A major improvement in efficiency? the new 'Sharrow propellor'

Scarron said:
Is this a useful new engineering development or snake oil?

https://www.boattest.com/review/sharrow-engineering/3986

It certainly looks interesting although I would want to see a comparison with duoprops with a total of 6 blades as a lot of the claimed improvements are also claimed by Volvo for their duo-prop systems.
Click to expand...

Would be interesting to read but the article seems to be largely hidden behind an authentication wall.
 
vas said:
not much to read J,

http://www.sharrowengineering.com/the-propeller/

dunno, could be interesting, could be snake oil. Need an example and some test data which we probably wont get...

V.
Click to expand...

If you scroll down on the linked site, there is fairly significant discussion and testing data to be seen, all without registration. The design of the website makes it seem there is little on offer but it is there albeit in a small window. At least one of the test conculsions is unfairly presented imo, and the issue is obvious. That minor presentation issue (author at fault) aside, it looks interesting.
 
Don't know whether it's 'best thing since sliced bread' or 'snake oil' but it certainly looks cool!
 
Scarron said:
Is this a useful new engineering development or snake oil?

https://www.boattest.com/review/sharrow-engineering/3986

It certainly looks interesting although I would want to see a comparison with duoprops with a total of 6 blades as a lot of the claimed improvements are also claimed by Volvo for their duo-prop systems.
Click to expand...

Er, hang on a moment, there's a more important thing at stake here.

Despite your run of various incredibly short lived V8's, you cleared 50 knots, I was never going to do that in a Huntsman, even less so given my change of boat.

So I think its fair to say that in our very fun 10 years or trying to get to Cowes fastest, the Levi hull won, so now, you really don't need to go faster, you need to go...

If that wanky prop was offering a real gain it would be much bigger news, ergo, snake oil.
 
burgundyben said:
Er, hang on a moment, there's a more important thing at stake here.

Despite your run of various incredibly short lived V8's, you cleared 50 knots, I was never going to do that in a Huntsman, even less so given my change of boat.

So I think its fair to say that in our very fun 10 years or trying to get to Cowes fastest, the Levi hull won, so now, you really don't need to go faster, you need to go...

If that wanky prop was offering a real gain it would be much bigger news, ergo, snake oil.
Click to expand...

Agreed, google for Greg sparrow draws a blank, apart from an obituary, maybe appropriate!
 
That was a very impressive video. Personally, I would sacrifice speed and fuel efficiency for slow speed maneuvering (especially on a single engine boat). But to have both is a miracle!
I wouldn’t buy a prop until I found out the cost and availability of the Sharrow.
I would be very interested in how it performs when the boat and prop are heavily fouled. Also, how it performs when it encounters floating ropes, fishing lines, plastic bags etc.
Like anything, testers find perfect conditions for repeatability. But a few seasons of actual ownership and use would be interesting
 
it does look interesting and I really hope it works out but I wouldn't hold my breath, the test data seems off.
They spend too long comparing the performance when the sharrow prop is on the plane and the others aren't and looks to me like they underpropped the boat for the other runs, revs seem high before they get on the plane and all 3 hit the same max revs, which hints to me that they're hitting the limiter or the testers have backed off at those revs. Given the other props are 2 different sizes, one should have over or under revved.
 
peterjaw said:
This video might provide more vivid information.

https://www.youtube.com/watch?v=fO862lWuBdE

It seems that Steve highly recommend the new prop.
Click to expand...

Incredible bias in the reporting. More like a marketing video than a boat test. Very poor.

Highlighting 137% improvement at a specific RPM when one prop was on the plane and one wasn't. Obviously you would run at a few more RPM and get yourself on the plane.

It still seems fairly clear that the new prop provides better fuel consumption. Not 137% but maybe 5-10%. And that is a big deal actually. If that can be replicated on commercial vessels then they have made themselves very wealthy.

But there was nothing about the cost to buy. If I was them that number would be very high indeed for as long as they can get away with it.
And I know how much my props cost to mend when they get dinged........
 
Elessar said:
It still seems fairly clear that the new prop provides better fuel consumption. Not 137% but maybe 5-10%. And that is a big deal actually. If that can be replicated on commercial vessels then they have made themselves very wealthy.

But there was nothing about the cost to buy. If I was them that number would be very high indeed for as long as they can get away with it.
And I know how much my props cost to mend when they get dinged........
Click to expand...

I think if it really did provide 5-10% better fuel consumption they would be targeting the commercial sector first, 5% would be plenty to get them a huge market.
Given they've been testing etc for years, they'd have some tanker showing the real world improvement since switching. There are surely plenty of companies that would take a chance on fitting their vessel with a free prop that promised the chance of saving them millions.
 
I suspect that on a recreational boat there is too much variance to justify fitment. Different loads, throttle settings sea conditions operator discretion and so on. With commercial applications on larger ships conditions are far more controlled and for longer periods of time. You can also make very accurate calculations for speed / time / cost in terms of asset cost, crew, fuel, revenue.

It’s a bit like in a car. If you bring out a device that’s supposed to give 5% fuel Saving I could show you 40% difference through driving technique alone rendering the supposed gains from the Magic device a rounding error in the real world.

Henry
 
I think that you have to give some credibility to Captain Steve. I’ve been following his video and written reviews for years and if he says it’s good then it probably is good. Let’s face it, he is on a lot more boats than we are (and he hasn’t gone all Clarkson, if it’s not a Ferrari then it’s a useless piece of sh1t$)
 
Bouba said:
I think that you have to give some credibility to Captain Steve. I’ve been following his video and written reviews for years and if he says it’s good then it probably is good. Let’s face it, he is on a lot more boats than we are (and he hasn’t gone all Clarkson, if it’s not a Ferrari then it’s a useless piece of sh1t$)
Click to expand...

can't give him any credit for quoting the 137% figure. Nor for not mentioning cost differences.
 
You must log in or register to reply here.

Share this page

Top