You are hereBlogs / webmaster's blog / Mark Rounding - Who is in the right?

Mark Rounding - Who is in the right?

webmaster's picture

By webmaster - Posted on 04 June 2017

On Saturday June 3 2017 fleet racing, in Flying Scot fleet Race 3 there was an incident which occurred during the final leeward mark rounding. This is a description and analysis of the situation.

Comments on this analysis are encouraged. The most complicated part of the racing rules is when boats meet at a turning mark. It is a fluid and dynamic situation with little time to think. Early preparation and crew communication can avoid collisions and rules violations. Nonetheless, even among professional and highly trained sailors collisions and rules infractions still do occur.

Here is the situation:

Yellow and Blue were on a run to the leeward mark. Neither boat flew spinnakers. At position 2 Yellow entered the zone just ahead of Blue. Yellow approached the mark closely and gybed sharply around the mark. In the mean time, Blue swung wide and cut inside the mark as Yellow passed it. Yellow bore off slightly to avoid Blue at position 4. Yellow came up sharply and trimmed aggressively for the upwind race to the finish. In the mean time, Blue's skipper briefly lost the mainsheet and Blue slipped downwind while Yellow was coming up, resulting in a minor collision.

Were there any rules violations? If so by who? If so how could the violations be exonerated?


Rules potentially involved


When boats are on the same tack and overlapped, a windward boat shall keep clear of a leeward boat.


A boat shall avoid contact with another boat if reasonably possible. However, a right-of-way boat or one entitled to room or mark-room (a) need not act to avoid contact until it is clear that the other boat is not keeping clear or giving room or mark-room, and (b) shall be exonerated if she breaks this rule and the contact does not cause damage or injury.

Rule 18: Mark Room

Rule 18.1 When Rule 18 Applies

Rule 18 applies between boats when they are required to leave a mark on the same side and at least one of them is in the zone

Rule 18.2 Giving Mark Room

(a) When boats are overlapped the outside boat shall give the inside boat mark-room, unless rule 18.2(b) applies. (b) If boats are overlapped when the first of them reaches the zone,the outside boat at that moment shall thereafter give the inside boat mark-room. If a boat is clear ahead when she reaches the zone, the boat clear astern at that moment shall thereafter give her mark-room. (c) When a boat is required to give mark-room by rule 18.2(b), (1) she shall continue to do so even if later an overlap is broken or a new overlap begins; (2) if she becomes overlapped inside the boat entitled to mark-room, she shall also give that boat room to sail her proper course while they remain overlapped. (d) Rules 18.2(b) and (c) cease to apply when the boat entitled to mark-room has been given that mark-room, or if she passes head to wind or leaves the zone.

Rule 18.4 Gybing

When an inside overlapped right-of-way boat must gybe at a mark to sail her proper course, until she gybes she shall sail no farther from the mark than needed to sail that course. Rule 18.4 does not apply at a gate mark.


Rule 44.1 Taking a Penalty

A boat may take a Two-Turns Penalty when she may have broken one or more rules of Part 2 in an incident while racing...

Rule 44.2 One-Turn and Two-Turns Penalties

After getting well clear of other boats as soon after the incident as possible, a boat takes a One-Turn or Two-Turns Penalty by promptly making the required number of turns in the same direction, each turn including one tack and one gybe...

Glenn's Conclusions

Rule 11 applies. This is both at position 2 just before the boats enter the zone. There is no violation of Rule 11 before they enter the zone. Rule 11 was violated by Blue at final position where the 2 boats collide.

Rule 14 applies. Yellow complies with this rule by avoiding the collision at position 4. The rule is violated at the final position. Yellow violates rule 14 at this point but is exonerated by 14a and 14b. Blue violates Rule 14 at the final position.

Rule 18-1, 2, 4 applies. Specifically, Blue violated 18-2b and 18-2c2 when Yellow bore off just after the rounding to avoid Blue.

In summary, Blue's actions when she cut inside the mark and at the point of collision are a violations of the rules. They can be exonerated by performing a two-turn penalty.

So what do you think? Your comments and analysis are encouraged.

CraigNSC's picture

When Slower is Faster

Published on June 6th, 2017 by Editor-->

David Dellenbaugh shares in the US Sailing blog how slowing down can put you ahead in a race.

The goal of a sailboat race is to beat your competitors to the finish line, so going full speed ahead is usually the best strategy. However, there are a few places on the race course where sailing slower may actually be faster. The leeward mark is one of them.

At most leeward marks you end up rounding right behind another boat. This competitor and her wind shadow present a critical challenge. If you make too wide a rounding, for example, you’ll end up in her bad air, which is definitely slow.

When you exit from the leeward mark, you want to be at least slightly to windward of the centerline of the boat ahead so you have the option to keep sailing straight ahead in relatively clear air. In order to do this you must:

• Be 100% ready to race upwind before your bow gets to the leeward mark;
• Swing wide before the mark so you can pass very close to it (you should be able to reach out and touch it);
• Be going fast (faster than your close-hauled speed) when you get to the mark so you can use this speed to pinch up slightly above the boat ahead.

The best tactic to accomplish all this may be to slow down before the mark. If you keep going fast, you’ll end up right on the transom of the boat ahead. This may seem like a good rounding, but it has two problems:

1) If you misjudge your speed or if the other boat slows unexpectedly, you could hit them in the transom. Often the only way to avoid fouling is to bear off below them (which puts you right in their bad air).
2) The closer you are to the boat ahead, the more likely you are to be in (or fall into) their wind shadow.

One good way to avoid both problems is to round the mark with a bigger gap between you and the boat ahead. I recommend at least half a boat length from your bow to the other boat’s transom. In certain boats and conditions, it may be smart to leave a full boat length between you and the boat ahead.

There are several advantages to creating this gap.

First, it reduces the risk of catching up to the boat ahead, which means you won’t have to avoid them by bearing off into their bad air. Second, it allows you to accelerate as you approach the mark (rather than slow down which is often the case when you’re afraid of catching up to the other boat). And third, the gap helps you avoid the wind shadow of the boat ahead. There is almost always clearer air a boat length behind a boat than right on her transom.

In most cases faster is better, but don’t be afraid to slow down when this tactic gives you more options and better control of your situation.

Learn more tips on how to improve your racing performance from Dave Dellenbaugh’s Speed & Smarts.

Source: US Sailing

sails149's picture

I see blue as being the keep clear boat and in the wrong as it did not allow yellow room to round in a seaman like manner. 

Blue should have kept behind yellow. In these situations if blue is going faster and cannot slow down he should have immediately tacked when it became clear he 'had' to go inside yellow , taking care not to foul boats behind trying to round the mark



"Yellow bore off slightly to avoid Blue at position 4." If this is true, then I believe Blue should withdraw.

I expect the collision afterwards was "minor", again Winward boat must keep clear. Strike-two for Blue.

Dan Reasoner

rschuss's picture

I feel yellow did not properly perform her gybe, Rule 18.4, and created the situation that blue took advangtage of. Had yellow committed to the gybe and the proper course, Rule 14, 14a, blue may not have had the opportunity to get inside, or there would been a crash at the mark.  The crash at position 4 is the responsibility of blue, Rule 11, obviously.

Russell Schuss

blough's picture

And, for the record, the truly Blue FS was not involved, although I've plowed into plenty of sterns at leeward marks over the years.

The authors changed the identities of the boats for the purpose of discussion, I am  sure. 


blough's picture

 Better tactic for Blue might have been to try to Slow Down before the mark, enough to ensure it would stay clear astern throughout the rounding.  Then, i f Blue executed a tight rounding,  she could attain an  inside lane and avoid Yellow's bad air, at least for awhile, probably long enough to control the timing of the next tack.  It is getting harder to "sneak inside" anyone, because everyone is getting better at Mark roundings. 

In  my view, Blue definitely violated windward-leeward rule after the rounding. If yellow's swerve to leeward during the rounding was specifically to avoid Blue and was necessary to avoid collision, then Blue also failed to give Mark room. Luckily only a 720 is required to exonerate, not a 1440, since the two violations were part of one incident.

P.S. My cheap tablet either doesn't handle sailing terms  well or has a perverse sense of changed many words, most notably changing "roundings" to "do I dings"!!!!


CraigNSC's picture

Had a similar rounding the week before.  Skippers need to understand that a inside boat needs mark room.  Even if the inside boats starts to show an opening it may close back up, or it could.  My case I started to head back up and there was a boat sneeking in between me and the mark, now closing down my inside room.  Definition is when is one completed a mark rounding.  Rules for 2017-2020 define mark room as 1) sail to the mark, 2) leave the mark on its required side and 3) round as necessary to sail the course.

I agree Blue should not have tried to get inside Yellow was not on course to the next mark (sail the course).