My support and defence of the existing rules is that they require such a ship to stand-on and, in my opinion, this is preferable to requiring her to reach across the bow of the other ship in what history has shown to be a death run. The danger of what was then called the port-helm/starboard-rudder rule for both ships in an encounter was ablely demonstrated by Captain P H Colomb in his books entitled The Law of Port Helm (co-authored with Captain Brent in 1866) and The Danger of the Modern Rule of the Road at Sea (1885). These led to the adoption at the Washington Conference of 1889 of the rule that every vessel which is directed to keep out of the way of another shall avoid crossing ahead of the other. This rule was drastically watered down in 1972 when it was restricted so as to apply only to vessels in sight of one another.

The non-application of the prohibition on altering to pass ahead and the prohibition on altering to port for vessels meeting in restricted visibility amounted to the re-introduction for such vessels of the old port-helm/starboard-rudder rule with all its attendant dangers, ineffectiveness and inefficiencies. These dangers were mitigated by the cautions and precautions prescribed by Rule 19 for vessels in restricted visibility. However, in so far as mariners regard Rule 19 as a licence for both vessels to alter course to starboard these dangers remain as no rule can be made which escapes the geometry of the situation.

The original port-helm/starboard-rudder rule was introduced in 1840 before sidelights had been adopted. It was impossible at that time to tell how the other vessel was heading or to differentiate one vessel from the other. When regulation sidelights were introduced the rule with all its dangers was abolished, at least for vessels in sight of one another.

Rule 19 for vessels in restricted visibility was introduced in 1972 in somewhat similar circumstances of necessity to those of 1840. Radar, by modern standards, was unreliable and it was quite likely that one ship would not know of the presence of the other. More importantly, information from radar could only be obtained by painstaking plotting and alterations of course were not quickly detected.

These circumstances have now changed. We have 24/7 radar with Arpa and AIS. The danger of one vessel’s alteration of course unknowingly cancelling out the other vessel’s alteration of course are gone, whether in sight of one another or in restricted visibility. In these days of high speed craft, there are greater differences in the speed of ships and in their manoeuvrability than ever before. There is a compelling demand from captains to have rules which would enable them to exploit the full capabilities of their craft and their ARPA and AIS collision avoidance equipment. The case for dual action rules is undeniable.

‘Simon sez everyone turn to the right’ may be great fun on the dance floor, but it is not the way to conduct craft on the oceans of the world. A simple and elegant dual action rule is called for. There is such a rule: namely Colomb’s rule which has been described in the letters pages of Seaways in July 2003. It is amazing that a 19th century admiral thought of a rule which is the perfect rule of the road for the 21st century. The rule or axiom is not articulated by Colomb in either of the books he published but is bequeathed to us in an article he wrote in Naval Science in 1872. It might be described as ‘Colomb’s lost rule’ and it is the claim to fame of this letter-writer that the rule in all its glory has been rediscovered through painstaking research. Though Colomb described the rule or axiom in geometrical terms its underlying dynamic is the difference in the speed of the ships involved in the encounter. Its adoption would reduce the rule of the road to one or two simple rules and would make the rules compatible with existing traffic separation schemes. Above all it would allow Arpa and AIS to be exploited to the full.

Coming from Finisterre, heading for Ireland or the St. George Channel area, I have to encounter many ships on my starboard bow at sharp angles coming from Ushant TSS. I am not of the generation that looks first at the radar or Arpa, but the kind that simply changes course a few degrees to starboard and gets the southbound vessel on my portside.

If there were no visualisation but only a radar available to provide me with such information, I would tend to do the same, although, some plotting would not do any harm in that event. However, a ship in my sight, on my starboard bow at a near counter-course, makes me alter course to starboard by definition and let the vessel pass on my port.

Looking through the bridge windows, I often (I mean often) see a ship change its heading to his port. This makes me change more to starboard, even at right angles or more to my original course. There is no impediment to that in this particular sea area. Five minutes or so later, the other vessel corrects his move and alters then his course to his starboard and we pass each other on our port. This elapsed time is a clear indication that the beggar on the other vessel only looks at his radar! He apparently does not use the crystal clear windows, but Windows-XP.

This ‘to port’ alteration of heading is a misinterpretation of seamanship and a violation of the rules.

There certainly is a generation gap, which cannot be bridged and should never be approved.

Arpa should not be the primary information if visualisation is readily available.

I was at the Rotterdam Nautical College more than 30 years ago. My teachers repeatedly told us not to change course to port as we would certainly meet each other in an unpleasant way. I still believe they are right.

Nicholas Cooper’s advice is to keep your ship safe and if you are not comfortable with the situation the other ship is forcing you into, then get out of it. He advises you to get out with a broad alteration to starboard; to run away from the other ship and show her your port quarter; to force her to take your stern as she ought to have done in the first place.

This advice to you from Captain Cooper is entirely consistent with the 1972 rules for avoiding collisions at sea. However, the problem is that in this situation you are applying the rules to avoid close quarters and risk of collision rather than an actual collision. In the majority of these cases the original CPA position of the other ship will lie to starboard of your ship. In all likelihood, your alteration to starboard will simply take you to this original CPA position of the other ship just in time to meet her there.

The scenario described by Captain Cooper demonstrates very cogently why mathematical solutions to the collision problem, and the collision avoidance diagrams which they have spawned, do not work at sea. There is no panacea in altering course to starboard. There is only one natural rule for avoiding collision at sea:

Never ever, if you are taking action to either avoid collision or risk of collision, cross the path of the other ship.

Own vessel, as depicted in the question, looks deceptively large. Obviously the plan is not to scale or the ship would be over a mile long. This has the effect of making the channel look narrow and may have led to some confusion.

My conclusion, therefore, is that the vessel is not in any way constrained by her draft. If own ship is displaying constrained by draft signals, the question should state that. The author appears to make the assumption that the reader would know this, whereas I feel that the majority of respondents did not make this assumption.

The options open to own ship are to ‘alter to starboard’ or to ‘reduce speed’. The crossing vessel should ‘stand on with caution’. I assume that the purpose of this question was to address the term ‘not impede’. As far as I can remember, this term has always been a problem: it is one of the grey areas of the rules.

My own solution to this problem is as follows:

• Rule 3: Delete paragraph (h) the definition of a vessel constrained by her draft.
• Rule 8: delete paragraph (f)
• Rule 9: replace the term ‘not impede’ with ‘keep out of the way of’
• Rule 10: as Rule 9 above
• Rule 18: delete paragraph (d)
• Rule 28: delete the rule

The term ‘not impede’ has been a problem every since it appeared in the rules and there have been various attempts to clarify its meaning. All these have filed. Rule 8 (f) was one such attempt. This was written in legal jargon by lawyers for lawyers with little for the OOW who might have to decode it. I can remember, when taking my orals, being told not to worry about this term. ‘It’s controversial and the examiner will steer clear of it’. Sure enough, they were right.

If the intention with the Colregs survey was to stir up debate, then it surely has done that. If the experts cannot agree on these things then what chance has the officer on watch? As appears to be the case in the results so far, the prudent mariner will observe what he perceives to be good seamanship, judgement etc.

We must remember that the vast majority of collisions are caused by vessels taking action that was meant to prevent collision. In this respect the rules have failed miserably. Non measurable or quantifiable terms such as ‘not impede’ and ‘if in doubt’ ought to be relayed to the history books. What we need is a clearly defined, indisputable and easily understood set of rules.

In fairness to those who responded it should be pointed out that this particular scenario is open to different interpretations so that many of the combined answers given should not be regarded as incorrect.

Scenario 2 shows own ship proceeding along a channel 3.5 miles wide with one vessel crossing from starboard to port so as to involve risk of collision. It is stated that own ship can only navigate within the channel. No information is given about the size and type of own ship, the target ship is said to be small. Although the channel is said to be 3.5 miles wide the diagram shows channel width to be only about 2.5 x own ship length and own ship to be about a ship length away from the starboard edge of the channel.

The question arises as to whether a channel 3.5 miles wide should be regarded as a narrow channel. I am not aware of any passage of more than 2 miles in width being regarded as 'narrow' for the purposes of the Colregs. In a recent US case the passage between buoys at the entrance to Delaware Bay, approximately 1.2 miles wide was held not to be a narrow channel.

If this is not a narrow channel, the small target vessel would not be required by Rule 9(b) to avoid impeding the passage of own ship. The next question is whether own ship is constrained by her draught and exhibiting the appropriate signals; if so target ship is required by Rule 18(d)(i) to avoid impeding the safe passage of own ship. The signals prescribed by Rule 28 are not mandatory and should only be shown if the vessel is severely restricted in her ability to deviate from the course she is following. Would own ship be justified in showing such signals in a channel 3.5 miles wide?

The majority of responses showed slow down or stop as best action for own ship.

In such a crossing situation altering course may be more effective and more readily apparent to the other vessel than reducing speed but the diagram shows own ship near to the starboard edge of the channel and it may even be assumed that own ship is severely restricted in her ability to deviate from her course. It is therefore not surprising that, in the circumstances, the majority of those responding opted for a reduction of speed by own ship. A reduction of speed would be in accordance with the Rules and should not be regarded as incorrect.

The N1 Colregs survey has been useful in identifying issues to address but care must be taken to avoid stretching things too far in order to make a strong case for improvement.

The only point I partly disagree with in the article is the expected reaction from a small ship going to cross a channel while on a collision course with a large vessel on her port side and following the channel, this as exposed in Figure 1 In his summing up, the author wrote:

'Target ship will obey Rule 8(f) and either slow down, stop or alter to starboard. She cannot go to port, as this would be in direct contravention of Rule 8(f)(i).' This is theoretically correct, but the OOW on the large vessel will be aware of the correct intention of that small vessel not to impede much sooner if she comes early enough to port and heads to point astern of the large vessel. This is also what I recommended to yachtmen some years ago. As long as the bow of the small ship is directed accross the path of the large vessel, the OOW will always wonder about any change of speed. A drastic manoeuvre to starboard is also good if there is really a risk that the large vessel would come to starboard, but it will also make the manoeuvre much longer, preventing the large vessel moving to starboard for another crossing vessel.

I fully concur with Roger Syms when he wrote in the final paragraph:

'The inescapable conclusion is that the whole concenpt of "not to impede" regardless of its apparent logic or how well deliberated and drafted, simply does not appear to work in practice.'

To quote from STCW, section A-VIII Part 3-1 – Principles to be observed in keeping a navigational watch: ‘The officer in charge of the navigational watch is the master’s representative and is primarily responsible at all times for the safe navigation of the ship and for complying with the International Regulations for Preventing Collisions at Sea, 1972.’

From many incidents I have studied, as reported in the maritime press, it seems clear that STCW is not adherred to by all contracting governments. For other contracting governments it acts merely as a management tool in order to reduce the required level of education for obtaining a certificate of competency.

It is my opinion that as long as navigators repeatedly succeed in colliding with the wreck of the Tricolor, for example, and as long as the stream of MARS reports on near encounters and collisions continue, then what is really lacking on the bridge is discipline. We don’t need a change in the Colregs themselves. What we urgently need is a positive change in the professional attitude of many watchkeeping officers from all the varying nations. Personally I can live pretty well with the existing Colregs. What I won’t accept is VHF calls like: ‘What are your intentions?’ and ‘Ship on my…side’.

Would it not be an improvement to make it an international requirement that all seagoing deck officers will have to pass an examination on the Colregs again, every five years? When every watchkeeping officer has an acceptable knowledge of the existing Colregs at the ready, then we might start thinking again about a change. To change the existing Colregs before such an acceptable general level of knowledge has been obtained, would mean that out there at sea we are going to have at least two different versions in place.