11.1.1 General
Clasification Society 2024 - Version 9.40
Statutory Documents - MCA Publications - MGN 280 - Small Vessels in Commercial Use for Sport or Pleasure, Workboats and Pilot Boats - Alternative Construction Standards - 11 Intact Stability - 11.1 All Vessels - 11.1.1 General

11.1.1 General

  11.1.1.1 The standard of stability to be achieved by a new vessel should be dependent on the maximum number of persons permitted to be carried and the intended area of operation.

  11.1.1.2 The following vessels are required to be provided with a stability information booklet which is approved by the Certifying Authority:-

  • .1 vessels operating in Category 0 or 1; or

  • .2 vessels carrying 16 or more persons; or

  • .3 vessels carrying cargo greater than 1000kg; or

  • .4 vessels fitted with a lifting device as defined in 11.6; or

  • .5 vessels towing where the towed object's displacement is greater than twice the displacement of the towing vessel. See Section 11.7; or

  • .6 seagoing pilot boats.

Note Motor vessels covered by .1 or .2 are not required to carry stability information booklets if the stability is assessed under section 11.3.8 using ISO 12217 Part 1 'Small craft - Stability and buoyancy assessment and categorisation - Non-sailing boats of hull length greater than or equal to 6 metres'.

  11.1.1.3 A vessel carrying 15 or less persons, carrying 1000kg or less of cargo, and operating in Area Categories other than 0 or 1 shall either comply with Section 11.1.1.2 or be subject to a simplified assessment of stability, and is not required to be provided with approved stability information.

  11.1.1.4 If a vessel cannot meet the stability criteria given within Section 11, it should be specially considered by the Certifying Authority, and such cases should be reported to the Administration.

  11.1.1.5 The stability of sailing vessels fitted with non-fore and aft rigs, or moveable/variable ballast is to be specifically considered on application to the Administration.

  11.1.1.6 Stability of a vessel which will operate in sea areas where ice accretion can occur should be specially considered by the Administration with regard to icing allowance and stability standard. (See also Section 6.10)

  11.1.1.7 For stability requirements for an inflatable vessel or a vessel fitted with a buoyant collar, see Section 11.5. For stability requirements for a decked vessel fitted with a lifting device, see Section 11.6 and for a decked vessel engaged in towing, see Section 11.7.

  11.1.1.8 A sailing multihull over 6m in length should be provided with a Stability Information Booklet approved by the Certifying Authority.

  11.1.1.9 Where a monohull vessel cannot comply with the specified criteria, due to its hullform displaying stability characteristics similar to that of a multihull vessel, the stability criteria for a multihull vessel may be applied, as appropriate for sailing or motor vessels.

  11.1.1.10 A motor multihull type vessel failing to comply with the criteria of either Section 11.3.6 or 11.3.7 may be given special consideration. In such a case, calculations should be submitted to the Administration for assessment.

  11.1.1.11 All vessels, other than those vessels deemed unsuitable for carriage of the booklet by the Certifying Authority (i.e. vessels with no cabin or shelter), are required to carry the relevant copy of the MCA Stability Guidance Booklet (Motor or Sail). Where a booklet is not carried on board a copy is to be made available to crew ashore. These booklets are available free of charge from the MCA or Certifying Authority. Although they contain generic safety advice, the stability and freeboard data already generated during the survey process should be appended to the booklet in the relevant section. It is the responsibility of the Certifying Authority to supply this information, and the owner/managing agent is to ensure this data is included.

Parent topic: 11.1 All Vessels
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