1.4 Definitions
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Statutory Documents - IMO Publications and Documents - International Codes - DSC Code - Code of Safety for Dynamically Supported Craft – Resolution A.373(X) - Chapter 1 - General - 1.4 Definitions

1.4 Definitions

 For the purpose of this Code, Unless expressly provided otherwise, the terms used therein have the meanings defined in the following paragraphs. Additional definitions are given in the general parts of the various chapters.

  1.4.1 "Dynamically Supported Craft" is a craft which is operable on or above water and which has characteristics so different from those of conventional displacement ships, to which the existing International Conventions, particularly the Safety and Load Line Conventions, apply, that alternative measures should be used in order to achieve an equivalent level of safety. Within the aforementioned generality, a craft which complies with either of the following characteristics would be considered a dynamically supported craft:

  • (a) the weight, or a significant part thereof, is balanced in one mode of operation by other than hydrostatic forces;

  • (b) the craft is able to operate at speeds such that the function is equal to, or greater than 0.9. Where "v" is maximum speed, "L" is the waterline length and "g" is the acceleration due to gravity, all in consistent units.

  1.4.2 "Air-cushion vehicle" is a craft such that the whole or a significant part of its weight can be supported, whether at rest or in motion, by a continuously generated cushion of air dependent for its effectiveness on the proximity of the surface over which the craft operates.

  1.4.3 "Hydrofoil boat" is a craft which is supported above the water surface in normal operating conditions by hydrodynamic forces generated on foils.

  1.4.4 "Side wall craft" is an air-cushion vehicle whose walls extending along the sides are permanently immersed hard structures.

  1.4.5 "Administration" means the Government of the State whose flag the craft is entitled to fly.

  1.4.6 "Organization" means the Inter-Governmental Maritime Consultative Organization.

  1.4.7 "Safety Convention" is the International Convention for the Safety of Life at Sea, in force.

  1.4.8 "Load Line Convention" is the International Convention on Load Lines, in force.

  1.4.9 "Passenger" is every person other than:

  • (a) the master and members of the crew or other persons employed or engaged in any capacity on board a craft on the business of that craft; and

  • (b) a child under one year of age.

  1.4.10 "Place of refuge" is any naturally or artificially sheltered area which may be used as a shelter by a craft under conditions likely to endanger its safety. Suitable communication and transport facilities should be available.

  1.4.11 "Base port" is a port with:

  • (a) appropriate facilities providing continuous radiocommunication with the craft at all times while in ports and at sea, if required;

  • (b) where Very High Frequency (VHF) is required for the craft:

    • (i) appropriate facilities providing VHF radiocommunication at all times with the craft while in the vicinity of the port; and

    • (ii) access to facilities providing radiocommunication with the craft at all times when operating beyond the range of the VHF facilities provided in subparagraph (i);

  • (c) means for obtaining a reliable weather forecast for the corresponding region and its due transmission to all craft in operation;

  • (d) access to facilities provided with appropriate rescue and survival equipment; and

  • (e) access to craft maintenance services with appropriate equipment.

  1.4.12 "Worst intended conditions" means the specified environmental conditions within which the intentional operation of the craft is provided for in the certification of the craft. This should take into account parameters such as the worst conditions of wind force, allowable wave height (including unfavourable combinations of length and direction of waves), minimum air temperature, visibility and depth of water for safe operation and such other parameters as the Administration may require in considering the type of craft in the area of operation.

  1.4.13 "Critical design conditions" means the limiting specified conditions chosen for design purposes, which should be more severe than the "worst intended conditions" by a suitable margin acceptable to the Administration.

  1.4.14 "Lightweight" is the displacement of the craft without cargo, fuel, lubricating oil, ballast water, fresh water and feedwater in tanks, consumable stores, passengers and crew and their effects.

  1.4.15 "Maximum operational weight" means the overall weight up to which operation in the intended mode is permitted by the Administration.


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