A new and potentially dangerous development in the sport of yachting has recently come to our attention. Originally devised as a design progression from the Thames barge, it should be viewed with extreme caution by any serious mariner.

A number of readers have reported sightings of these experimental craft, noting their cumbersome construction, single hull, lack of lateral stability and extreme slowness. But what concerns us more is the considerable risk to safety posed by these vessels. It is apparent that they can sink with little warning, due to heavier-than-water construction and reliance on tons of ballast. The promoters of such boats are clearly so concerned about the threat to life and limb that they routinely supply underwater umbrellas, automatic bilge pumps, wooden bungs, grab bags and rubber liferafts as standard equipment. Liferafts are semi-submersible shelters that allow the occupants (in extreme discomfort) to reflect on good yacht design while waiting for rescue.

It is of significant concern that these boats travel at dangerously low speeds. Many of them cannot even get across the Channel during daylight! Their consequent lack of manoeuvrability puts them at considerably greater risk when crossing shipping lanes or running to avoid bad weather, irate harbourmasters or getting to the pub after closing time.

These boats have other alarming characteristics. They have a tendency towards uncontrollable rolling in downwind conditions, to the extent that some craft have broken up as a result. This pendulum-swing effect is caused by the underwater ballast and rounded hull shape. Upwind the boats adopt a worrying lean of 30 degrees or more to leeward, making navigation tricky and cooking hazardous. On a recent outing and in spite of ridiculously high fiddles our reporter had to resort to hammer and nails to keep dividers and chart on the nav table, and was forced to wait until motoring in calm waters for his all-day fry-up.

Beaching these impractical craft is fraught with difficulty. Many simply topple over when taking the ground, and can fill with water before coming upright again. Some recent examples have been fitted with detachable keels, which can be swung from side to side before release. This provides sailors with an opportunity to study the factors affecting form stability while sailing (e.g. Mike Golding), or while resting inside (Tony Bullimore).

Most of these boats no longer venture into shallower areas, preferring to remain in deep-water (and deep-pocket) marinas. Sadly for all, they are being actively promoted by the less responsible marina operators who are offering discounts solely on the basis of them taking up less space than proper boats. A beneficial side-effect is that many anchorages, beaches and picturesque drying harbours are uncrowded.

Clearly those who venture to sea in such boats are constantly on the knife-edge of catastrophe, and have to employ extreme vigilance. We urge readers who in a moment of rashness might be tempted aboard them to take great care especially when putting down coffee cups or using the heads.

On no account should multimariners antagonise the poor deluded souls who sail these boats. We should instead treat them with tea, sympathy and if necessary a survival blanket. Offering them a tow by waving a rope’s end will not improve their mood – remember, they are doing their best with what they have and may well be suffering from sea-sickness. Likewise treating them as a roundabout does not foster the camaraderie of the sea. Do not under any circumstances sail past to windward while cooking bacon.