By Ross Lillistone - Esk, Queensland - Australia

Boomed Vs Boomless
and a few other points about Rigs

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I’ve just read the article, “Traditional Sailing Rigs and Performance” and I applaud Michael Storer for illustrating some excellent points. However there are a number of issues raised in the article about which I would like to make comment.

Boomed Vs Boomless

The most important matter is that of Boomed Vs Boomless. The article states that there are some people around who claim that, “boomless rigs are highly efficient”. Who are these people? What is meant by “efficient”?

Phoenix III leading a Joel White-designed Pooduck Skiff in a race to windward.

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I have not come across anybody who claims that boomless rigs are more efficient than the equivalent boomed rig on all points of sail (assuming that Michael’s definition of efficiency relates to aerodynamic efficiency alone – there are many other ways of defining efficiency).

The use of a boomless rig is dictated by matters other than aerodynamic efficiency, with the most important one being safety when operating in open water. When an un-ballasted boat is over pressed the best course of action is to head up into the wind slightly, and as a last resort, ease the sheets. The problem with a boomed sail is that the aft end of the boom can drag in the water when the boat is heeling excessively, making it impossible for the boom to swing to leeward, and even making it difficult to head up into the wind by use of the rudder. The inevitable result is a capsise. If you are just messing around on an inshore race course that may not be a problem, but for those of us who go out into the big water, it could have very serious consequences.

If you look at working boats which used sail on a daily basis, there are numerous examples of boomless rigs. I don’t want to generalise too much, but a quick glance at the history books will show just how prevalent boomless rigs were when people relied on sail for their living. These people were not fools, and their definition of “efficiency” covered some important territory, including safety and lack of clutter. I do not agree with Michael’s assertion that “boomless sucks” and I think that it is neither prudent, nor polite, of him to say, “Any designer who says that they are "efficient" doesn't have enough sailing experience to make the call or is getting carried away with the promotional spirit of things.”

A few of my friends and I have recently had an excellent opportunity to compare a boomless rig with a boomed rig on my Phoenix III design. Phoenix III is a relatively narrow boat, being 4ft 9in over the gunwales (less to the outside of the planking) on an overall length of 15ft 1-1/2in, so her ability to stay on her feet was something to which I gave a lot of thought. The primary rig was deliberately laid out to allow the mainsail to be set correctly without a boom.

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Head-on without boom – no twist

The term “correctly” refers to when the boat is being sailed hard on the wind. On other points-of-sail the boomless rig does not set in an optimum fashion, but nobody ever has trouble making a boat go when reaching or running – regardless of sail set.

Reefed, lots of twist, but going fast

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In fact, the spritsail as used on Phoenix III is very good in this regard anyway, due to the way the head of the sail is controlled by the sprit.

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Sailing boomless

Sailing same rig with boom attached to mainsail

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What has been discovered about sailing this boat, with and without a boom, is not surprising to any of us: -

  • Without the boom, the mainsail can be eased instantly and safely regardless of the angle of heel;
  • Without the boom there is less clutter in the boat;
  • Without the boom, sheeting tension is high (as is the case with a jib or staysail which is set boomless);
  • Without a boom, the mainsail can be brailed-up, clearing the interior of the boat instantly, and providing a short-term furling arrangement;
  • Without the boom, selection of the geometrically-correct sheeting point is critical and inflexible, but fine control of sail camber on-the-wind is simple and seamless.
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Brailed Up

On the other hand,

  • With the boom, sheeting point is not critical, and sheeting loads are reduced;
  • With the boom, short tacking can take place with the sheet cleated, much reducing workload when short-handed;
  • With the boom it is far easier to maintain sail shape when the sheets are eased – particularly if a boom-vang, wishbone, or sprit-boom is fitted.

Now, having said all that, I have to admit that it is more convenient to use the rig with the boom attached, especially in benign conditions, and I recommend a boom on Phoenix III for general use. But when in the big stuff, the boomless mainsail set-up is safer. It is great to have a rig which can be used with or without a boom, and the change over is almost instant.

Sail Twist

In his article, Michael Storer points out that one of the great advantages of using some sort of vanging device (boom-vang, sprit-boom, balanced lug with downhaul etc) is that it reduces sail twist. This is a very good point, but there are certain conditions under which 20 or 30 degrees of twist in the sail is beneficial to windward performance. This is normally in very light winds, which is also the time when it is most easy to keep things under control without resorting to expensive and highly-stressed rigging components!

Boomless with sheet eased – plenty of twist

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In the case of the spritsail, we have been using a very simple and cheap piece of gear which has allowed us to keep sail twist under good control – even when using the rig in a boomless configuration. The device is a vang leading to the peak of the sprit, and it cost around fifty cents. The sprit vang is not highly loaded, and we made ours from a piece of 3mm (1/8in) Venetian blind cord. Normally we run it through a small fairlead on the rudder head and cleat it in a V-jamber on the tiller. It does not need to be handled from tack to tack.

Congratulations to Michael Storer for bringing up the subject of sensible sailing rigs for the sort of boat which is easy to own and use.

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