I need help finding a part I saw.

I know the title is vague but I didn't know how else to word the problem.

I was cruising boating sites and came across a picture of a delta wing shaped plate that mounts below the prop. It is claimed to provide some efficiency improvement. I am interested in the idea and want to learn more about the concept.

I have searched but I can not find the site again. Has anyone seen this part? Please post a link if you have it.

 

Assume an outboard??? Or I/O?

Well there's anti cav plates,and theres all sorts of hydrofoil plates on the market-good for the holeshot.

Not sure I'd use a foil on an outboard,who knows if the mounts could handle the extra load?

 

It is for huge ships. It is integrated into the lower part of the hull. It is a big triangle laying flat, point forward, directly below the prop I think the rear tips were bent up a bit. It is slightly wider than the prop.

 

Big ships? Be specific please so as not to waste others time.

Hit- Control H ,your browser will pull up your history. Look .

 

The article I saw is for container ships. I have searched every combination I can think of and no luck on Google. I have no history so no luck there. Usually I bookmark interesting things I want to go back and review but I didn't seem to bookmark this one.

I'm hoping one of the designers that frequents this forum will recognize what I am talking about and point me in the right direction.

 

You can check your browse history for the date you saw it even if you did not bookmark it.

 

There are devices mounted on ship rudders to straighten the prop flow to as some thrust .

Is this what you want?

FF

 

I've seen a couple delta wing designs on outboards. One mounts to the cavitation plate the other to the skeg below the prop. The upper one is supposed to reduce cavitation to help push a loaded dingy. I see the lower one on boats that frequent Fla and the Bahamas. I think it is more to protect manatees from the prop and the prop from the bottom. May also give some lift to help the boat plane. Have no idea where to purchase. Maybe check some cruising forums.

Oops, just noticed you were talking container ship....never mind.

 

Yes it is similar in shape to the delta wing add on for outboards. The difference is it lives below the prop and the one I saw is maybe 20 feet wide. It extends from the base on the canoe stern shape to the rudder where it acts as the lower support for the rudder.


I want to look at the concept and see if it may be able to serve triple purpose on a catamaran. If it helps prop efficiency that is a bonus but it looks to me like a great way to reduce the hobby horse pitching motion. In addition it gives the prop and rudder total protection from fouling and impact.

I don't have any history in my browser, I always set my browsers for no history or cookies.

 

When I read your post the first thing that came to mind is what we call a Beavertail. On commercial gillnetters it's major purpose is to protect the prop from being fouled by nets, but it can also be designed to provide additional lift to the stern. When they're built correctly they also add extra support for the rudder shoe allowing a grounded vessel to recover from the incident with little or no harm.

Although I've never seen one shaped like a foil I see no reason why it couldn't be done.

One word of caution...adding lift to the stern can create a bow down attitude.

MM