Talk me into a kiwi prop.

[GHA]

How many miles do you do per year. What is the speed increase, e.g 2,000 * 0.1 = 200 at 5kn = 40 hours or 20,000 * 0.1 at 5kn = 400 hours.

You will be able to work out when it becomes cost effective.

Impossible question could be between zero and 10,000

One possible benefit of the kiwi might be the option of altering the pitch, so on an offshore trip set it a bit higher for lower engine revs, the engine I will only be used when the sea is be oily flat.

Though just keeping the boat moving in light airs offshore is a main area where help would be welcome.

 

[Sybarite]

J'´

Impossible question could be between zero and 10,000

One possible benefit of the kiwi might be the option of altering the pitch, so on an offshore trip set it a bit higher for lower engine revs, the engine I will only be used when the sea is be oily flat.

Though just keeping the boat moving in light airs offshore is a main area where help would be welcome.

I have no experience of them but I am wondering if they make a significant difference on a long-keeled yacht.

 

[Kwik Decision]

So how much is a featherstream? Can't find a price on the web.

I Paid £1344 (inc VAT and delivery) for a 16" 3 blade featherstream for a 1" shaft, this time last year. It was bought through TS Marine, as they were fitting a new engine, but the price was +/- a pound the same as Darglow had quoted me at the boatshow.

Very happy with it.

 

[tri39]

I'm very pleased with my competitively priced Kiwi prop. And the Delrin blades do sem to be strong enough.
Reverse is a revelation in power. And sailing speed in light airs improved by the streaming "fins".
However you definitely need a lower gear (higher ratio) in reverse and more than 20Hp or the engine may stall. It helps to increase the idling revs.
But looking at your pic you're going to have to increase that aperture quite a bit to create enough clearance. And I suspect the acquired efficiencies
may not be so great in a long keeled yacht. One thing to bear in mind is that the Kiwi aligns with the water flow whatever the angle of the shaft,
whereas a lot of folders/featherers align only with shaft. So the more angled the shaft, the greater the Kiwi benefit. It must be kept clean and greased.
I find I still have to lock my shaft in fwds to prevent spinning.