Tandem Keels

[davidtargett]

I am buying a new Bavaria 37 which is offered with two keel options. One is a conventional 1.95m fin and the other a 1.6m shoal draught tandem fin. Has anyone any experience of these "tandem fin keels" particularly on a Bavaria?
Thanks, Dave T

 

[jamesjermain]

No experience of a tendem on a Bavaria but in general it provides very good windward performance for comparatively little draught because the interaction between the two elements which generates lift to compensate for the lack of depth. It tend to make a boat feel bigger than it is by damping down pitching and improves directional stability by virtue of its length.

It suffers from the usual problems of shallow draught in that it loses grip when the boat heels to more than, say, 15 degrees.

Down wind there is not much difference in performance between the tandem and a fin although the tandem will be straighter running

 

[Peppermint]

Re: Warwick Collins

Developed "Flying Boat" to show how tandem keels could be successful up wind. A search might through up some details. I think Sadler and Seawolf tried them. One of the yacht mags did a comparison test as I remember.

Good Idea on a Bav. Two keels that is. Might be handy having a spare.

 

[Peppermint]

Re: Have a look here

http://www.westboundadventures.co.uk/gallery/yacht

 

[Kilter]

Re: Warwick Collins

[ QUOTE ]
Good Idea on a Bav. Two keels that is. Might be handy having a spare.

[/ QUOTE ]

Like it! /forums/images/graemlins/smile.gif

 

[davidtargett]

Thanks for the advice James. You have confirmed what I had been led to believe re their windward ability. I am trying to get to see the stability curves for comparison and if they look similar then I will probably go for the tandem keel.... could be a possible review subject for the magazine? Wasn't there a series of articles on keel design a couple of years ago?

Still keen to hear from anyone that actually has one.....

Thanks for the "Flying Boat" info, I'll do a search...

Thanks everyone,
Dave

 

[jamesjermain]

It's interesting the tandem keel is making a return after so many years. Etap is also offering it as an option. First time round it hardly made a ripple. I wonder how it will be received this time?

 

[Sans Bateau]

Several models in the ETAP range have offered tandem keels for some years now, about 10 years at a guess. There is a new ETAP 28S being launched on the market next spring, that will have the option of a tandem keel.

 

[Twister_Ken]

If you're looking into Tandem Keels then I think the designer Warwick Collins was behind the revival of the concept.

For interest, look also at the forward keel concept often seen on envelope-pushing 6 meters.

 

[Sans Bateau]

Ken

I'm not particularly a student of the tandem keel, I have only mentioned it because its not that new to Etap. Just had a look at their web site and all the Etaps are available with tandem keel, yes even the new 46DS!

I can't say I would rush to spec a tandem keel if I where to be buy new though. Although there is probably nothing wrong with them.