There is always a risk of capsize on small open sailboats. Modern dinghies are designed to be easily recovered and able to resume sailing. But on traditional open boats and "sail and oar" boats, recovery may be difficult and to bail out at sea almost impossible. This is a major safety issue.
|Recovery test of the new Ilur 2011 by Icarai boatbuilder|
|It is not easy for a single crew to capsize the boat!|
In Europe, the RCD (Recreational craft directive) has set up a standard to comply with: “small craft stability and buoyancy assessment and categorisation”, ISO 12217. These rules are compulsory for all boats marketed in the European Union, with some exclusion as historical boats and amateur boats “built for own use, provided that they are not subsequently placed on the EC market during a period of five years”. However, some countries, France for instance, ask home built boats to comply with.
ISO 12217 has been written by a group of expert, including US coast guards representatives, and, despite many critics (the RCD penalize small traditional boat-builders), is a good reference to ascertain a satisfactory safety level. This document is very huge and I will only give hereunder a practical way to implement it in the only case of small open sailboats under 6 metres for design category C or D
. Note that ISO standards are not free and are expensive. The following lines are not a copy of the official document, but only a simplified and practical description. Two tests are to be performed, a “capsize-recovery test” and a “flotation test”.
|The crew "walk" on the mast to be sure the boat is not able to make a 180° capsize|
Preparation: fore-and-aft sails hoisted, centreboard down.
Condition of test: calm conditions, with the boat in normal sailing conditions (the motor, if any, may be replaced by an equivalent weight and buoyancy at the same location).
Crew: the minimum crew, so in general one person only (75 kg, as far as practicable!). If recovery is not possible with one person, then the minimum crew is to be increased.
The boat is capsized at approximately 180° or the maximum practicably attainable equilibrium heel angle, with the crew in the water alongside. Of course sufficient depth of water shall be available.
Wait 5 minutes. The boat shall not sink!
Right the boat by the crew without any aid. No more than three attempts are permissible, each of which shall be limited to 5 minutes duration.
|With side buoyancy compartments, it may be impossible to start recovery|
After the boat has been righted and one person with a mass of not less than 75 kg has reboarded, the boat shall float such that the residual freeboard would enable the boat to be pumped or bailed out. The longitudinal position of that person may be optimized to ensure sufficient residual freeboard for pumping or bailing.
|During this test, the sail was missing|
Without bailing the boat at all, after the remainder of the crew up to the crew limit have re-boarded, the boat shall float approximately level with not more than one-third of the deck or gunwale submerged, for not less than 5 minutes. Check that the level of water inside is the same as outside. For that purpose, heel the boat in order to submerge the sheer.
I recommend to take pictures of the test and to make a detailed written report. It may be useful, in particular if the boat is later involved in an accident.
This test is a good way to be prepared in case of a capsize which always happens unexpectedly. In many cases, it allows to detects some problems: the helm is lost, the centreboard has rotate inside the case, the mast escapes from step, the bailer is too small (a foldable bucket may be better), etc... You may modify your boat accordingly: handles on the hull, for example a bilge keel of appropriate shape, eyebolts into keel to attach a rope, buoyancy addition...Therefore, it is always advisable to do the test, even if you have bought a mass produced boat.
All my boats are designed to comply with the standard. However, due to varying construction methods, wood density, rig options, there is always some uncertainties. I thank those who will pass on their feed-back.