Crossing Vessels

Yealm

Well-known member
Joined
13 Apr 2017
Messages
5,337
Visit site
Quick question - if crossing vessels (under power) and you're the give way vessel, does it matter which way you turn ?
This teaching guide says either port or starboard is fine (it seems to slightly favour to port).

Rule description

I thought I remember differently - that convention is to turn to starboard (although that doesn't seem to be part of Rule 15).

Grateful for clarification !
 

john_morris_uk

Well-known member
Joined
3 Jul 2002
Messages
27,210
Location
At sea somewhere.
yachtserendipity.wordpress.com
There are very good reasons for turning to starboard if you’re stand on and find the other vessel isn’t complying. “(c) A power-driven vessel which takes action in a crossing situation in accordance with sub-paragraph (a)(ii) of this Rule to avoid collision with another power-driven vessel shall, if the circumstances of the case admit, not alter course to port for a vessel on her own port side.”

lit you’re give way it’s often quicker and easier to alter to starboard and pass behind the other vessel. A turn to port means you have to rely on speed differential to keep clear. You end up parallel to the other vessel either waiting to get far enough ahead to avoid breaking the rule about “trying to avoid passing close in front of another vessel” or you have to slow down to allow the other vessel to pull ahead so you can resume course and pass behind him. In the latter case you’d have even better off altering to starboard in the first place.
 

johnalison

Well-known member
Joined
14 Feb 2007
Messages
38,735
Location
Essex
Visit site
As jm says, you will normally be approaching the stand-on vessel’s port side and, unless you are a lot faster than them, turning to pass astern is the only practical course. There may be occasions such as when the other vessel has restricted ability to manoeuvre when you may need to turn the other way, but generally the situation will make the best solution obvious.
 

Yealm

Well-known member
Joined
13 Apr 2017
Messages
5,337
Visit site
Many thanks.

Also, could I ask - is there anything in Colregs that defines at what separation distance the rules apply ? I think AIS can work at over 20 miles away, visibility maybe 5 miles away ?

Secondly, what is a sensible rule of thumb CPA distance that is reassuring, ie in the context of crossing shipping lanes in a small vessel ?
 

Never Grumble

Well-known member
Joined
29 Sep 2019
Messages
865
Location
England
Visit site
At what distance do the rules apply. Depends on the circumstances, nature of the vessels, where you are (harbour, mid solent or mid channel). I certainly wouldn't be worrying about a ship 20 miles away. The best way to get a feel is to get out there and gain some experience, with others who know what they are doing if at all possible.

Buy yourself a Seamans Guide to the Rule of the Road. It's what's given to all seaman officers in the RN on joining (or was) has pictures to learn by. Try one of the second hand bookshops abebooks.co.uk and you can get one for £3.
 
Last edited:

superheat6k

Well-known member
Joined
10 Jan 2012
Messages
6,700
Location
South Coast
Visit site
The danger of a port manoeuvre is if the stand on vessel doesn't think the give way vessel is taking sufficient / any action and makes a sudden manoeuvre to avoid, as he is required by the rules so to do.

So the risk here is he (stand on) turns late stbd quite correctly to avoid what he perceives is lack of proper attention / manoeuvre by the give way vessel, when at the same time, and by now quite close, the give way vessel makes his alteration to port - the result being they meet in the middle, and likely with little space left for either to take further avoiding action.

This situation is entirely avoided if the rule of thumb I was taught when learning to sail where any avoidance manoeuvre should be "Early and in Good Time", indeed such a prudent manoeuvre often means the alteration can be quite subtle in regard to the base track, but of course should always be clear to the vessel being avoided so your intentions are understood.

What has always amazed me is the number of folk who seem to deliberately maneouvre to create an otherwise non-existant risk of collision, and this seems especially the case with those who feel it is some form of absolute requirement to pass Port to Port, even when if both vessels simply plied on the resultant Stbd to Stbd crossing would have been perfectly safe and suitably distanced.
 

Gary Fox

N/A
Joined
31 Oct 2020
Messages
2,027
Visit site
..What has always amazed me is the number of folk who seem to deliberately maneouvre to create an otherwise non-existant risk of collision, and this seems especially the case with those who feel it is some form of absolute requirement to pass Port to Port, even when if both vessels simply plied on the resultant Stbd to Stbd crossing would have been perfectly safe and suitably distanced.
Yes, the Elbe No. 5 collision was a good example.
 
Last edited:

mainsail1

Well-known member
Joined
27 May 2008
Messages
2,369
Location
Returned to South Coast from West Coast of Scotlan
Visit site
Is that practicable when crossing Channel TSS?
Yes, I can tell you from experience on the bridge of larger ships I want give way yachts under power to take action at least a mile away or I will feel very uncomfortable. Remember, I am probably doing that mile in 3 or 4 minutes and if I was give way vessel I would probably have altered course at 2 or even 3 miles.
 

Yealm

Well-known member
Joined
13 Apr 2017
Messages
5,337
Visit site
Yes, I can tell you from experience on the bridge of larger ships I want give way yachts under power to take action at least a mile away or I will feel very uncomfortable. Remember, I am probably doing that mile in 3 or 4 minutes and if I was give way vessel I would probably have altered course at 2 or even 3 miles.
Presumably thought if CPA >1 mile then noone needs make a course change ?
 

RAI

Well-known member
Joined
13 Jun 2006
Messages
15,683
Location
Ayamonte
Visit site
Yes, I can tell you from experience on the bridge of larger ships I want give way yachts under power to take action at least a mile away or I will feel very uncomfortable. Remember, I am probably doing that mile in 3 or 4 minutes and if I was give way vessel I would probably have altered course at 2 or even 3 miles.
I love AIS. Actually observing a professional change course to give me a CPA>1 nm when I'm the stand-on vessel. Very comforting.
And I can do the same for him when I'm giving way.
 
  • Like
Reactions: GHA
Top