If someone have comments about this design they are free to let me know.


Jean Prudhomme


Jean,
 Since you asked . . . is there some reason you didn't choose a push-pull
design like the Rutan Defiant?  It has four significant  advantages over
the design you are contemplating:


 - Centerline thrust is maintained in an engine-out situation.
   This is a biggie.

 - Lighter weight (due to the elimination of the right-angle
   drive and the lengthy drive shafts)

 - More power to the props (again, by eliminating the
   right angle turn for both engines)

 - Simplicity: You'd be installing two engines in ways that
   are well understood.   No unproven configurations, etc.

Now, I'm all for innovation and trying new things if the goal is to achieve
something better than what we have at present.  I'm having trouble seeing
the advantages of the twin-pusher design unless it is aesthetics or maybe
a hoped-for improvement in aerodynamic performance (by getting the props
into cleaner air) I'd guess any improvements in aerodynamic performance
would be minor compared to a Defiant-type layout.  Yes, the props are in
cleaner air, but there's more frontal area (due to the transmission/hub
nacelles on the wings).  And, all the weight increases described before
also have an aerodynamic cost--in induced drag at all speeds.

This is just my opinion.  I'm glad we live in a world where
individuals can try new things . . .

Mark Waldron