Self Tacking headsail

[jonathansykes]

Herewith a report on this years maiden sail with a new self tacking headsail.

The objective was to have an arrangement that would allow me to sail single handed and tack down a narrow channel without effort, physical exertion, and subsequent large contribution to my Chiropractors pension fund.
To this end it is a huge success.

There is a price to pay but one I consider worthwhile for me. See below.

To compensate for the much reduced sail area down from a genoa I have installed a roller reefing Screacher. Fortunately the previous owner had installed a stainless steel spike on the bow in the shape of a small bowsprit to which I can attache the removable Screacher sail.

To accommodate the self tacker I have removed the forward diamond stay which gave the mast some rigidity and prevented the mast bowing forward. The baby stay has also been removed. The only things preventing the center of the mast bowing forward now are the shrouds. The sail maker did not seem to think that this would be a big problem, and neither do I.

So how does she sail:

Wind 5-10 kts.
Beating to windward in light airs is where there is the highest performance loss due to reduced sail area. This is giving me an apparent wind angle of about 40 degrees. But when the wind comes more aft at 50 to 60 degrees the Screacher can be deployed and can be used all the way round to about 170 degrees off the wind. The Screacher is quite usable on a dead run.
Tacking with the Screacher is easy using the furler to furl in. Tack through the wind, then unfurl again.


Wind 10 - 15 kts.
Now the loss of performance is becoming much much less noticeable and the Screacher is really coming into its own.

Wind 15 - 20 kts.
Beating to windward is now giving an apparent wind angle of 30 to 35 degrees with no significant loss of performance.
Beating up channel is now a one finger exercise with no noticeable weather helm and the rudder is well balanced.
It is now possible to drink tea and tack all at the same time. Just heaven!

The downside:
It is no longer possible to sail using the headsail alone. It just won't go to windward, has no speed, and it will not tack.
Off the wind the sail area is too small unless the apparent wind is 15kts or more. Hench the need for a screacher.

The self tacker cannot be backed (in theory) so a conventional heave-to is not as easy as it was.
For this reason I have attached two control lines that will hold the track car aback. I have yet to test this out in practice.
However because of the poor windward performance under headsail alone I found that with the sheet tight, and the mainsail flying loose and the helm held a-lee Morning Star was quite stable about 60 degrees off wind but making about 2kts forward speed in an apparent wind of 15kts.

I will give a further report at the end of the season as the above was my impression based on just one days sail in calm water.

Any questions feel free to respond.
Hope this season is better than last in the UK.
Cheers folks.

See pictures of the installation at this link:
http://s844.photobucket.com/user/jonath ... ing%20Star