins said to me once. It was, "a 13B is really
two separate engines connected to a common drive shaft". I'm sure he
was simplifying and only trying to help me get the picture. But isn't
this somewhat true?

Would it be possible to treat a 13B as 2 singles that happened to
share a common side housing? What I'm wondering is, can you use 2
carburetors, 2 fuel pumps, 2 ignition systems & CAS's on a single 13B
- each rotor independently serviced - and still have reasonable
performance (i.e. HP)? You would still have a common oil and water
cooling system - but hey that eliminates the EFI, ECU, and potentially
your electrical system as single points of engine failure.

Just a thought...Fire away...

Joe Hull (still dreaming of starting my 13B - after the nightmare of
painting is over!) Bellevue (Seattle), Washington Cozy MkIV #991
(working on Engine & Electrical & Finishing)
http://www.maddyhome.com/canardpages/pages/JoeHull/index.html