Section 1 General

101. Scope

This chapter specifies methods for evaluating the stability and buoyancy of intact (l.e. undamaged) crafts. The flotation characteristics of crafts vulnerable to swamping are also encompassed.

The evaluation of stability and buoyancy properties using this part will enable the craft to be

assigned to a design category (A, B, C or D) appropriate to its design and maximum total load.

102. Definitions

The definitions of terms used in this chapter are as follows.

1. Windage area (AÄÃ )

projected profile area of hull, superstructures, deckhouses and spars above the waterline at the ap- propriate loading condition, the craft being upright (mË )

2. Flotation element

element which provides buoyancy to the craft and thus influences its flotation characteristics

(1) air tank

tank made of hull construction material, integral with hull or deck structure

(2) air container

container made of stiff material, not integral with the hull or deck structure

(3) low density material

material with a specific gravity of less than 1,0 primarily incorporated into the craft to enhance the buoyancy when swamped

(4) rib collar

heavy duty tubular collar fitted around the periphery of the craft and always intended to be in- flated whenever the craft is being used

(5) inflated bag

bag made of flexible material, not integral with hull or deck, accessible for visual inspection and intended always to be inflated when the craft is being used

3. Inclining experiment

method by which the vertical position of the centre of gravity (VCG) of a craft can be determined

4. Loaded waterline

waterline of the craft when upright at loaded displacement mass and design trim

5. Capsize

event when a craft reaches any heel angle from which it is unable to recover the upright without intervention

6. Knockdown

event when a craft reaches a heel angle sufficient to immerse the masthead, mayor may not recover without intervention

7. Inversion

event when a craft becomes upside down

to equilibrium near

and from which it

Ch 5 Stability and buoyancy Ch 5