Backstay sail

[oldbilbo]

I've found one of these. In fact, it's the first I've encountered in several decades.

I can figure out where it is intended to fit. Does anyone have any experience to share re how useless/ful it may be?

 

[nauticalnomad]

I've found one of these. In fact, it's the first I've encountered in several decades.

I can figure out where it is intended to fit. Does anyone have any experience to share re how useless/ful it may be?

This guy sails with one on his charter boat

http://www.goodfortunesails.com/

 

[Twister_Ken]

I've found one of these. In fact, it's the first I've encountered in several decades.

I can figure out where it is intended to fit. Does anyone have any experience to share re how useless/ful it may be?

Seem to recall there was one of us (a jock?) who reckoned it did the business when anchored, to stop the boat sailing around the chain.

 

[KellysEye]

I assume you mean a riding sail which is a triangular shape. Our is hanked to the mizzen topping lift and tied to the mizzen mast. On a sloop after hanking it to the back stay it might be better to tie a line each side to the the guard wires, in front of a stanchion. They signicantly cut down the snatch load on the anchor and we use ours every time we anchor.

 

[Poignard]

This?

http://www.rocna.com/kb/Riding_sails

Or this?

http://www.bannerbaymarine.com/

 

[prv]

As hinted at by previous posts, it's not clear whether you mean a "mule", set aft of the main backstay of a ketch and sheeted to the mizzen masthead to provide extra drive while sailing, or a riding sail, set forward of the backstay of a sloop or cutter to provide stability while anchored.

Pete

 

[Juggler7823]

Here's a picture of a riding sail in use. It can't be seen easily in the photo but the sail has 2 pieces held open by his boathook.

 

[Twister_Ken]

Here's a picture of a riding sail in use.

That's the fellow I was thinking of.

 

[oldbilbo]

Hmm. Interesting shapes. But not quite what I have here, I'm afraid.

This sail, made by Westaways on whom I shall shortly call, is single-ply - not V'd like Piota's or as in Parsifal's links.

The short side has 3 piston hanks and reinforced with what otherwise might be described as a luffrope. I shall call this side the 'luff'. It's dimensions are 77".

The other two sides are 108" - I shall call this the 'leech' - and 101", which I'll call the foot, mainly because of the orientation of the sailmakers' logo.

The BMU-rigged boat has a cutaway forefoot and a long keel, like a Contessa 26/Folkboat, and I understand the sail was intended/set as a form of riding sail, to keep the bows up somewhat in heavy weather and lying-to.

There's probably a better way....

 

[snowleopard]

url]http://www.rocna.com/kb/Riding_sails[/url]

I wonder where it's made and what spec the material is

The concept looks like a possible solution to the extreme hunting I get with my wing mast as discussed a few months back. I guess it's worth lashing something together to see if it works before getting one made up to suit my strange rig. Now how do I sneak a couple of sheets out of the airing cupboard without SWMBO noticing?

Anyone have experience of whether the splayed shape is more effective than the traditional single-thickness sail described by the OP?

 

[prv]

From the description, I wonder if it's a trysail designed to hank onto a wire running up next to the mast? I've certainly seen pictures of trysails on gaff-rigged boats that were wider than they were tall. That would fit with the description of lying-to in heavy weather.

Pete

 

[Deleted member 36384]

... Anyone have experience of whether the splayed shape is more effective than the traditional single-thickness sail described by the OP?

No direct experience. However, from Piota's web site/ Blog and posts on here he had tried out various styles and found his shape to be the most effective by far. I took interest and read up on it because my high bows blow about a lot.

 

[Poignard]

Anyone have experience of whether the splayed shape is more effective than the traditional single-thickness sail described by the OP?

I don't but - the 'splayed shape' must come into effect at a lesser angle of yaw than a one-piece riding sail would, ie there would be a quicker reaction.

 

[BrianReynolds]

Hi
We have had a riding sail made for us, along the lines you describe ie single ply, piston hanks etc. we have used it when at anchor, when windy and on a long anchor chain. Our long keeled boat "sails" either to the side of the anchor in a strong wind, then drops back and repeats the process.
When hoisted the sail greatly reduces the movement and ultimately the strain on the anchor - as soon as the stern is out of alignment with the wind the riding sail pushes the stern back so the boat is head to wind again -so there is some moving around. Some ketches leave the mizzen sail up to achieve the same effect.
We have found that it is quite hard to physically set the riding sail (especially when it is windy, and the foreward edge needs to be as tight as possible, using the aft end of the boom and the sheet winches.

Brian

 

[machurley22]

Here's a close-up of Piota's riding sail.

 

[Poignard]

It might also help to counteract bow windage when reversing out of a marina berth with a cross wind blowing towards the dead-end.

 

[Babylon]

Here's a close-up of Piota's riding sail.

Crikey! That looks like a VTOL hang-glider!

 

[Vegable]

Piotta was owned by Keith Stanley who ran a Sailing School - North Scotland Sail I think and used to sail around 5,000 miles a year out of Arisaig. I learnt my keelboat sailing with Keith and he didn't give out certificates lightly. He used to say "If I don't test you, the sea will." and he did test you. I've been with him a few times when he refused to issue RYA certificates.

Below is from Keith to me when I asked him about it. I have a ketch and was thinking about copying it but in the end I didn't do it as there didn't seem to be enough room aft of the mizzen mast to lash the sheets to a deck fitting i.e. I ran out of deck. It's the story of how it came about and how Keith made up the sail to suit Piotta.
The photo's shown in previous posts illustrate it well and I don't have any other pictures myself although I have seen a u-tube clip of it in action somewhere.
Mike


Riding Sails

What's wrong with a storm jib or staysail hanked on the backstay and sheeted forward, hard?
Not much, in an ordinary gale. I used one that way on a few occasions: it did not prevent the boat ranging about in gusts, but it limited each sheer quite effectively. It seemed to be a useful and "proven" practice. Until 13th June 2000.
The wind had increased steadily through the previous day as we awaited the long-forecast arrival of a deep depression, born as a Caribbean hurricane. We had been on passage from Cromarty Firth to Shetland and, with no need to take a pasting, we had diverted to take shelter in East Weddel Sound, Orkney. When the evening forecast predicted Force 10, we thought it prudent to
move close in the lee of the old blockship behind to the Churchill Barrier. We laid twin COR anchors about 30 degrees apart on maximum scope and stripped the deck forward of the cockpit of all removable windage.
By late morning of the 13th we had 50 knots across the deck, steadily increasing. The boat began to sheer about in the gusts. Orkney Harbour radio now forecast the peak to come in the afternoon, with gusts of 70-80 knots. It was time for a riding sail, our 10oz. triple-stitched "bullet- proof' storm staysail, hanked to the backstay, twin-sheeted forward and winched flat. As expected, sheering was reduced. But the wind rose further still, and every time the boat tacked the sail was furiously thrashed, visibly whipping the mast. The whole boat was shuddering, heeling and straining her cables before the riding sail could correct. In less than half an hour the violent attrition was disintegrating the cloth at the hank eyelets. The sail had to come down.
The following hours were tense. I tried using engine power hold her head to wind and ease the load on the cables but it only increased the sheering. I calculated windage loads and became concerned about cable shackles. Our last resort would be to run to the open sea if they failed. We dropped the boom to the deck and lashed it; fed the trysail into the track, lashed in down and hanked on the storm jib with sheets attached, still in its bag. The wind was shrieking: it threw sheets of water at us over the Barrier, stinging, blinding. The very idea of any control under power was preposterous. The prospects under sail were not a lot better: we were listening to the VHF traffic between Shetland Coastguard and the rescue helicopter busy recovering a single- hander from his capsized catamaran 70 miles off Shetland.
By evening the wind was down to 40-50 knots (Force 9). Orkney radio reported that during the afternoon the windspeed had not fallen below 64 knots (i. e. not below hurricane force) for five hours.
A month later, anchored in Balta sound, we watched an American single-hander arrive and
anchor close by. We met John Armitage and exchanged recent experience, including the big blow. He had been in Norway, happily using a home-made riding sail, thoroughly tested in ten years cruising in his 34-ft live-aboard sloop. He kindly demonstrated it on Piota and gave me a sketch of the design. It is ideal for a high-aspect-ratio sloop or cutter where it can be set in the space between the boom end and self-steering gear, but I think the principle could be applied to most ketches. John told me he had not tried to patent it because he had seen an article in an American magazine describing a similar idea.
The 'V- Twin' concept: Consider twin riding sails joined at the luffs, clews held apart by a short
spar and sheets to the stern-rail. When precisely head-to wind both sails are under pressure, generating equal and opposite forces: but the slightest sheer instantly unbalances the equation, producing a correcting force. Each sail blankets the other's lee side: there can be no flogging , no attrition, no shuddering. Consequently, the canvas can be much lighter than a flat sail (John made his from odd scraps of spinnaker cloth on board) and because it is more efficient it can be smaller

The sail works!
I adapted John's design and its gear for easier handling on Piota and had Owen Sails make it. Taking five minutes to set up, less to stow, it well used. It is so effective in keeping the boat steady that when down below at anchor in moderate winds we could believe we were in a flat calm. The steady load on the anchors is increased, but the peak loads caused by sheering are markedly reduced and there is no snatching. In a blow, with waves in the anchorage, there is only slight pitching; no sheering. At times we have gone up to the cockpit believing the wind had died down only to find it still blowing hard. A widely experienced skipper who cruised Faeroe with us reckons that one of these should be standard equipment on every cruising yacht!

We once left Piota on a mooring with riding sail set, and she sat there happily through a storm that caused other yachts to break free. For some reason I had not set it at Arisaig in August 2001 when a severe gale broke a shackle (new!) and Piota was driven ashore. The sail might well have prevented the incident.


SETTING :
The following sequence presets it before hoisting. (the main halyard is used to support the boom to release the topping lift for the riding sail)
1 The tack has a D-ring for a strop to the mainsheet track, or two spliced lines, pre-set to length, angled forward and outboard to strongpoints (in Piota's case, cleats on the coamings).
2 The clews are spread apart by a light spar poked into the cringles (or D-rings): permanently spliced sheets are doubled under the sternrail inboard of its stanchions, and back to the
clews; secured by eye-splices over the spar or clips to the D-rings.
3 The topping-lift is clipped to the head: a rapid hoist & tension on a winch: sail set!
The trick, at the design stage is to make a mock-up of the sail edges in 'string' and adjust dimensions (sail and spar) so that when fully hoisted and tensioned the luff is clear of the boom,
the sheets bisect the clew angles (with the spar in place), and the spar is clear of the backstay, (either ahead or abaft). Contrary to what might be expected, it is neither necessary nor desirable to attach anything to the backstay. When the dimensions are all compatible and the sail is set flying it is stable; and silent!

Specification of the sail for Piota:
Dimensions: (Hollows in brackets): Luff, 8ft (1.5in.) : Leech, 9ft.8in (1. 75in) : Foot, 5ft.6in (1.0in) Cloth: a light polyester (dinghy) sailcloth. (Preferred to spinnaker nylon, which distorts too much underload)
To join the twins: lay one on top of the other, corners corresponding, then turn the top one over like a page of a book to leave the luffs edge-to-edge: Join with 2" flat webbing: (it stiffens and rounds the luff: no eddies, no turbulence!)
Tabling: I had lee-lines and foot-lines put in to deal with any flutter, but there is none. Fittings: D-rings (or cringles large enough to accept a spliced sheet and tapered end of the spar) .§QM : I use a boathook with a plastic fitting at both ends (to avoid having to stow an extra spar).

 

[Sandles]

Very interesting. I assume that Piota is a monohull ? What is her length ? (So that I know whether to resize the sail for my 29' yacht.) Also I am not sure what you mean by "Hollows in brackets." Thanks. (I seem to be about 9 years behind !)

 

[Fascadale]

Great to reread Keith Stanley’s description of “Piota’s” riding sail

“Piota” is a Van der Stadt designed Pioneer 10, a 32 ft monohulled sloop. Keith very sadly had to part with “Piota” as his health deteriorated. She was an immaculately equipped and maintained vessel

Keith was a somewhat legendary sailor and instructor who lived near Inverness. A mainstay of his sailing school were ten day voyages to from Inverness to Arisaig, with a change of clients there then ten days back to Inverness. He was also a very frequent visitor to St Kilda. A great sailor, and very happy to share his knowledge and experience. I still use his notes for crossing the Pentland Firth

For many years Keith posted here first as “Piota” then as “Piotaskipper” He had a final user name (that I have forgotten) that he used after selling the boat.

I last heard of “Piota”about three years ago. She was for sale ashore in Kintyre

Now that I see his sizes and instructions for the riding sail I may try to make one myself.