Section 5 Hull appendages

5.1.1 The design and scantlings of the skirt are outside the scope of classification; however, the designers are to submit their proposals in respect of the hull attachment detail. The strength of the hull attachment is to be based on the breaking load of the straps, ties, cords or cables to which it is attached.

5.1.2 Where side bodies are fitted, their scantlings will be specially considered. The side bodies are to be designed with respect to the worst possible combinations of loads resulting from cushion pressure, personnel or other concentrated or distributed loads.

5.1.3 Suitable supporting structure is to be provided in way of hull attachments for skirts and side bodies.

5.2.1 The duct is to have adequate stiffness to maintain a clearance between the propeller tips and the inner surface during the most adverse operational conditions. Duct strength, stiffness, hull foundation, and factors of safety will be specially considered based on the operational loads, e.g. thrust and inertia.

5.2.2 The hull supporting structure and attachments of the ducts will also be considered for collision loads.

5.2.3 Air rudder scantlings, hull foundations and factors of safety will be specially considered based on the operational side forces.

5.3.1 Strength of air propeller supports or pylons, hull foundations and factors of safety will be specially considered based on the operational loads, e.g. propeller gyroscopic thrust and inertia.

5.3.2 The hull supporting structure and attachments of the air propeller supports or pylons will also be considered for collision loads.

5.4.1 ACVs are to be fitted with landing pads or skids to facilitate parking. The ACV is to be designed to support the maximum all-up weight on three-quarters of the supports. The landing pads or skids are to be integrated and aligned with the hull supporting structure which is to be additionally stiffened where necessary.