Yellowfin Vairable Pitch Surface Drive

An 18-tonner with Bravos is being used as a point of comparison against twin 700hp surface drives? That's a lot of power to put through a Bravo, especially on a boat that heavy- they're generally meant for smaller craft and would certainly be sluggish and inefficient on something that heavy. Comparison with shaft drives is a good starting point though, since that setup is common on boats like that. How does it stack up against an Arneson?
No doubt that it's a cool idea. But as has been said by many, naive marketing hype is meaningless. Volvo IPS was hardly a new idea; it's simply a small-craft version of the drivetrain our local car ferry's been using since the '70s. The Yellowfin drive is a radical departure from anything that came before and so there is an expectation that solid engineering data- or at least a decent photo of the thing- will be published.
Petter- It sounds like you might be affiliated with the company somehow? Perhaps you could pass on our accumulated advice to the marketing team. I'd like to see this thing succeed, and preferably on engineering merit. I don't want to see a neat idea killed by lousy and ill-informed marketing.

 

There are videos on the company website.

http://www.yellowfin.com/VSDTechnology.asp


Pericles

 

Yellowfin News

This British company is offering a complete engine & propulsion package for new build boats that does away with the need for rudders and bow thrusters. The site has videos and reprints of recent articles in the boating press. http://www.yellowfin.com/VSDTechnology.asp

Six units will handle power from 60 hp up to 2000 hp and it is claimed that they could replace twin 875 hp diesels with 510 hp diesels in a Sealine T60 and go 5 mph faster. MBY November 2006.

The Shipnboard article has a good illustration.
http://www.yellowfin.com/pr_shipnboat.pdf

The blades even fold like petals on a flower to allow the boat to take the ground without damage. One engine, two drives!! Roll on May 2007.

Pericles

 

It's like watching videos of UFO's, what's the deal with the lack of pictures, besides the demo model. If it's for corporate secrecy just say so. The videos could be of anything for all we know.

 

I asked Yellowfin for more info and this is all I got:

"Dear Guillermo
Thank you for your interest in VSD.
We are currently working towards the production launch of VSD and aim to have product in the market in time for next season. Ultimately there will be a range of drives catering for single, twin and multi-engined configurations from 60hp - 2000hp.
We have been working with certain engine manufacturers for some time now and VSD will be available as a total propulsion package (engine and drive system) only. World-wide distribution will be via these engine manufacturers dealers / representatives.
We are concentrating on the new-build market initially, but hope to offer a re-power / retrofit service for existing craft once the new-build market is up and running.
Further technical documentation, photographs and distribution details will be posted on the website as we get nearer to launch....." :?:

 

Has there been any new information released about these drives? or anything relating to their single inout dual output design?

Time

 

http://www.yellowfin.com/Financial_times.pdf

http://www.yellowfin.com/Finalcial_Mail.pdf

Getting closer.

Pericles

 

I just found this, whilst backgrounding and trawling for more info, and find it an intriguing and interesting concept that may be of relevance to me, so I emailed for more info today.

We will see what we will see.

 

It has been interesting reading the comments regarding Yellowfin VSD propulsion. First off, I am not a principal or employee of Yellowfin but do have extensive independent knowledge of the project and submit both the pro's and con's of the Yellowfin VSD from my point of view.

The Yellowfin system does work, I have extensively tested and sea trialed it and it has the speed and maneuvering performance claimed. The yet untried concepts of inertial navigation combined with ride control would make this one of the most innovative products to hit the market in years.

However the company has been unable to prove their fuel savings, efficiency and environmental claims even to their contracted customers. The marketing hype, with unsubstantiated figures, has been used over the past four years to extract further investment funds from innocent investors, then an aborted public offering and now, currently towards British taxpayer sources as a last ditch bail out effort. According to one of their Directors, they need 12 million pounds to go to production. Over the past three years they have been unable to even find an engine manufacturer to partner with them. Do the MTU's, Volvo's, Cummins of this world know something we don't?

The current planned selling price of a 500 hp VSD system ( 2 units ) is 74,000 pounds excluding the two engines needed to drive the units and until Yellowfin can raise the capital they are unable to produce. It would take a considerable
fuel savings to justify such a capital expense yet Yellowfin believe their market lies in recreational boating.

Their failure to deliver contacted units has caused one customer to file a claim for damages in excess of one and a half million pounds against them. This factor, together with the lack of support from the marine propulsion industry and the current world economic situation does not bode well for Yellowfin's long term future. It is a pity, as in my opinion, the system, properly developed would be a vast improvement on existing technology.

The problem stems not from brilliant engineering of the designer but from greed, arrogance and egos within the self anointed entrepreneurial division.

 

SeaHunter - Strong words. You are quite a distance from the UK, or are you on your travells?

PGNB

 

anyone got more info?

I see beserk designs has a few boats with it in it?

 

As predicted, they have failed miserably. See article in April 2009 edition of Motor Boats Monthly. Page 29

 

don't have access the that article. Care to share what has transpired?

 

Copy of article in jpeg format. Hope it is readable.

 

OK...so i guess it was a flop...good idea poor execution then.
Back to standard surface drives and legs for awhile then.