Forum: The Racing Rules of Sailing

Rule 20 - room to tack at an obstruction...

Douglas Russell
Nationality: United Kingdom of Great Britain and Northern Ireland
I am very clear about the application of rule 20 if two boats are approaching an obstruction. My question is about a group of boats...
In the example below, of RC Lasers racing at Rhu Marina, Scotland, they are all approaching a fixed obstruction - a long pontoon.
If only boat 13 and boat 5 are there, 13 asks 5 for water and they both tack onto port.
Ignore boat 95 for the moment, what is the situation regarding 94 & 28? And what is the situation regarding boat 13 and the boat which is to windward whose sail number is obscured? If 13 meets that boat is he required to tack back onto stbd then once more hail for room once more when approaching the pontoon?
It seems impractical for 13 to hail all five other boats and expect them all to tack...
image.png 758 KB
Created: 21-Sep-23 19:11

Comments

Douglas Russell
Nationality: United Kingdom of Great Britain and Northern Ireland
0
For context, here's where we sail with the image taken from "A". There are specific rules for Model Yacht Racing but the principles are exactly the same as dinghy/yacht racing.
Marina.jpg 7.69 KB
Created: 21-Sep-23 19:21
John Ball
Nationality: Canada
0
05 will need to respond by tacking under 20.2(c) but needs to pass on the hail for room to tack under 20.3 to the undientified boat and 95, 94 and 28.

95 and 28 seem to be far enough back and could hail back " You tack" and stay clear under 20.2(c).

The only functional differences between R 20 and Appendix E is the format of the hail which must include the sail number of the hailing boat and the words 'room' and 'tack'  E1.3(b) and the hail must also comply with E2.1

John
Created: 21-Sep-23 19:43
Bernard Jean-Louis
Nationality: France
0
in model sail the reaction times are without comparison with the full sail. therefore 05 and 95 will have to turn at the announcement of 13 "I tack" but then they will have to respond to the starboard side of the other boats because they will be several lengths from the obstacle. The action will cease as the windward boats will face the obstacle.  (google traduction!!)




Created: 21-Sep-23 20:09
Douglas Russell
Nationality: United Kingdom of Great Britain and Northern Ireland
0
Thanks for the replies. It makes communication easier when all the Skippers are standing beside each other on a pontoon!
Created: 21-Sep-23 20:12
John Thorne
Nationality: United States of America
Certifications:
  • Regional Judge
  • Regional Race Officer
1
O5 and 95 have to give 13 room to tack.  Once 13 has tacked she must keep clear of the other starboard tack boats even if she has to tack again to do so.
Created: 21-Sep-23 21:09
Tim Hohmann
Nationality: United States of America
Certifications:
  • Club Judge
0
From the photo it looks to me like 13 would hail for room to tack from 05, who could pass the hail on to (obscured). Seems like the best option for 05 would be to tack, but (obscured) might be able to allow 13 and 05 to tack and avoid them.

95 can hail for room to tack from 94 but only when she is approaching the obstruction herself - she wouldn't be passing on the hail from 13, it would be 95's hail and would have to comply with 20.1. 94 can pass 95's hail on to 28. 94 and 28 would likely both need to tack.
Created: 21-Sep-24 00:07
P
John Allan
Nationality: Australia
Certifications:
  • National Judge
  • Regional Race Officer
0
Introduction
A lot of this scenario depends on who hails whom.

The particular hailing rules applicable to Radio Sailing (rule E1.3(b)) only require the hail to include the sail number of the hailing boat.  This does not affect which boat’s may be the hailed boat.

Let’s consider the scenario using the diagram below.

In the diagram, the coloured boats correspond to the sail numbers in the OP as follows 
13 = (Y)ellow
95 =(B)lue
05 = (G)reen
Obscured Number = (R)ed
90 = (C)yan
28 = (M)agenta.

Assume that Y hails ‘Water’ or ‘Room to tack’ without specifically addressing the hail to any particular boat.

Rule 20 Multiple Boats.png 109 KB


Summary
A hail for RTT by Y won’t necessarily apply to all the other boats, and even if it does, there will still be some problems.

If R does not tack and responds ‘You Tack’ to Y’s hail, R has no obligation to G, also tacking in response to Y’s hail, unless G passes on Y’s hail.

B and M are in positions that it is unlikely that they will engage with Y, R and R in the RTT manoeuvre.

With G intervening between Y and R, it is unlikely that Y will get into the ‘tack and tack back’ situation, described in Case 101, with R.  For this to apply it is necessary that the hailed boat be advanced on the hailing boat, so that contact would between the hailing boat’s bow and the hailed boats side.

Analysis

B and M and other boats
B and M are to leeward or so far astern of where the action is that they do not need to be further considered.

If it was suggested that B was a hailed boat, she could take the position in respect to a hail from Y, not specifically directed to her, that it was not necessary for her to respond before Y was able to tack, so she was not a hailed boat and had no obligation to respond.

Y and R

Is R a ‘hailed boat’
Case 54 Answer 4 tells us that a hail must be ‘directed towards [a boat]’ and ‘clearly convey that [the hailing boat] requires room to tack’, by inference from the boat towards which the hail is directed.  There can be more than one boat that is a ‘hailed boat’.in respect of one hail.

Case 113 Answer 1 tells us that when there are two boats outside a hailing boat:
  • the boat adjacent to the hailing boat [if it will have to respond before the hailing boat is able to tack] is a ‘hailed boat,  and
  • if the boat that is not adjacent to the hailing boat has heard the hail, and will have to respond before the hailing boat is able to tack she is also a ‘hailed boat’.

It is significantly likely that Y will need room to get past R when Y tacks.  I think it is clear that R needs to respond before C can tack, therefore R is a ‘hailed boat’ and required to respond in accordance with rule 20.2(c).

After Y hails
When Y hails, R might, observing B and G to her leeward, think that, given that these boats will also soon be hailing for RTT, where it will be difficult for her to stand on, she should cut her losses and tack away on Y’s hail.  But supposing she doesn’t and in response to Y’s hail, responds ‘You Tack’, and accepts the obligation to  then give Y room to tack and avoid her.
  • Y should be able to complete her tack to her close hauled course while keeping clear ahead of R but if not, assuming that her tack is not delayed in an unseamanlike way, R is required to give her room to complete her tack and avoid R.
  • When Y reaches her close hauled course, if she has not crossed clear ahead of R, boats will be on a course for collision between R’s bow and Y’s starboard side, with Y required to keep clear by rule 10.  In this scenario, there will not be sufficient space for Y to tack back onto starboard so as to keep clear of R, so the ‘tack and tack back’ provision of Case 101 does not apply, and the only way for boats to avoid contact is for Y to stand on, and R to give her room by bearing away and passing astern of her, thus giving Y the room to avoid R that Y is entitled to.  If Y is not keeping clear of R, she is exonerated because she is sailing within the room to which she is entitled.

Y and G
When Y hails for RTT, G clearly needs to respond and is clearly a hailed boat.

According to the OP G chooses to respond by tacking.

G and R
G can’t tack with R in the position on her hip unless R gives her room.

R is a hailed boat by Y’s hail, if R tacks away, then all is well, but suppose R responds ‘You Tack’

We have an interesting position here:  rule 20.2(c) requires a hailed boat that responds ‘You Tack’ to then give the hailing boat room to tack and avoid her.  Yellow is the hailing boat.

Unless G passes on Y’s hail, G is not a hailing boat and R is not required to give G any room to tack and avoid.

So for G to get the benefit of rule 20 from Red, G needs to pass on Y’s hail to R, whether or not R has already heard Y’s hail or is responding to it..

If G passes on Y’s hail to R and R responds ‘You Tack’, then, presumably R will bear away to leeward of G to give her room, which I would expect would then put R to leeward and astern of Y, so Y should be clear of R.

If G does not pass on Y’s hail and tacks into R, there will be the sound of crunching fibreglass, and R won’t trouble Y.

Y and C
If C hears Y’s hail, she may consider herself a hailed boat, and her logical response would be to respond ‘You Tack’ and in the unlikely event that she engaged with Y, to give her room in accordance with rule 20.2(c).

Otherwise C might take the position in respect to a hail from Y, not specifically directed to her, that it was not necessary for her to respond before Y was able to tack, so she was not a hailed boat and had no obligation to respond.  In that case, when C and Y approach each other only rules 13, 10, 14 and 16 apply.

G and C
If C does not respond to Y’s hail, and G wishes to tack, rather than hail ‘You Tack’ to Y, and G is concerned about C, G needs to hail C for RTT, and rule 20.3 allows her to do this.

If G has passed on Y’s hail, it might also be considered that she had passed it on to C, but C, again, could take the position that it was not necessary for her to respond before G was able to tack, so she was not a hailed boat.  If G doesn’t like this, G can repeat her hail specifically addressed to C, but C’s assessment that she is not involved is looking like a pretty good one.

Is Y required to do a tack and tack back with R?
When Y reaches her close hauled course, if she has not crossed clear ahead of R, boats will be on a course for collision between R’s bow and Y’s starboard side, with Y required to keep clear by rule 10.  In this scenario, there will not be sufficient space for Y to tack back onto starboard so as to keep clear of R, so the ‘tack and tack back’ provision of Case 101 does not apply, and the only way for boats to avoid contact is for Y to stand on, and R to give her room by bearing away and passing astern of her, thus giving Y the room to avoid R that Y is entitled to.  If Y is not keeping clear of R, she is exonerated because she is sailing within the room to which she is entitled.

For tack and tack back to work according to Case 101, the hailed boat has to be advanced on the hailing boat so that the hailing boat is pointing bow to side.
 
Created: 21-Sep-24 02:16
P
John Allan
Nationality: Australia
Certifications:
  • National Judge
  • Regional Race Officer
0
John Thorne,

Remember, a hailed boat only has to give the hailing boat room to tack and avoid if she hails 'You Tack'.  If the hailed boat tacks as soon as possible she has no obligation to give any room.

You might like to look at my comments above about tack and tack back..  It only works if the hailed boat is advanced so that the hailing boat is pointing bow to the hailed boat's beam.

Tim,

How long is a piece of soon?

There is no boat intervening between 95 and 13.  I'd be happy that 95 is an adjacent boat to 13 , who has been hailed for RTT by 13, and is entitled to pass on that hail.  I'd have a lot of difficulty concluding not only that she wasn't a hailed boat, but, given that we are assuming that Y is entitled to hail, that  95 'will not soon need to make a substantial course change to avoid [the obstruction]'.  
Created: 21-Sep-24 03:24
John Christman
Nationality: United States of America
Certifications:
  • Club Race Officer
  • National Judge
  • National Umpire
0
The best and cleanest answer is to delete rule 20 from the book completely.  It is the worst and most broken rule when used, far worse than rule 18.   Just look at John Allan's write up.  What should happen is that Yellow luffs head to wind, followed by the other boats doing what they have to do to keep clear, and then Yellow tacking away from the obstruction when she can do so and keep clear while tacking.  But that is another thread!
Created: 21-Sep-24 15:58
John Ball
Nationality: Canada
0
I disagree with some of John Allan’s analysis – in the post above with his diagram.

While this kind of incident may not occur very much in big boat racing, it happens frequently in RC sailing as we use small bodies of water and the start line is close to shore for visibility and frequently a large fleet will approach a shore line.

When a boat hails for room to tack – it does not come as a surprise – the fleet is heading towards the shore and anticipates that a hail will be coming. As RC boats move around a boat length per second, this whole incident from first hail to the resultant tacks may take just three seconds or so - there is not a lot of time for thinking after the hail - it is more of 'react' - but the boats can see what is happening and developing as they approach the obstruction.

Just looking at the Yellow, Green and Red boats in his diagram, John says

Summary
A hail for RTT by Y won’t necessarily apply to all the other boats, and even if it does, there will still be some problems.

 If R does not tack and responds ‘You Tack’ to Y’s hail, R has no obligation to G, also tacking in response to Y’s hail, unless G passes on Y’s hail.
 

I see this differently. After Yellow hails for room to tack, Green cannot tack because of Red. So even if Red hails ‘You Tack’. Yellow cannot do anything– 20.2(d) applies and Yellow can only tack ‘as soon as possible’ after Green acts. If Red hails ‘You Tack’ Green may also have to hail for room to tack under 20.3 and then Red must do something to respond to Green.

Here is a youtube video of an example from the 2021 UK IOM Nationals at Fleetwood - watch the first minute.

https://www.youtube.com/watch?v=wEdgdv0-dGg

John

Created: 21-Sep-24 17:46
Philip Hubbell
Nationality: United States of America
Certifications:
  • Club Race Officer
  • Judge In Training
0
Have to disagree with JA's claim that "tack and tack back" is limited to a T-bone situation.
IF Y tacks and a bow on bow situation results, Y must still tack back or otherwise keep clear. And, if necessary, a dial-up by R to give Y room to do so makes it all good.
Created: 21-Sep-24 18:02
Russell Beale
Nationality: United Kingdom of Great Britain and Northern Ireland
Certifications:
  • Club Race Officer
  • Regional Umpire
  • National Judge
0
"While this kind of incident may not occur very much in big boat racing,..." John Ball

Actually, it's very common in the Round The Island Race around the Isle of Wight in the UK - hundreds and hundreds of boats on a narrow strip of water all starting at similar times.  And many not listening, unaware of the rules, and/or not in their own boats.....
Created: 21-Sep-24 23:54
John Christman
Nationality: United States of America
Certifications:
  • Club Race Officer
  • National Judge
  • National Umpire
0
It is also very common on the San Francisco City Front when there is a flood tide on any given weekend.
Created: 21-Sep-24 23:59
Douglas Russell
Nationality: United Kingdom of Great Britain and Northern Ireland
0
Sincere thanks for all the replies. When I consulted the rules I was half hoping to find a definition, in boat lengths, about how long one could stay on Port after tacking before having to tack back towards the pontoon - but obviously that isn't the case. I am glad I posted.
Here is where we sail.
Created: 21-Sep-25 09:16
Philip Hubbell
Nationality: United States of America
Certifications:
  • Club Race Officer
  • Judge In Training
0
I recommend downwind starts from A.
Sending the fleet down to a leeward mark or gate will disperse the competitors and make a tight crowd at the pontoon unlikely when they return upwind..
Created: 21-Sep-25 17:17
Tim Hohmann
Nationality: United States of America
Certifications:
  • Club Judge
1
How long is a piece of soon?

Not defined in RRS but Webster says it's "before long."  Does that help ;-)

Created: 21-Sep-25 17:24
Douglas Russell
Nationality: United Kingdom of Great Britain and Northern Ireland
0
A downwind start would indeed prevent the problem of the entire "fleet" sailing towards the pontoon on Stbd en-masse. In the image in my opening post the yellow mark is actually the Stbd end of the line - the port end is a moveable point on the pontoon. For simplicity we simply chuck a windward and leeward mark as far as we can from the pontoon.
If we want more we can use a boat to lay them, or tow them out on a swimming float. The lead weight slides down the line when it and the float are pulled off from the pontoon. A line with two marks and Stbd end bias would reduce congestion...
IMG_1413rev2.jpg 32.3 KB
 
 
Created: 21-Sep-25 18:41
Philip Hubbell
Nationality: United States of America
Certifications:
  • Club Race Officer
  • Judge In Training
0
Or just toss a port passing mark several boat lengths up the course from the starting line on the way to the windward mark.
No one will sail on starboard far enough to encounter the pontoon. The port layline will have been reached first.
Still, that makes a very crowded waypoint so soon after the start. 
People will be yelling "Where the (dickens) are you going?" instead of "Room to tack!"
Created: 21-Sep-25 19:46
P
John Allan
Nationality: Australia
Certifications:
  • National Judge
  • Regional Race Officer
0
John Ball
Said Created: Yesterday 17:46
I disagree with some of John Allan’s analysis – in the post above with his diagram.
...
Just looking at the Yellow, Green and Red boats in his diagram, John says

Summary
A hail for RTT by Y won’t necessarily apply to all the other boats, and even if it does, there will still be some problems.

 If R does not tack and responds ‘You Tack’ to Y’s hail, R has no obligation to G, also tacking in response to Y’s hail, unless G passes on Y’s hail.

 
I see this differently. After Yellow hails for room to tack, Green cannot tack because of Red. So even if Red hails ‘You Tack’. Yellow cannot do anything– 20.2(d) applies and Yellow can only tack ‘as soon as possible’ after Green acts. If Red hails ‘You Tack’ Green may also have to hail for room to tack under 20.3 and then Red must do something to respond to Green.

I can't quite see what John B is disagreeing with.

I'm saying G needs to pass on Y's hail.

John B says G may also have to hail for room to tack under rule 20.2

We seem to be saying the same thing.

Case 113 provides an example where boats are more closely overlapped, with less than a third of a boat between them, and it is 'clear that M and W must both tack in order to give room to L and M does not have room to tack and avoid M.  The critical thing being that W must tack and therefore cannot hail 'You Tack'.

IMHO, in the present scenario where G is barely overlapped on Y, and R is only just overlapped on G, and there is about a boat length between boats, it is not clear that either G or R must tack:  G could choose to duck behind Y, and R could choose to duck behind G.

In my post I briefly canvassed the option for R to tack, and said that if R tacked, the problems posed in the scenario would go away.
Created: 21-Sep-25 21:41
P
John Allan
Nationality: Australia
Certifications:
  • National Judge
  • Regional Race Officer
0
Philip Hubbell
said Created: Yesterday 18:02
Have to disagree with JA's claim that "tack and tack back" is limited to a T-bone situation.
IF Y tacks and a bow on bow situation results, Y must still tack back or otherwise keep clear. And, if necessary, a dial-up by R to give Y room to do so makes it all good.

I think Phil's caught me on a bit of sloppiness.

I said

Is Y required to do a tack and tack back with R?
When Y reaches her close hauled course, if she has not crossed clear ahead of R, boats will be on a course for collision between R’s bow and Y’s starboard side, with Y required to keep clear by rule 10.  In this scenario, there will not be sufficient space for Y to tack back onto starboard so as to keep clear of R, so the ‘tack and tack back’ provision of Case 101 does not apply, and the only way for boats to avoid contact is for Y to stand on, and R to give her room by bearing away and passing astern of her, thus giving Y the room to avoid R that Y is entitled to.  If Y is not keeping clear of R, she is exonerated because she is sailing within the room to which she is entitled.

For tack and tack back to work according to Case 101, the hailed boat has to be advanced on the hailing boat so that the hailing hailed boat is not pointing bow to side.

The last sentence is a non-sequitur to the first.

It should be changed as shown.

Phil, can you agree with that?
Created: 21-Sep-25 21:52
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