What's a Swing Rig?

Photo at left shows a Marblehead with a swing rig, mainsail swung to right, jib to left, click on image to see larger photo, note the jib club swivel attached to the forward boom extension

Ed note: Nick is the Chairman of the Racing Rules Committee
ISAF RSD Chairman of the Appeals Committee MYA
National Judge RYA One time Radio Marblehead racer - National and International

Re: Swing Rig

From: Nick D Weall, email ndweall/#/cotops.ltd.uk
Date: 5/26/99
Time: 1:58:26 AM

The jib boom is connected to the main boom by means of the forward extension of the main boom, the jib boom is attached to this extension by means of a simple swivel line. The rear of the jib boom is then tethered with an adjustable length of line that simple allows you to set the desired slot by hand. You cannot adjust it by radio control. The main boom including the extension is either fixed to the mast section and thus the mast has to rotate in its housing (Usually an aluminum tube with the mast having a couple of PTFE bearing rings one on its foot and one where it is near the top of the tube., the alternative is that the main boom and extension is made with a circular hole for the mast to go through thus the main boom/extension rotates around the mast. The main boom has a line attached as usual leading to the winch.

Swing rigs permit easy off wind performance, the can lose a degree or two of windward performance and on a dead run can be slightly inferior to a conventional rig. In the UK it is quite usual to use swing rigs for the high aspect rigs and conventional for the lower area rigs used when the wind gets up over force four.

Re: Swing Rig

From: Lester Gilbert (UK) email l.gilbert/#/cant.ac.uk
Website at http://ourworld.compuserve.com/homepages/lestergilbert
Date: 5/28/99
Time: 5:09:18 PM

Comments

Derek Harvey tells us ("Sails", Adlard Coles, 1997, p94) that Roger Stollery devised the "swing rig". It was mounted on a Bembridge Redwing that won so many races it was banned. Both Roger and his son Peter rank high on the UK M and IOM ranking lists.

Tony Marchaj tells us ("Sail Performance", Adlard Coles, 1996, p213) that the swing rig was invented by Carl Boss in 1974. He provides a 1984 picture of the rig on "Elf Aquitaine", a record-breaking cat.