"Safe passing distance"

[captain58sailin]

I cannot count the times, I have heard the open radio call, "ship off my port bow" or what ever with no position given only a relative position, usually in a place where they could be addressing anyone. General rule of thumb for me is 2 nm CPA if possible and 1nm if not. Under most all situations I will avoid passing ahead of the other vessel, unless radio contact is made and a definite passing or crossing arrangement is made. Most large ship's speed are deceptive due to their size, and one doesn't realize how fast they are going until it's too late. I also subscribe to the "tonnage rule".

[leftbrainstuff]

Safe distance is a subjective measure. If I was to quantify it I would state it as > 0 feet or meters.

One person might think 6 inches is a safe distance while another might think 30 feet is too close.

As an engineer we also state thresholds and tolerances so a safe distance might also include manoeuvering room and consider the consequence of risks such as a wind shift or engine shutdown. We use analyses such as failure mode effect and criticality models to consider a wide range of failures.

There is no single answer to the question 'what is a safe distance. There are many answers.

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[monte]

I think often large commercial shipping and ferry companies have minimum CPA requirements to be adhered to. Often it's 1M, maybe 2M in open ocean, obviously a lot less in harbours and at slower speed. If there is a close quarters situation and the captain hasn't adhered to company policy they have a good scapegoat to lay the blame on which is fair enough.
A few weeks ago we had a collision course with a ship. We were stand on vessel in open water so I contacted the ship via VHF to discuss passing with 30 mins to go. He replied and told us he would give us a wide berth. I thanked him and continued sailing as he altered course by a few degrees and passed 1/4 M astern of us. Not really what I would consider a wide berth, but safe enough as we both knew each other's intentions. This was a small to medium size ship that likely didn't have much in the way of corporate ship handling policy. Smaller fishing vessels much less so...

[Suijin]

Originally Posted by FamilyVan

I've discussed this on another thread but don't recall the details.
The answer is often complicated. I'll try to answer but my answer will not be comprehensive.
-there is frequently a language barrier. The oow (probably not the Captain or even the chief mate). He may not feel comfortable speaking English.
- a Junior Officer in general may not be comfortable speaking on the radio. Especially if there's a very top down command structure.
-rules. The use of VHF as a method of collision avoidance isn't identified in the international ColRegs (it is however in Canadian and American modifications).
-they may not identify you as a threat as they have much better tracking capabilities (this is a little rude of them in this case- but thats life).
-Some may not like yachtsman very much due to past encounters. Yes- stereo typing isn't very nice, but many sailors are comfortable with not being very nice.

Thanks, that is interesting to know. I always try on 13 as well but that never seems to make a difference. In sum, I should just deal with it and not be peeved. Good enough.

[Dockhead]

Originally Posted by FamilyVan

I've discussed this on another thread but don't recall the details.
The answer is often complicated. I'll try to answer but my answer will not be comprehensive.
-there is frequently a language barrier. The oow (probably not the Captain or even the chief mate). He may not feel comfortable speaking English.
- a Junior Officer in general may not be comfortable speaking on the radio. Especially if there's a very top down command structure.
-rules. The use of VHF as a method of collision avoidance isn't identified in the international ColRegs (it is however in Canadian and American modifications).
-they may not identify you as a threat as they have much better tracking capabilities (this is a little rude of them in this case- but thats life).
-Some may not like yachtsman very much due to past encounters. Yes- stereo typing isn't very nice, but many sailors are comfortable with not being very nice.

Sent from my SGH-I547C using Cruisers Sailing Forum mobile app

I have discussed this question many times with commercial mariners.

There seem to be two different schools of thought among commercial mariners:

1. Follow the bloody Colregs and leave off the inane chattering on VHF.

2. I'm glad to talk to you and talk through the crossing, so no one gets confused, which is dangerous.


One thing I can say for sure: discussing a crossing on VHF is no substitute for following and, for God's sake knowing, the Colregs

So, "just call him up on VHF" is not a correct collision avoidance procedure.

There is an official MCA memorandum discouraging the use of VHF in collision avoidance. There are several reasons for it -- risk of talking to the wrong ship (which can have disastrous consequences); distraction from the serious work load of understanding the crossing and planning safe maneuvers; completely unnecessary if everyone just follows the rules.

Nevertheless, I do agree that a VHF call can be useful, IF you have AIS and can therefore positively identify the ship you want to talk to ("calling big ship in position x and y on course z" is bogus and almost useless; use only in a desperate emergency; ships almost never answer this kind of call anyway). When I am the stand-on vessel, and I see a dangerous CPA with a ship which I would have expected to have maneuvered by now, I like to call up just to know what the guy's intentions are. If he doesn't answer, then that's another piece of evidence that he's not taking action, which can give you the right to maneuver yourself. If he does answer, than I can find out what he's thinking and we can agree what to do.

If you are the stand-on vessel and it's too late for you to maneuver yourself (risk of collision already exists) and too early for this right to be restored (not yet clear that he's not taking action; still plenty of time for him to do it), but for whatever reason you want to maneuver yourself without waiting, then a VHF call is the only seamanlike way to do it -- so that you can agree the maneuver and be sure that you aren't screwing up his plan. There may be some circumstances (running out of sea room; you're hard on the wind and hard to change course; etc.) where it's preferable to do this rather than wait for the time when the Colregs give you the right to initiate maneuvers yourself without agreeing it with the other bridge.

[captain58sailin]

Commercial marine companies do not establish minimum CPAs, Master's of the vessels do, and it is in their standing orders and night orders.

[ranger58sb]

Originally Posted by Suijin

Thanks, that is interesting to know. I always try on 13 as well but that never seems to make a difference. In sum, I should just deal with it and not be peeved. Good enough.

When I've hailed ships by name (from AIS info) here in the Chesapeake, it's almost always the pilot who answers, and I don't remember ever not being answered at all. Calling tugs, also by name, has always worked well for me.


When we're trolling in the early Spring, I usually go out of my way to let them know I'm aware of their course... and that I'm taking steps to avoid their course... 'cause I'm pretty sure our track would look a little goofy to them on their systems.

-Chris

[Dockhead]

Originally Posted by ranger42c

When we're trolling in the early Spring, I usually go out of my way to let them know I'm aware of their course... and that I'm taking steps to avoid their course... 'cause I'm pretty sure our track would look a little goofy to them on their systems.

Good on you for that!

A crossing with a fishing vessel with gear in the water can be a tough thing because you don't know where they will go next, whether they will turn in front of you, or whether they even have gear in the water (the day shape for this seems to be permanently welded in place on all French and Dutch F/Vs )

It's especially tough at night when you can't really see the gear.

Even worse, many F/V's turn off their AIS transmitters when fishing (to guard their trade secrets, I guess). Crossing the North Sea at night last May, I had many encounters and thanked God a number of times for my radar set. Not too many amateurs in those tough waters, however, so the crews always switched on AIS and deck lights as I got closer, but always later than what I considered a comfortable decision point.

In other waters, F/Vs are less predictable, and so I treat them the way FamilyVan treats WAFIs -- as dangerous and unpredictable, and I steer a wide berth around them, taking action before a risk of collision arises so that's it's allowed by the Colregs.

[Lodesman]

If he's trolling, he's not a fishing vessel.

[Dockhead]

Originally Posted by Lodesman

If he's trolling, he's not a fishing vessel.

For purposes of determining whether you are give-way or not, naturally:

"(d) The term “vessel engaged in fishing” means any vessel fishing with nets, lines, trawls or other fishing apparatus which restrict manoeuvrability, but does not include a vessel fishing with trolling lines or other fishing apparatus which do not restrict manoeuvrability"


But you still want to take extra care in a crossing with any vessel with any kind of gear in the water, wouldn't you agree? It certainly influences how close you will be willing to pass behind! It also says a lot about what the crew is concentrating on at the moment!

[ecamphunk]

Originally Posted by SV Liberty

Better yet, use your radio after looking at your AIS (receiver only, not transponder - that's another topic) to determine the name of the vessel you are hailing.

SV Liberty, what do you mean by "AIS (receiver only, not transponder - that's another topic)"?

[valhalla360]

They don't give specific distances because any number they give you can be shown to be wrong depending on the circumstances.
- If you say they can't get within 5 miles, it's impractical as soon as you reach confined waters. On the river system, we've passed within 30' of a tow...because the alternative was to run aground.
- If you say, 200yds away is fine, it can be pretty scary if it's a large ship at speed. We saw a big sports fisher (probably 80-100') cut that close behind a freighter. He launched off the first wave and completely buried the bow in the second. It looked like he hit a wall. We called and the captain claimed no one was hurt but at the least there had to have been some damage. Luckily we were probably 2-3times as far away and being smaller and slower just rode up and down the waves. Unfortunately, it was in a channel and we couldn't get much further away.

[Seasick Steve]

..yes - I was about to point out that use of the VHF for collision avoidance is very definitely NOT recommended in the Rules. There are, I believe (cos I was told so by an Instructor whom I trusted), cases of VHF-induced collisions. There may be confusion of identuty for example.

[zeehag]

i stay away.
if you can see whites of eyes yer way too close
is a lot easier to avoid shipping than one would believe.
in general you will notbe close to these big guys unless you sail in big shipping harbors, in which case, turn OFF your bs electronix and sail using eyeballs and brain. you would be surprised at and by how easy that is to do.

is kinda like messing with spiders.

[rognvald]

I have always sailed and abided by the "ASA" rules: Assume Stupidity Always!" If you follow these rules, you will always be at a "safe passing distance." However, if you are the stand on vessel in a channel, you might be in for a surprise. Last year while entering our harbor, a 50 foot Searay passed to starboard by <10 feet with <10 feet to the concrete rubble breakwater on his starboard. He was going well beyond the no wake speed limit and threw a 2-3 foot wave as he passed. I immediately called him on the VHF radio using his vessel's name and chastised him for what he had just done. He said he was a licensed captain and was legally passing me. I asked him why he did not signal his intentions with a horn before passing, why he was sailing at an unsafe speed and why he had passed so closely--throwing a wake in a very restricted channel. He said he had to get his guests back to the dock and that he was running late. The dock was less than 50 yards away. I probably should have reported him to the CG but when I saw his Wayne Cochran Blue Eyed Soul Brother hairstyle, I gave him a pass . Safe passing distance? ASA! http://youtu.be/w5_GstlPL64