Colregs Part C - Lights and Shapes (Rule 20 - 31)

Question 1

Rule 20

Answer 1

Application

(a) Rules in this Part shall be complied with in all weathers.
(b) The Rules concerning lights shall be complied with from sunset to sunrise,
and during
such times no other lights shall be exhibited, except such lights as cannot be mistaken for
the lights specified in these Rules or do not impair their visibility or distinctive character or
interfere with the keeping of a proper look-out.
(c) The lights prescribed by these Rules shall, if carried, also be exhibited from sunrise to
sunset in restricted visibility and may be exhibited in all other circumstances when it is
deemed necessary.
(d) The Rules concerning shapes shall be complied with by day.
(e) The lights and shapes specified in these Rules shall comply with the provisions of Annex I
to these Regulations.

Question 2

Rule 22 - Visibility of lights

Answer 2

(a) In vessels of 50 metres or more in length:
– a masthead light, 6 miles;
– a sidelight, 3 miles;
– a sternlight, 3 miles;
– a towing light, 3 miles;
– a white, red, green or yellow all-round light, 3 miles.

(b) In vessels of 12 metres or more in length but less than 50 in length:
– a masthead light, 5 miles; except that where the length of the vessel is less than 20
metres, 3 miles;
– a sidelight, 2 miles;
– a sternlight, 2 miles;
– a towing light, 2 miles;
– a white, red, green or yellow all-round light, 2 miles.

(c) In vessels of **less than 12 ** in length:
– a masthead light, 2 miles;
– a sidelight, 1 mile;
– a sternlight, 2 miles;
– a towing light, 2 miles;
– a white, red, green or yellow all-round light, 2 miles.

(d) In inconspicuous, partly submerged vessels or objects being towed:
- a white all-round light, 3 miles.

Question 3

Rule 23

Answer 3

Power-driven vessels underway
(a) A power-driven vessel underway shall exhibit:
(i) a masthead light forward;
(ii) a second masthead light abaft of and higher than the forward one; except that a
vessel of less than 50 metres in length shall not be obliged to exhibit such light
but may do so;
(iii) sidelights;
(iv) a sternlight.

(b) An air-cushion vessel when operating in the non-displacement mode shall, in addition to
the lights prescribed in paragraph (a) of this Rule, exhibit an all-round flashing yellow light.

(c) A WIG craft only when taking-off, landing and in flight near the surface shall, in addition
to the lights prescribed in paragraph (a) of this Rule, exhibit a high intensity all-round
flashing red light.

(d)(i) A power-driven vessel of less than 12 metres in length may in lieu of the lights
prescribed in paragraph (a) of this Rule exhibit an all-round white light and sidelights;

(ii) a power-driven vessel of less than 7 metres in length whose maximum speed does not
exceed 7 knots may in lieu of the lights prescribed in paragraph (a) of this Rule exhibit an all-
round white light and shall, if practicable, also exhibit sidelights;

(iii) the masthead light or all-round white light on a power-driven vessel of less than 12
metres in length may be displaced from the fore and aft centreline of the vessel if centreline
fitting is not practicable, provided that the sidelights are combined in one lantern which
shall be carried on the fore and aft centreline of the vessel or located as nearly as
practicable in the same fore and aft line as the masthead light or the all-round white light.