13.2 Construction
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - International Codes - 1979 MODU Code – Code for the Construction and Equipment of Mobile Offshore Drilling Units – Resolution A.414(XI) - Chapter 13 – Helicopter Facilities - 13.2 Construction

13.2 Construction

  13.2.1 The helicopter deck should be of a design and construction adequate for the intended service to the satisfaction of the Administration.

  13.2.2

  • .1 footnote In general, the helicopter deck should be of sufficient size to contain a circle of a diameter equal to at least the rotor diameter of the largest helicopter intended to use the facility. The helicopter deck should have an approach/departure sector of at least 180° free of obstructions. The base of this sector should be tangent to the periphery of the circle described above as shown in figure 2. Outside the approach/departure sector, obstructions within one third of the rotor diameter from the periphery of the circle described above should not extend above a plane measured vertically from the edge of the deck with a rise equal to half of the horizontal distance from the periphery of the above circle.

  • .2 footnote Where adverse climatic conditions are prevalent, as in the North Sea, a coastal State may, for units operating in its territorial sea or on its continental shelf, specify a helicopter deck of sufficient size to contain a circle of a diameter equal to at least the overall length of the largest helicopter intended to use tile facility. The approach/departure sector should be not less than 210° free of obstruction and should intersect the periphery of the circle described above as shown in figure 2. Outside the approach/departure sector, obstructions within one third of the helicopter overall length from the periphery of the circle described above should not extend more than 1/20 of the helicopter overall length above the level of the helicopter deck. The overall length of a helicopter is the distance from the tip of the main rotor blade to the tip of the tail rotor when the rotor blades are aligned along the longitudinal axis of the helicopter.

  13.2.3 The helicopter deck should have a non-skid surface.

  13.2.4 The helicopter deck should have drainage facilities to prevent the collection of liquids and prevent liquids from spreading to or falling on other parts of the unit having regard to the use of fire-fighting equipment and the possible spillage of fuel.


Copyright 2022 Clasifications Register Group Limited, International Maritime Organization, International Labour Organization or Maritime and Coastguard Agency. All rights reserved. Clasifications Register Group Limited, its affiliates and subsidiaries and their respective officers, employees or agents are, individually and collectively, referred to in this clause as 'Clasifications Register'. Clasifications Register assumes no responsibility and shall not be liable to any person for any loss, damage or expense caused by reliance on the information or advice in this document or howsoever provided, unless that person has signed a contract with the relevant Clasifications Register entity for the provision of this information or advice and in that case any responsibility or liability is exclusively on the terms and conditions set out in that contract.