Fishing Vessel Safety Regulations

17 On a fishing vessel, the diameter of rudder stocks for rudders fitted with bottom pintles shall not be less than

• (a) as shown in the following table:

  Length of ship in metres	Diameter of rudder stock in millimetres
  12	50
  15	56
  18	62
  21	72
  24	82; or

• (b) that calculated by the following formula:

  D = 16.67 cubic root (A x R x V²)

  where

  D =

  diameter of rudder stock in millimetres,

  A =

  total area of one face of rudder in square metres,

  R =

  average horizontal distance in metres between the trailing edge of rudder and the centre line of stock, and

  V =

  maximum speed of vessel in knots, or eight knots, whichever is the greater.