A New Larboard Helm Rule for Power-driven Vessels

Abstract

THE STEERING and sailing rules are changing with the development of available sources of information. This latest development is of special interest, as radar navigation has prompted a return to the principles of the 'Larboard Helm Rule'-if the compass bearing of an approaching vessel does not appreciably change, each of the vessels involved shall alter course so as to place herself to the right of the line of compass bearing to the approaching vessel'.This rule offered simple sailing instructions: each party to an encounter was required to take action. There was no stand-on vessel and no right of way. Our modern steering and sailing rules are based on the right of way of the vessel on the starboard side and this gives rise to difficulties unknown in the days of the larboard helm rule:(i) There are two vessels on collision course, one large and slow-acting, the other small and manoeuvreable; the smaller vessel can easily take avoiding action. As, however, she is approaching from starboard she is the stand-on vessel. The large vessel, though restricted in her ability to manoeuvre is thus obliged to take avoiding action.(ii) The officer on the bridge of the stand-on vessel recognizes risk of collision. The navigator on the bridge of the burdened vessel is distracted from his duty of keeping a proper look-out. Our existing rules require avoiding action on the part of the vessel that has not recognized the risk of collision.The larboard helm rule requires action by both vessels as soon as risk of collision has become imminent. After being in force for 2 3 years it was abolished when in 1863 the leading shipping nation changed its mind and it was decided to replace it by 'right of way'.Before gyro and radar were introduced and before precise course information for the helmsman or automatic pilot was available, the larboard helm rule contained one serious defect. The rule only comes into force when risk of collision has been established and risk of collision could then only be determined to any degree of certainty at very short distance, especially in reduced visibility. The opposition to the larboard helm rule may have been ashore rather than at sea, it must have been a very unpractical instrument for those whose responsibility it was to assess damages and pronounce judgement; no party could then prove the existence of risk of collision but both parties were required to take 403