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Sound signals and supplemental light signals when altering course to starboard

  • Description of scenario: Vessel A: Power-driven vessel underway , when manoeuvring
    Vessels are in sight of one another
  • Rule(s) to be applied: Rule 34 (Manoeuvring and warning signals)
  • Applying the Rule(s) and comments: In accordance with Rule 34 (a) (Manoeuvring and warning signals), a vessel altering its course to starboard (vessel A) shall indicate that manoeuvre by one short blast on her whistle.
    In accordance with Rule 34 (b)(i) (Manoeuvring and warning signals), a vessel altering its course to starboard (vessel A) may supplement the whistle signals prescribed in Rule 34 (a) (Manoeuvring and warning signals) by light signals and indicate that manoeuvre by one flash.
    In accordance with Rule 34 (b)(ii) (Manoeuvring and warning signals), the duration of flash shall be about one second and the interval between successive signals shall be not less that ten seconds.
    In accordance with Rule 34 (b)(iii) (Manoeuvring and warning signals), the light used for this signal shall, if fitted, be an all-round white light, visible at a minimum range of 5 miles, and shall comply with the provisions of Annex I to these Regulations.
    In accordance with Rule 34 (f) (Manoeuvring and warning signals), if whistles are fitted on a vessel at a distance apart of more than 100 m, one whistle only shall be used for giving manoeuvring and warning signals.
  • Signals:

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This project has been funded with support from the European Commission.This publication reflects the views only of the author, and the Commission cannot be held responsible for any use which may be made of the information contained therein.