Inflatable Battens

When it comes to headsails, roller furling has been a big hit with voyagers. That’s not always the case, however, when it comes to in-mast mainsail roller furling. While adding to the ease of sail-handling, in-mast main furling has its drawbacks too, mainly the reduction the sail’s roach, which with a standard main is normally supported by plastic or wooden battens. These drawbacks may be a thing of the past however, for users of a new batten-handling system.
AirBattens is a new product that uses compressed air to inflate mainsail battens when an in-mast roller mainsail is unfurled. The batten pockets are pumped full of air, creating the same stiffness in the leech of the sail as a batten. The same 12-volt reversible pump in the cockpit-sited control panel evacuates the battens prior to furling. The unpressurized batten is little more than a slightly thicker section of sailcloth. The system also allows for individual batten control. As the sail is rolled into the mast, one batten at a time can be depressurized, leaving the others still providing stiffening for the sail.
This battening approach allows a mainsail to have a wider, fuller roach, giving the sail added lift when going to weather and added area when going off the wind.
The AirBatten system uses an electrically-powered air pump located in the control panel enclosure on deck. This pump feeds air pressure via flexible tubing to a pressure distribution panel. The panel allows the operator to fill and empty the three or four battens in the sail either as a group or individually. A pressure gauge indicates system pressure. From the control panel, tubing runs under the coach roof and up to the gooseneck end of the boom and then inside of the boom to the midpoint of the spar. A coupling on the outside of the boom transfers the air pressure to spiral flexible tubing, like the spiral wire used to connect a telephone handset to its base. From the boom mid-point the spiral tubing allows extension and retraction of the sail. At the clew of the sail the tubing is incorporated in the hem of the leech and connects to each batten. The sail must be specially made to accommodate the tubing and the inflatable batten pockets.
There are two sailors behind The AirBatten Company, Dr. George Weber and Robert Henderson. Dr. Weber, a vascular surgeon from New Jersey, was sailing his Morgan 45, Morning Light, on the Chesapeake one day when he gazed up at the hollow roach in his mainsail, the shape of the sail necessary for the sail to furl into the mast. He began to think of a way to increase the roach of the sail while still keeping the convenience of in-mast roller furling.
Weber, who laughingly calls himself a “blood vessel plumber,” thought of the technique he had used on patients with heart problems: a thin tube with an inflatable balloon at the end. This same technique used in heart angioplasties might work to address the problem of battens to stiffen the leech of a roller-furling mainsail. Why not use a tube running up the sail to inflate not an angioplasty balloon, but an inflatable batten? Inflatable battens would allow the sail to carry more roach and thus provide more drive. But when deflated, the sail could still be rolled up.
Dr. Weber started a patent search and discovered that a sailor from Port Stanley, Ontario, named Robert Henderson had already filed a patent for just such a system. And, in fact, had built a working system using a fire hose. Henderson had done such a good job, he had won a few races on his 40-foot sloop using his early air batten system. Dr. Weber joined forces with Henderson and the two set about designing the present AirBatten product. They gained the interest of Mark Wood’s UK-Halsey loft in Miami. UK-Halsey Miami has made several AirBatten mainsails. “We’re preserving the convenience of roller furling while restoring the performance of a full roach sail,” Dr. Weber said.
Weber and Henderson will soon introduce a new control panel for AirBattens. Given that sailboat batteries sometimes get flattened, this new panel will have an emergemcy pressure dump valve to allow a user to empty the battens without the need for the electric pump. The new unit will also be equipped with a Schrader valve (the same valve found on bicycle tires) that will allow a boat’s crew to use a manual pump to inflate the battens.

And there are other improvements in store. According to Weber, the company is working on inflatable battens for genoas and for spinnakers. Dr. Weber declined to give a price for an AirBatten system, but suggested that the entire package should cost less than a quality new mainsail. Contact AirBattens at george@airbattens.com. n

By Ocean Navigator