fabio buzzi drive concept

[yipster]

any modern, or old fashioned hydrodynamicist / drive experts dare try to explain fabio buzzi's newest concept masterpiece?
looks good, rudder before controlabe counter rotating surface props??? like it but eh.. sure want to learn more on this one..

[Yellowjacket]

Not sure, but I'm thinking it's just easier to put the rudder ahead of the prop rather than figuring a way to get it around the prop to be behind it. Outboards have had a skeg ahead of the pro for probalby 100 years now and we look at that and think that is normal. I've seen some other drives with a small skeg ahead of the prop, but they were, like outboards, always aligned with the prop. The shaft here is fixed and the rudders work ahead of the props.

Maybe it doesn't matter if you are going really fast.

[thudpucker]

It looks like he's got the "Turbine" idea in mind.
Two props going opposite direction, with the blades passing each other as a Rotor and Stater.
Since Water don't compress, he probably thinks he get's twice the 'push' at the point those two prop blades pass each other.

The Rudders in front of the prop are probably esthetics.

You'd sure want a Skeg to protect all that expensive machinery if you were going to jump a log etc.
I'm just guessing. I don't know enough to do more than guess!

[powerabout]

looks like a copy of the duoprop sterndrive concept
from 25 years ago wasnt it??
Nevertheless great work to add duo prop to a surface drive

[IMP-ish]

Very cool post yipster.
Zooming in, the way the prop blades attach to the hub, does the TBS drive have variable or even controllable pitch props going on there too?

[yipster]

thx for the speculations, could be that are not controlable pitch props but interchangeble blades
the rudders however also protect the props a bit and from this designer i wouldnt expect safety over speed
i never run a surface drive but i've been asking arneson before on surface drive propwalk and dual drives, was told the vertical force was much higher
this way however no propwalk and counter rotating props -as i noticed 20 years ago- give more thrust
daring concept and only imagining how that would do on a surface drive

[MechaNik]

Very interesting. I would assume this is more to get better efficiency from smaller propellers without using large reduction box.
Most yachts with three engines are already struggling for sufficient transom width to swing three surface piercing propellers, this could be a way around that.
Interesting they would have anything in front of the prop, most suppliers are insistent that the water flow is best as possible into the flow, no skin fittings etc.
What if they are not rudders but an attempt to focus the fluid stream at some point of operation?

[PetterM]

There is was been quite a few patents published relating to this drive over last years.
According to Mr Buzzi its designed for lower speeds than the rest of the rest of the trimax range of drives.