For your interest I would try to tell about my experiment with M/Y Maya.
The extension (X-drive) is now completed with assistance of a wellknowned designer.
The main reason for an additional engine is the speed limits on the European canals, max 10 or even 6 km/h (5,4 or 3,2knots). It´s not acceptable with hundred of hours on idling for the 6LYA-STP.
The bottom lines of the hull is extended about 3 feet and top of the swim platform about 4,5 feet. The powerline is a VP D2-40 with saildrive and Autostream feathering prop, the speed is 1-6+ knots.
The advantages are several as, safety redundancy for propulsion and steering, the floating level has approved in many ways, the steering is very good, especially in low speed and very much in reverse, with an extra controlled generator it replace my genset, the noise from that engine is almost zero (the only noise is from the control cables, motor and gearbox, its on my list). It´s fantastic to run a quiet boat!
The maximum speed has not been effected, it’s still +14 knots. I´m not missing the trimtabs.
Maya act well on raff sea, as we have here in Scandinavia, also in following sea with her dubble rudder and the S-drive (xtra pivot center) in the very end of the hull. Its easy to reach the prop from the swimladder to adjust the the pitch or just clean the prop.
I'm happy to tell that 96 holes has been closed in the aft of the hull, non facing the water left.
The X-drive is secured bolted to the hull and guite possible to replace back to the original swimplattform, but I wont.
Your question about the fuel consumption is less than half, in low speed. We pay about $8/gallon.
I dont expext this is a good investment but it was a piece of mind when I got retired. I'm very happy with her performance and we are looking forward to spend some time in the canals of Europe.
/boan
See clip on Youtube.
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