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A vessel engaged in underwater operations (restricted in her ability to manoeuvre, not making way through the water, an obstruction exists on her port side) - lights

  • Description of scenario: Type of vessel: Vessel engaged in underwater operations, when restricted in her ability to manoeuvre, not making way through the water and an obstruction exists on her port side
    Time of the day: From sunset to sunrise and from sunrise to sunset in restricted visibility
  • Rule(s) to be applied: Rule 27 (Vessels not under command or restricted in their ability to manoeuvre)
  • Applying the Rule(s) and comments: In accordance with Rule 27 (d) (Vessels not under command or restricted in their ability to manoeuvre), a vessel engaged in underwater operations, when restricted in her ability to manoeuvre, shall exhibit the lights prescribed in Rule 27 (b)(i) and shall in addition, when an obstruction exists, exhibit:
    (i) two all-round red lights in a vertical line to indicate the side on which the obstruction exists;
    (ii) two all-round green lights in a vertical line to indicate the side on which another vessel may pass.
    In accordance with Rule 27 (b)(i) (Vessels not under command or restricted in their ability to manoeuvre), a vessel restricted in her ability to manoeuvre , except a vessel engaged in mine clearance operations, shall exhibit three all-round lights in a vertical line where they can best be seen. The highest and lowest of these lights shall be red and the middle light shall be white.
  • Lights positions:

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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.