Very interesting. I worked on Tugs forty years ago and twin screws were the Gold Standard for maneuverability for a long time even then. This beats the hell out of the rear mounted screws. If you ever want to know what expensive is, try having to call a diver in on a weekend to cut tow rope out of your propellers.
Looks pretty in deep water fjords, although lots of moving parts exposed to salt water.
As I recall, the NY harbor was rather notorious for sediment build-ups at wharfs. Even with a guard, things could get ugly if the vessel encountered the bottom.
I remember seeing my first jet boat early sixties. The lakes where I was raised had a lot of sand. I guess the sand ate up the pumps or something. They didn't last long in the Adirondacks. For a couple years they were around and then gone. Ha, they put out a big rooster tail.
Worked at a marina near Mpls. years ago. The "bowl" type pumps, Berkeley and Jacuzzi, are basically centrifugal fans. They depend upon a "Wear Ring" on the outer circumference. We made big money replacing those rings on Holiday weekends. I built a nice Hamilton pump into my boat. Since it is a turbine style axial flow, I frequently pumped mud, silt or sand through it with no problem in marshy water areas I needed to get into.
Very interesting.
ReplyDeleteI worked on Tugs forty years ago and twin screws were the Gold Standard for maneuverability for a long time even then.
This beats the hell out of the rear mounted screws.
If you ever want to know what expensive is, try having to call a diver in on a weekend to cut tow rope out of your propellers.
AGREE wholeheartedly.
DeleteListening to that will suck your brain out.
ReplyDeleteI aint no engineer but aint thet the same concept as a paddle wheel?
ReplyDeleteI was thinking of underwater, horizontal, variable displacement Pelton wheels.
DeleteOr a helicopter transmission. Weirdly interesting.
DeleteNeat idea, but you're going to need a dock with lots of depth capacity, especially if it's on a platform supply vessel.
ReplyDeleteLooks pretty in deep water fjords, although lots of moving parts exposed to salt water.
ReplyDeleteAs I recall, the NY harbor was rather notorious for sediment build-ups at wharfs. Even with a guard, things could get ugly if the vessel encountered the bottom.
I remember seeing my first jet boat early sixties. The lakes where I was raised had a lot of sand. I guess the sand ate up the pumps or something. They didn't last long in the Adirondacks. For a couple years they were around and then gone. Ha, they put out a big rooster tail.
DeleteWe'll never run out of the most important resource: human ingenuity.
ReplyDeleteI do not know the cost per propeller, BUT this presentation IS AWESOME. If their devices are as good....WELL?
ReplyDeleteWorked at a marina near Mpls. years ago. The "bowl" type pumps, Berkeley and Jacuzzi, are basically centrifugal fans. They depend upon a "Wear Ring" on the outer circumference. We made big money replacing those rings on Holiday weekends. I built a nice Hamilton pump into my boat. Since it is a turbine style axial flow, I frequently pumped mud, silt or sand through it with no problem in marshy water areas I needed to get into.
ReplyDelete