Master’s blog. COLREGS72, Rule 17. Action by Stand-on Vessel

Despite all the impressive electronic assistance designed to enable deck officers to avoid collisions, collisions still occur. The answer is, and always has been since radar was first introduced, that the rules of navigation set out in the COLREGS must still be applied by deck officers.
Foreword to ‘Collisions: How to Avoid Them’ , the Hon Mr Justice Nigel Teare, Admiralty Judge at the Royal Courts of Justice in London.


From practical viewpoint application of Rule 17 should seemingly provide no difficulties. Stand-on vessel’s first duty is to keep her course and speed until the moment when it becomes evident that give-way vessel is not taking appropriate action; it is when she may take action to avoid collision. After that, if situation develops so that collision cannot be avoided by the action of the give-way vessel alone, stand-on vessel becomes obliged to take such action as will best aid to avoid collision.

However, as far as my personal experience goes, deck officers usually ignorant about distinction between sections (a)(ii) and (b), i.e. instances when stand-on vessel first ‘may’ and later ‘shall’ take avoidance action, and have little idea about objective assessment of distances between vessels at both stages. Distinction is important because it imposes different degree of duty on stand-on vessel and accordingly the law treats differently violation of ‘may’ and ‘shall’ obligations which is finally reflected in apportionment of collision claims.

While one may be sceptical about post factum assessment, decision of the court is crucial for both parties because it objectively estimates degree of fault of both vessels in carrying out their navigational duties and draws the borders of parties’ collision liabilities. For seagoing personnel it is important to apprehend, from case reports cited below, an objective test estimating degree of blame for each side, as it applied by the court from case to case.

Avoidance actions as provided in sections (a)(ii), (b) and (c) assumed to take place on distances between vessels less than 4 miles (see Owners of The Ship "Topaz" v Owners of The Ship "Irapua" [2003] EWHC 320 (Admlty)).

Tolerance of stand-on vessel’s actions

The court, usually advised by the marine experts, appreciates that manoeuvring of vessels speedily approaching each other on close ranges is actually an emergency action sometimes carrying out in the agony of the moment. The law says that conduct of a prudent seaman in such circumstances shall not to be tried by mathematical calculations subsequently made. An illustration to these words one can find in the Court of Appeal decision in The Selat Arjuna and Contship Success [2000] 1 Lloyd’s Rep 627, which concerned to collision between small coaster Selat Arjuna (stand-on vessel) and a container vessel Contship Success which suddenly altered her course to starboard and collided with the coaster. Clarke LJ analysing actions of stand-on coaster held that:

The master of Selat Arjuna was on any view put in a very difficult position by the navigation of Contship Success. He could not have known what Contship Success would or might do. Hard to port is rarely the appropriate action. He could not have supposed that Contship Success might go hard to starboard. In all these circumstances, while he might have gone hard to port, I would not characterize his failure to do so as negligent or in breach of duty. It follows that, while I would hold that he should have appreciated that Contship Success was altering to starboard earlier than he did, even if he had, I would not blame him for standing on.

Now coming back to the Rule 17, it is naturally to suggest that law assumes certain tolerance necessarily to be given to the actions of a stand-on vessel, as to the vessel usually acting under the pressure of the moment.Such tolerance has uncertain borders but generally understood as applied to legally valid actions which were not completely correctly performed, for example when collision avoidance action of stand-on vessel was correct but not effective enough to avoid collision.

If in that moment of extreme peril and difficulty such other ship happens to do something wrong so as to be a contributory to the mischief, that would not render her liable for the damage, inasmuch as perfect presence of mind, accurate judgment, and promptitude under all circumstances are not to be expected.
The Bywell Castle (1879) 4 PD 219

The court will carefully consider the factual background and especially witnesses’ statements to determine whether or not the officer of the watch acted under any stress or sense of imminent danger. For example in one case the master had two and a half minutes to undertake collision avoidance action, during which time he first set helm hard to starboard and then changed his mind and set it hard to port. It was held that such actions cannot be properly categorised as an agony of the moment case.

Rule 17(a)(i)

Another very important point is to grasp that in instances to which Rule 17 applies, the law generally considers it as justifiable that stand-on vessel keeps her course and speed as long as it possible to do so without immediate and manifest danger. Therefore so far as a stand-on vessel must keep her course and speed, she is not at fault if by her earlier manoeuvre collision could be avoided, when same collision could also be avoided by the action of give way vessel alone. And only when a stand on ship having observed complete lack of action of giving way vessel for some time and took absolutely no steps to avoid collision she will be held partly to blame.

Rule 17(a)(i), is subject to the qualification that the obligation of the stand on vessel to "keep her course and speed" does not preclude, broadly and neutrally, alterations of course and speed in the ordinary course of navigation. In short, the "course and speed" are the course and speed that the stand-on vessel was going to take for the object she had in view, not the course and speed at any particular moment.

Rule 17(a)(ii)

While it is clear that Rule 17 (a)(ii) permits and 17 (b) requests the stand-on vessel to act, the question which some of deck officers found difficult to answer is: "When to act?" The officer in charge of the stand-on vessel faces a dilemma; he runs the risk of being criticised if he acts too soon or too late. Plainly he must be allowed some latitude in determining precisely when to act.

In Owners of The Ship "Topaz" v Owners of The Ship "Irapua" [2003] EWHC 320 (Admlty), two vessels collided in the Atlantic Ocean; Topaz was proceeding broadly westwards, on a voyage from Mohammedia in Morocco, to Ubu in Brazil and Irapua was proceeding broadly northwards, on a coastal voyage from Necochea in Argentina to Fortaleza, Brazil. Both vessel were making speed of 14 knots. The court held that:

… with the vessels closing, Irapua on a constant bearing and now some 3-4 miles distant, r. 17(a)(ii) applied. It was certainly by now apparent that the give-way vessel was not taking appropriate (or any) action in compliance with the rules.
By the time when the vessels were about three miles apart … Topaz was then obliged to take avoiding action under r. 17(a)(ii).

It is notable that the judge held that notwithstanding that fact that Rule 17(a)(ii) is couched in permissive language, the stand-on vessel Topaz was obliged to act in this particular situations because that was required by good seamanship that the stand-on vessel to take avoiding action before the stage at which Rule 17(b) applies. The judge, however, stressed that permissive language became a binding one only under specific circumstances:

I underline the particular circumstances of the case: the OOW had been observing Irapua for some time; Irapua was not taking any let alone appropriate action to avoid collision; the vessels were now, on a true appreciation, no more than about three miles apart and closing rapidly.

In case The "Lok Vivek" and "Common Venture" [1995] 2 Lloyd’s Rep 230 two vessels collided on crossing courses at an angle of 8 degrees, both making speed of 13 knots. Clarke J. held that Lok Vivek as a stand-on vessel should have made a bold alteration of course to starboard as a matter of good seamanship and as permitted by r 17(a)(ii) of the regulations, when Common Venture was distant between two and three miles. The judge further held that when Common Venture was distant about a mile, Lok Vivek should have put her engines full astern and her wheel hard to starboard in accordance with r 17(b) of the regulations. Whereas the only action the stand-on vessel took was to put the wheel hard to starboard. In failing to take a proper action Lok Vivek as a stand-on vessel was in breach of r 17(b) and was 25 per cent to blame for the collision.

Rule 17(b)

As it was already mentioned with regard to r 17(a)(ii) it must always be a matter of some difficulty for the master of a vessel which has to keep his course and speed with regard to another vessel which has to keep out of her way, to determine when the time has arrived for him to take action, for if he act too soon he may disconcert an action which the other vessel may be about to take to avoid collision. The law therefore, in the beginning of the last century came to recognise, that the precise point at which stand-on vessel must act is necessarily be difficult to determine, and some little latitude has to be allowed to the master in determining this.

In any case, the question whether the time had come to act is largely one of seamanship and depends upon what was the point of time at which a competent seaman in charge of the stand-on vessel ought to have realized that the collision could not be avoided by the actions of the give way vessel alone.

In collision between two very large bulk carriers The "Mineral Dampier" and "Hanjin Madras" [2001] EWCA Civ 1278, the "Mineral Dampier" sank and all 27 of her crew were lost. Collision took place in the East China Sea about 100 miles south of Cheju Island, which is south of Korea. Mineral Dampier, 170,698 tonne dead-weight bulk carrier, was loaded and on a course of 065 deg true at a speed of about 12 knots, Hanjin Madras, 150,977 tonnes dead-weight bulk carrier, was in ballast on a course 140 deg and speed of 11.5 knots. At 5.5 miles apart Mineral Dampier by VHF suggested that the vessels should pass "red to red". Hanjin Madras agreed, but did not alter course at this stage. About three miles apart second VHF conversation took place initiated by Hanjin Madras who told Mineral Dampier to keep her present course and speed. Mineral Dampier replied: "understand your message".

No further VHF conversations took place and no action was undertaken by either side until vessels were about 1.2 miles apart. At this distance Hanjin Madras The Hanjin Madras applied 15 degrees of helm in the first instance and this, in view of experts, would have taken at least half a minute to have any effect. The vessel was in ballast with minimum propeller/rudder immersion and pressure on the rudder. The increase in helm from 15 degrees to hard to starboard would have taken at least a further half a minute to take effect. Therefore more than a minute had elapsed from the beginning of the first alteration of course before appreciable change in the vessels’ heading was achieved. The collision occurred at about 03 30 hours between the starboard bow of Hanjin Madras and the starboard side aft of Mineral Dampier at an angle of about 50 deg leading aft on Mineral Dampier.

It appears that Hanjin Madras was not able to alter substantially to starboard because of the fishing fleet, for some time when distance between vessel was between fife and two miles. Therefore the court held that Mineral Dampier should have maintained her course and speed until it became apparent to her that Hanjin Madras was not taking appropriate action to keep out of her way, which was when distance between vessels was about 1.2 miles at the latest. But Mineral Dampier cannot be blamed for not taking action at or immediately after point when vessels were about two miles apart, because it was not until then that Hanjin Madras could alter substantially to starboard because of the fishing fleet. At para 50, Lord Phillips of Worth Matravers, MR concluded that:

It was only some time after that [point when distance between vessels was about 2 miles] that Mineral Dampier can fairly be blamed for not taking action which she was entitled to take under r 17(a)(ii). As we stated earlier, she is to be blamed for not making a bold alteration of course to starboard. We accept our assessors’ advice that she should have put her wheel hard to starboard at [distance 1.2 miles between vessels] at the latest. It is not suggested that she is to be separately blamed for her hard to port manoeuvre at a very late stage.

Thus, the court held that stand-on vessel was not to be blamed for not taking earlier actions, but only for her fault to act as good seamanship requires and prescribed in r 17(a)(ii) when give way vessel was sufficiently clear off fishing fleet to make avoidance manoeuvre but not taking any action. Secondly, stand-on vessel was guilty that when 1.2 miles apart she did not put her wheel hard to starboard as r 17(b) requests, underlying that at this point it was not simply good seamanship which so required but the express terms of r 17(b).

Avoidance actions, Rule 17(c)

Avoidance actions may be influenced by prevailing circumstances and sufficiency of sea room existing for maneuver of either vessel. The rule as to keeping course and speed, while a perfectly good rule in open waters cannot always be applied in close waters, and each case must depend on its own circumstances. Therefore a stand-on vessel which finds it necessary to manoeuvre is to blame if she deviates from her course more than is necessary to avoid immediate danger.

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