Lateral motion by twin waterjets

[telrunya]

Hi all

I'm interested in using twin waterjets and I'm curious on how it provides a lateral thrust to the boat without yawing.

Can anyone explain what's the combination of machineries (i.e. nozzle, bucket, throttle) that produces a lateral thrust to the boat?

Thank you!

[BMcF]

It's a simple vector addition. Typically, both jet units are turned outward/outboard and one placed in forward and one in reverse. The fore-aft thrust vectors cancel and you are left with only the residual combination of side thrust vectors, which side direction depending simply on which unit is in the forward bucket position and which in reverse.

I had a simple diagram somewhere that shows what I described above. I'll try to find it.

[CDK]

The large catamaran ferries here use such a system.
Nozzles and buckets are articulated by hydraulics, but the actual controls are electronic: Two joysticks, each controlling one jet and the corresponding engine, plus a lock/unlock switch for normal navigation and docking.

[powerabout]

not great though as many of the large high speed ferrys have smacked the dock
For their windage they need something more