The term "Impeding" Explained

[calamitys38]

I posted this on the Scuttlebut several months ago (and then got into an argument with a couple of yotties who took the simile absolutely literally and ranted on about stopping distances and two lanes of traffic etc (i.e. complete rubbish) but who then went on to think that beacuse they were in a sailing boat my expanation and the existance of Rule 10 implied they had no rights at all!) I consequetly gave up and left them too it. However, hopefully the more astute members of this board will appreciate what I'm trying to get across as to what the the term "avoid Impeding" actually means, without taking the example too literally.

"Just re-read the post a while back regarding giving way in a TSS and a comment was made by one poster that the phrase "avoid impeding the passage of" was one of the most missunderstood parts of the Rules. I quite agree and for what its worth - here's one of the best explanations I've ever heard (as explained to me by an MCA Examiner) and one I teach my students:

Consider two cars approaching a traffic junction. Your traffic light is green and the other cars traffic light is red. You obviously are the "stand on" car and the other one is required to "give way". No problems so far.

However, if the the other car was an emergency vehicle with "blues and twos" going, although his traffic light is red and he is therefore the "give way" car, presumably you would allow the emergency vehicle through and therefore would "not impede his passage". If you did not do this and continued through your green light, as you are perfectly entitled to do as the emergency vehicles light was red, they would have to give way as the normal Highway Code dictates, but you would be a complete f u k w i t.

This simile is exactly the same at sea. You are in a Power Driven Vessel (PDV) and have another on your Port side crossing - it is the Give Way vessel and you are the Stand On vessel. However, if the other vessel was Constrained by her Draft, you are required not to impede her passage as per Rule 18 and would hopefully take early action to allow her passage. The other vessel however, still remains the Give Way vessel.

Same again in a TSS. A sailing vessel should not impede the passage of a PDV follwoing a Traffic Lane. However, if the sailing Vessel does impede the PDVs passage, then the normal steering and sailing rules continue to apply and the PDV should give way to the Sailing Vessel - but like the simile with the emergency vehicle above - you would still be a complete f u k w i t to make the PDV alter her course to do this"

Hope this helps?

 

[epervier]

Ah, but you've forgotten the most important element that lots of people fail to use, motor and sail, ....................common sense.

 

[tinkicker0]

I much prefer the law of self preservation.

 

[icepatrol]

give way old chap

have to agree with the previous. but i take your point and wondered if anything dire was to happen how would it look in a court of law ?
the difference with on the road and in the drink is possibly we have a little bit more room and time to take avoiding action. road vehicles dont always have the room to go anywhere.
i have certainly come across quite a few "yachty`s" who wanted to enforce their "assumed" right of way, but on the whole most take the sensible route and we simply avoid each other like the plague.
good luck...lol.

 

[jfm]

I don't think that is a correct explanation of "impede" at all. There's much to criticise the colregs about in terms of their capricious use of the the word "impede", but your explanation doesn't clear up the meaning of the term. The constrained by draft vessel is the stand on vessel under the colregs; it isn't correct to say the pdv is stand on but then is required not to impede in a manner analogous to a green-lighted car letting a red-lighted blues n twos vehicle go first. All imho

 

[calamitys38]

I don't think that is a correct explanation of "impede" at all. There's much to criticise the colregs about in terms of their capricious use of the the word "impede", but your explanation doesn't clear up the meaning of the term. The constrained by draft vessel is the stand on vessel under the colregs; it isn't correct to say the pdv is stand on but then is required not to impede in a manner analogous to a green-lighted car letting a red-lighted blues n twos vehicle go first. All imho

Sorry. I'm afraid the CBD vessel on your port side IS the Give way vessel. BUT, you are required NOT tO IMPEDE its passage or safe passge. That means by displaying its CBD lights/shapes, it is asking you to treat it in the same way as you would an emergency vehicle with blues and two going who is facing a Red light if yours is on Green.

It really is the long and short of it. If you are on a PDV and another PDV is crossing on your Port Side, you are Stand On and it is Give Way. The ONLY exceptions are Fishing Vessels, Sailing Vessels and Vessels NUC or RAM. This is why it only says in Rule 18 that you should avoid IMPEDING a vessel CBD and not KEEP OUT OF THE WAY as per the other parts of Rule 18. Therefore, my explanation of how to READ what does AVOID IMPEDING means stands.

By the way, I'm not shouting in the above when I am writing in Capitols, just emphasising various points.

 

[jfm]

Sorry. I'm afraid the CBD vessel on your port side IS the Give way vessel. BUT, you are required NOT tO IMPEDE its passage or safe passge. That means by displaying its CBD lights/shapes, it is asking you to treat it in the same way as you would an emergency vehicle with blues and two going who is facing a Red light if yours is on Green.

It really is the long and short of it. If you are on a PDV and another PDV is crossing on your Port Side, you are Stand On and it is Give Way. The ONLY exceptions are Fishing Vessels, Sailing Vessels and Vessels NUC or RAM. This is why it only says in Rule 18 that you should avoid IMPEDING a vessel CBD and not KEEP OUT OF THE WAY as per the other parts of Rule 18. Therefore, my explanation of how to READ what does AVOID IMPEDING means stands.

By the way, I'm not shouting in the above when I am writing in Capitols, just emphasising various points.

Thanks for the further expl. I'll take another look at the rules and come back to you. I see the point you're making. What you say is a good illustration of something I was banging on about on this forum a while ago - that there are concepts like "give way", "not impede", "keep out of the way of" etc, and are they all meant to mean the same thing? If they mean different things, what are the differences? The car that lets the ambulance go on a red light is acting purely out of courtesy and altruism, whereas colregs positively order a non RAM boat not to impede a RAM boat, so the analogy doesn't quite work at that level. But as to your basic point I get ewhat you're saying and will re-read the rules tomorrow and revert! Thanks

 

[timbartlett]

FWIW, I think the terms "Give way" and "Not impede" are defined in the colregs, but not very clearly signposted.
Give Way is in Rule 16: it means "take early and substantial action to keep well clear".
not impede is in Rule 8f: it means "take early action to allow sufficient sea room for the safe passage of the other vessel.

Unfortunately, no matter how good the intentions of 8f, I think it is typical of the more recent additions to the colregs, in that it is so badly written as to be almost incomprehensible.

The guidance note that it replaced was much better: it said, IIRC, something along the lines of "navigate in such a way as to avoid the development of a risk of collision".
In my book, I've interpreted that as meaning "as the skipper of a small craft, you are expected to take avoiding action sufficiently early that the question of whether there is a risk of collision or which is the give-way vessel simply does not arise"

But it has the same big snag as in Rule 17: what seems "early" to the chap who is looking at the situation with a height of eye of two metres above the waterline seems very different to someone looking down on the same situation from a height of twenty or thirty metres.

 

[Bilgediver]

But it has the same big snag as in Rule 17: what seems "early" to the chap who is looking at the situation with a height of eye of two metres above the waterline seems very different to someone looking down on the same situation from a height of twenty or thirty metres.

Especially if he also has 10,000 containers on his foredeck stacked 8 stories high!!!!!!

 

[Spookyfella]

When it comes down to the final analysis, it's not who's right, it's who's left !

 

[Salty John]

I'm with jfm on this one. I can't see how defining the term "impeding" clarifies anything except at the most basic level - i.e. what does impede mean. In the term " shall not impede" it's the "shall not" bit that's important, not the definition of impede. Impede, as we all know, means 'get in the way of'. "Shall not get in the way of" seems pretty clear.
Introducing analogies involving ambulances and traffic lights serves only to confuse, not clarify, in my opinion.
The pecking order of give way/stand on vessels is absolutely clear. Why not simply adhere to that? How you adhere to that rule is explained in the three parts of rule 8f.
Seemples.

 

[calamitys38]

I'm with jfm on this one. I can't see how defining the term "impeding" clarifies anything except at the most basic level - i.e. what does impede mean. In the term " shall not impede" it's the "shall not" bit that's important, not the definition of impede. Impede, as we all know, means 'get in the way of'. "Shall not get in the way of" seems pretty clear.
Introducing analogies involving ambulances and traffic lights serves only to confuse, not clarify, in my opinion.
The pecking order of give way/stand on vessels is absolutely clear. Why not simply adhere to that? How you adhere to that rule is explained in the three parts of rule 8f.
Seemples.

OK Salty John

Whilst I don't totally dissagree with you, here is a typical MCA question given at the Orals Exam:-

Q: You are on a PDV heading North in the correct lane of a TSS. You see a Sailing vessel, crossing fom Port to Starboard. The Sailing vessel is 2 Points to Port at a range of 4 Miles. The bearing is steady and the range is closing. Who is the Give Way vessel and what actions would you take?

A: I am the Give Way vessel, but the sailing vessel should avoid impeding my passage and should take early action to avoid impeding my passage. However, if she continues on her course and speed, a risk of collision exists and as the Give Way vessel, I will alter course accordingly (probably to Port and go round her stern as she is on my Port side and I am the Give Way vessel.)

It would be assumed to be safe to go to Port as it would the duty of the PDV to Give Way to the Sailing Vessel and certainly in a TSS. There is unlikely to be the room to make broad alteration to starboard, or even consider taking a round turn out. Slowing down is impractical on a large commercial vessel, so you are left with only one option.

My explanantion stems from the fact that the words "shall not impede" exist and it is to try and give an understanding of how these should be interpreted that I wrote the original post. "Shall keep out of the way of" etc is a fairly straightforward command, but "shall not impede" is not. If they were menat to mean the same, then the Rules would have said the same - they don't, and I would suggest that my explanation (without being taken too literally) provides an easy to understand simile for understanding what is meant by "shall not impede"!!

Happy sailing

 

[splosh]

Well phrased Calamity s38!

In your explanation and further: A LARGE Commercial Vessel i.e a Container Ship travelling along in a TSS like the Dover Strait's with sand banks either side would be constrained by its draught in its ability to manouvere, to which common sense would also tell you not to IMPEDE its passage.

So many times have I witnessed what you are trying to clear up.
Yes, colregs do apply - but also peoples brains and sensibility should apply to the application.
SOLAS.

 

[piratos]

Traffic separation

A little story for the real life. In Germany I was running at displacementspeed right side of the TSS. I was overtaken by a german coastguarvessel (customs !) and turned to port crossing the TSS by a right angle. NOW the vessel from the coastguard turned 180° and came on a collission course to me, so I turned to stb to avoid a collission. This ofcourse brought me to run on the wrong side of the TSS, and consequently I was stopped by the coastguard, claiming me for running on the wrong side. After some discussions I told them that they were wrong: They made the 180°turn bringing them in a collission course. I was forced to take action to avoid the collission. There were no other vessels within a mile.

 

[DAKA]

I posted this on the Scuttlebut several months ago (and then got into an argument with a couple of yotties who took the simile absolutely literally and ranted on about stopping distances and two lanes of traffic etc (i.e. complete rubbish) but who then went on to think that beacuse they were in a sailing boat my expanation and the existance of Rule 10 implied they had no rights at all!) I consequetly gave up and left them too it. However, hopefully the more astute members of this board will appreciate what I'm trying to get across as to what the the term "avoid Impeding" actually means, without taking the example too literally.

"Just re-read the post a while back regarding giving way in a TSS and a comment was made by one poster that the phrase "avoid impeding the passage of" was one of the most missunderstood parts of the Rules. I quite agree and for what its worth - here's one of the best explanations I've ever heard (as explained to me by an MCA Examiner) and one I teach my students:

Consider two cars approaching a traffic junction. Your traffic light is green and the other cars traffic light is red. You obviously are the "stand on" car and the other one is required to "give way". No problems so far.

However, if the the other car was an emergency vehicle with "blues and twos" going, although his traffic light is red and he is therefore the "give way" car, presumably you would allow the emergency vehicle through and therefore would "not impede his passage". If you did not do this and continued through your green light, as you are perfectly entitled to do as the emergency vehicles light was red, they would have to give way as the normal Highway Code dictates, but you would be a complete f u k w i t.

This simile is exactly the same at sea. You are in a Power Driven Vessel (PDV) and have another on your Port side crossing - it is the Give Way vessel and you are the Stand On vessel. However, if the other vessel was Constrained by her Draft, you are required not to impede her passage as per Rule 18 and would hopefully take early action to allow her passage. The other vessel however, still remains the Give Way vessel.

Same again in a TSS. A sailing vessel should not impede the passage of a PDV follwoing a Traffic Lane. However, if the sailing Vessel does impede the PDVs passage, then the normal steering and sailing rules continue to apply and the PDV should give way to the Sailing Vessel - but like the simile with the emergency vehicle above - you would still be a complete f u k w i t to make the PDV alter her course to do this"

Hope this helps?

That helps a lot, good post.

I have frequently been concerned about the correct way to cross the TSS, or other channels in the solent.

Easy to give way if you are doing 30 knots by holding course longer and then altering course to go astern before they have time to alter course, but for slower displacement speeds it is more complex, in that the ship cant be certain I am going to give way so they are forced to take avoiding action before I give way (both vessels have an equal duty to avoid a collision) thus I have impeded them even though I intended to give way.

Interesting, if I understand correctly, the slower I go the sooner I have to take avoiding action in order to be certain I am not going to impeded them.

 

[Salty John]

OK, Calamitys38
I fully understand the point you are seeking to clarify with the ambulance/traffic light analogy - I merely expressed an opinion that such an analogy might tend to confuse further, rather than clarify, the point.
I have always stressed the importance of Rule 2B, "the rule of general prudence", to cover these situations but you clearly feel a more specific clarification is required on this point. Fair enough.

 

[icepatrol]

pecking order

could i just ask a question regarding who would have priority in this pecking order in the dark. forgive my ignorance on this but i just wondered how do you identify the vessel in the dark to know she has right of way.

 

[Salty John]

By the lights the vessel is showing. There are specific combinations of lights for each type of vessel and its circumstances - fishing, constrained by draught, restricted in ability to manoeuvre etc.

 

[calamitys38]

could i just ask a question regarding who would have priority in this pecking order in the dark. forgive my ignorance on this but i just wondered how do you identify the vessel in the dark to know she has right of way.

A PDV underway shall show a masthead light (shall show two if more than 50m in length, but a PDV less than 50m may show two as well), sidelights and a sternlight.

A vessel CBD (in addition to the above) will show three all round red lights in a vertical line where best seen and by day - a cylinder.

A Sailing vessel just shows sidelights and a sternlight - unless it turns its engine on and then it bocomes a PDV. Additionally, a saling vessel may show a an all round Red over an all round Green at or near the top of the mast as well as sidelights and a sternlight

A Fishing vessel, when making way, shall show an all round red over an all round white, sidelights and sternlight and by day two cones apex together

A Trawler, when making way, shall show an all round green over an all round white, sidelights and a sternlight and by day, two cones apex togther.

A Vessl NUC, when making way, shall show two all round red lights in a vertcal line where best seen, sidelights and a sternlight and by day, two black balls in a vertical line where best seen. When not making way, swithch off sidelights and sternlight. Shape doesn't change whether making way or not.

A Vessel RAM when making way shall show masthead light(s), sidelights and a sternlight as well as three all round lights in a vertical line in the order Red, White, Red where best seen. By day, three shapes being Ball, Diamond, Ball. Ram vessels then get a bit complicated as a minesweeper shows different lights altogther and Dredgers (or vessels engaged in underwater operations) show additional lights and shapes to indicate the side the danger exists.

Hope this briefly answers your query.

Happy sailing

PS Please note the distinction between being underway and making way. Underway is NOT attached to the shore, at anchor or aground - it has NOTHING to do with moving through the water - which is making way.

 

[jfm]

Calam
Thnaks for explaining. I see your point. I gotta say though, this just adds to the list of faults in the colregs imho. It's kinda like the rules of the (tamac) road saying when a car approaches a green traffic light he must stnad on, and when a car approaches red light he must give way, and when the red-light car is blues-n-twosing the green light car must not impede, but still has right of way.

Blimey - one rule is saying stand on and you have right of way, and another is saying you must keep out of the way of. I mean, 17ai positively says hold your course if you are stand on, no choice. Yet 8fi says get out of the way of (say) an RAM boat. And 8fii sort of says the normal give way rules apply to the RAM vessel so it is the give way boat, yet the boat to which it gives way to must not impede it.

What a sodding mess. The rules should state quite clearly who has to get out of whose way. Not say A is stand on, B is giveway, and then say (with no hierarchical ranking of these conflicting rules) that A isn't allowed to impede B. Sheesh!

Thanks for pointing this out though Calam!