| Uncle Al's Racing Rules in
Pictures Rules are quoted, then illustrated and explained as seems necessary. Part 2C - At Marks and Obstructions for instant access without scrolling, click on the Rules listed below 18 Passing Marks and Obstructions 18.1 WHEN THIS RULE APPLIES 18.2 GIVING ROOM; KEEPING CLEAR 18.2 giving room; keeping clear: (a) overlapped - basic rule 18.2 giving room; keeping clear: (b) overlapped at the zone 18.2 giving room; keeping clear: (c) not overlapped at the zone 18.2 giving room; keeping clear: (d) changing course to round or pass 18.2 giving room; keeping clear: (e) overlap rights 18.3 TACKING AT A MARK 18.4 GYBING 18.5 PASSING A CONTINUING OBSTRUCTION 19 Room to Tack at an Obstruction 19.1 Room to Tack at an Obstruction: procedure 19.2 Room to Tack at an Obstruction: exceptions This file is also available in PDF format. Click here to view or download. |
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| Above, Søren Jensen (W10212) and Sten
Madsen (W9067) are overlapped on a starboard-tack run. Both have to
keep clear of the close-hauled starboard boat off Sten's bow which is a
leeward boat to both Søren and Sten, and will rank as an
obstruction to Sten. Although Søren has right-of-way over Sten
under rule 11, rule 18 requires that Søren give Sten enough room
to pass the obstruction, i.e. rule 18 (a part of Section C) takes
precedence so that the right-of-way boat (Søren, leeward) must
move out of the way (only) to the extent that the
give way boat (Sten, windward) is able to pass the obstruction
without fear of collision. As soon as the obstruction that caused rule
18 to "kick in" has been passed, everything reverts back to the rules
of the other sections of Part 2. ... |
| 18 ROUNDING AND
PASSING MARKS AND
OBSTRUCTIONS In rule 18, room is room for an inside boat to round or pass between an outside boat and a mark or obstruction, including room to tack or gybe when either is a normal part of the manoeuvre. |
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| This is most typically the situation referred to
by the above pre-amble to rule 18 which amplifies the definition of room
as rule 18 sees it. Geoff Edwards (W9483) and Fred Black
(W7379) are approaching the gybe mark. Geoff is the inside boat (i.e.
he is overlapped on the inside) . Assuming he is entitled to room, that
room will include room to gybe since that gybe will be a normal part of
the rounding manoeuvre. ... |
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| Below, our new kitten (above) - who
loves the computer keyboard - tells us what he thinks of rule 18:
"fffffffffffffffffrrrrrrrrrrrrrrrffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff." Until he can get out and guard SHADES from real mice, he has to make do with this one and occasionally put in his "two paws' worth". ... |
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| This photo illustrates one of the few situations
where rule 18 entitles a boat
to tack as part
of the rounding manoeuvre. Note that Tanya Wharton (W6) is inside boat
and the room that Uncle Al (just to leeward of Tanya) gives her will
have to include room to tack (i.e. to swing her stern wide - so to
speak - as she tacks), since the next leg will be a starboard
tack reach - see 18.2(b) and
the rule 18 pre-amble.
Ironically, if Tanya were clear
ahead here, she would not be immune to the requirements of rule 13 (Tacking), but more on this
later under 18.2(c). ... |
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| A reach-to-reach tack around a mark
(fortunately) happens once per year at best - and it didn't happen
above, either. But it was the closest picture I had, so I added a mark
(just above the lovely Lise Jonasen in W4123) to which Søren
Jonasen (W4123) and Uncle Al with super-crew, Anders Pjetursson, in Whistle
(W9355) will have to sail next. Of course this will require a
tack followed by a close reach on starboard tack. The pre-amble to rule
18 (above) indicates that Søren, the inside
boat, is entitled to room that includes the tacking manoeuvre here. And
again - if Søren were clear ahead, he would ironically not
be entitled to tack as part of his room. ... |
| 18.1 When This Rule Applies Rule 18 applies when boats are about to round or pass a mark they are required to leave on the same side, or an obstruction on the same side, until they have passed it. However, it does not apply (a) at a starting mark surrounded by navigable water or at its anchor line from the time the boats are approaching them to start until they have passed them, or (b) while the boats are on opposite tacks, either on a beat to windward or when the proper course for one of them, but not both, to round or pass the mark or obstruction is to tack. |
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| The above shot from the 1986 Wayfarer Worlds on
Lake Couchiching is the only aerial photo I have on which I can
demonstrate the "two-length zone" defined in the Rules as follows: Two-Length Zone The area around a mark or obstruction within a distance of two hull lengths of the boat nearer to it. Rule 18 begins to apply when boats are "about to" pass or round a mark or obstruction and ends when they have passed it. The term "about to" can lead to disagreements when the outside boat has the right of way (either as leeward or starboard boat). But "about to" is suitably vague since boats of different size and complexity, not to mention the weather conditions and current, will change the distances from the mark (or obstruction) at which one is "about to" round or pass. I myself like to see the moment I stand up to uncleat the spinnaker halyard prior to dousing as a typical moment at which we become "about to round", i.e. the rounding procedure has begun. Obviously that rounding procedure starts earlier if the winds are wild and the boat is planing than when we are dawdling along in a drifter. The number of boats near by would also have an effect. But by the time a boat reaches the "two-length zone", it is definitely about to round or pass and rule 18 applies as necessary. The relevant ISAF quote (Case 84) is "Almost always, a boat two hull lengths from a mark is about to pass it, but this is sometimes so at a greater distance too." ... |
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| In the photo above, Y-Flyer 2546 and W3571 (Bob
Kennedy) may well converge as they near the mark which I have inserted
and
which they had to leave to starboard. There will be a gray area in
which the starboard Y-Flyer may call his rights but Bob (on port) may
feel he is about to round and wants room. If this happens while Bob is
taking down his spinnaker, he would have a strong case that he was "about
to" round. ... |
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| And once rule 18 definitely applies, don’t
forget that if a windward boat rounds
with an inside overlap on leeward, the latter remains the right-of-way
boat (leeward). Above, Flying Scot 4921 is entitled only to room
(the
space needed to make a safe, seamanlike rounding), and not the space
needed for a tactical rounding (wide and close). 4921 has taken far too
much room here and is fouling 3387 to leeward of him. ... |
| "required to leave on the same side" refers to
the possibility that
boats from different race courses may meet at a mark which they pass on
the same side but in opposite directions - one buoys to port, the other
buoys to starboard. Then rule 18 does not apply and it's back to basics
such as rule 10 and 11. ... |
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| I had to dig deep (1998 Wind Bag Regatta) to
find a time when we had what rule 18.1(a) refers
to indirectly: a starting mark not "surrounded by navigable
water". Here, the RC are sitting on the mark at the starboard end of
the line - the shore!! This is the only kind of starting mark at which
rule 18 would apply. At 99.9% of start marks, rule 18 does
not
apply, hence the greeting: "You're barging!!" when someone tries to
squeeze in at the windward end. Allowing buoy room at a start would
create chaos!!! Note though, that last little bit of 18.1(a) which explains that "buoy room" is only suspended when boats are approaching the line to actually start, i.e. you can call for "room" at a start mark with a couple of minutes to go in the countdown (unless you sail in a class where it's common practice to "sit" in your spot on a 100-boat line that early). |
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| This picture covers the only part of 18.1(b) that I have had to use in nearly 50 years of
racing: namely that rule 18 does not apply between boats on opposite
tacks on a beat to windward. Here, Hubert Dauch (W3636) - as the
port-tack boat - is bound to keep clear of both Nick (blue hull) and
Gale (red hull). ... |
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| Quick, now! Is Judd Lather (red spinnaker)
protected by rule 18 at a finish mark??? - Yes, he is. Bob Frick
(the
Wayfarer to leeward of Judd) has to give him room. The only
mark
at
which rule 18 (almost) never applies, is at a start mark. Of course, if
the last leg is a beat, then rule 18 won't apply between boats on
opposite tacks at a finish mark. .... |
| 18.2 Giving Room; Keeping
Clear (a) OVERLAPPED – BASIC RULE When boats are overlapped the outside boat shall give the inside boat room to round or pass the mark or obstruction, and if the inside boat has right of way the outside boat shall also keep clear. Other parts of rule 18 contain exceptions to this rule. |
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| Here, Peter (W286) is the outside boat and has
to give room to the inside boat (the Laser). Not only that, the inside
boat has right of way (leeward) so that Peter must "also keep clear"
- in so many words, the right-of-way inside boat can take as much room
as he likes! Once past the mark, the leeward boat can sail any course
he likes, also. ..... |
| 18.2 Giving Room;
Keeping Clear (b) OVERLAPPED AT THE ZONE If boats were overlapped before either of them reached the two-length zone and the overlap is broken after one of them has reached it, the boat that was on the outside shall continue to give the other boat room. If the outside boat becomes clear astern or overlapped inside the other boat, she is not entitled to room and shall keep clear. |
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| In essence, 18.2(b)
freezes the action and the
rights as the first of a group of overlapped boats reaches the two-length
zone. If at that precise moment you had rights to room (i.e.
you
were overlapped inside the other boat), you
keep those rights through the rounding even if you
then lose the overlap inside the zone. If the
other boat pulls
ahead, he must still give you room. The photo above illustrates another
common possibility: Christian Bovet (W5128) was overlapped inside Paul
Knowlson (W9116) at the moment one or the other of them first reached
the two-length zone. Here, Christian may well go wide of the
mark as he
gybes, tempting Paul to try to cut inside of Christian. An admirable
move - if it works. But 18.2(b) underscores the fact that a boat trying
to
cut in has no rights to room in such a situation: if Christian starts
wide here, but then cuts the mark close with Paul wedged in there, the
latter is out of luck! 720 time!! But if you leave the two-length zone again before rounding, e.g. by going too wide, etc., you have pushed the nautical equivalent of the reset button: your situation must be re-evaluated because any rights you may have had, have - alas - not been saved!! .. |
| 18.2 Giving Room;
Keeping Clear (c) NOT OVERLAPPED AT THE ZONE If a boat was clear ahead at the time she reached the two-length zone, the boat clear astern shall thereafter keep clear. If the boat clear astern becomes overlapped outside the other boat she shall also give the inside boat room. If the boat clear astern becomes overlapped inside the other boat she is not entitled to room. If the boat that was clear ahead passes head to wind, rule 18.2(c) no longer applies and remains inapplicable. |
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18.2(c) is another case of
freezing the action -
in this case with one boat clear ahead of another as she reaches the zone.
Here, John Friis (with Mary in the lime green PFD!) was clear astern of
all the other boats seen in the photo when they reached the zone.
According to 18.2(c) and
regardless of the mess that may soon develop at the mark (off
John's port bow), John must
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| Note however
that the boat which is or was clear
ahead (e.g. Hans Gottschling, W938, in the photo above) is not entitled
to tack as part of its rounding procedure - see the last
sentence of 18.2(c): "If the boat that was clear
ahead
passes head to wind, rule 18.2(c) no longer applies." - which means
that rule 13 does apply
(see ISAF
Case 81)
and if Hans tacks here, he may well foul Peter Rahn (W286). ... |
| 18.2 Giving Room;
Keeping Clear (d) CHANGING COURSE TO ROUND OR PASS When after the starting signal rule 18 applies between two boats and the right-of-way boat is changing course to round or pass a mark, rule 16 does not apply between her and the other boat. |
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| This photo illustrates a situation where rule 18.2(d) might come into play. Under normal
circumstances, rule 16.1 might
well prevent
Uncle Al (leeward boat in
W3854) from changing course towards Hans Gottschling (windward
in W938) because the two boats are so close together that a course
change by Al may not leave Hans enough room
to keep clear. But here rule 18 applies so that, as per 18.2(d), rule
16 does not apply to Al who is free to alter course as he feels is
necessary to round the mark. Hans must be prepared for this and make
sure he is able to keep clear despite any (reasonable!) course change
(such as luffing above close-hauled to "shoot the mark") that Al may
feel is required. |
| 18.2 Giving Room;
Keeping Clear (e) OVERLAP RIGHTS If there is reasonable doubt that a boat obtained or broke an overlap in time, it shall be presumed that she did not. If the outside boat is unable to give room when an overlap begins, rules 18.2(a) and 18.2(b) do not apply. |
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| Rule 18.2(e) points out that it is up to
a boat that
claims there was a last-second change in status - overlap
gained or
broken - to prove that fact. In the picture above, Geoff Edwards
(W9483) ended up getting an overlap inside W7379 (Fred Black) near the
gybe mark. If the question of "buoy room" came to a protest, Geoff
would need to convince the committee that he had indeed established the
overlap in time. If there was reasonable doubt, see
18.2(e) above. Also included in 18.2(e), is the fact that you are not entitled to room if the outside boat is unable to give room at the moment you establish your inside overlap - even before the two-length zone. I still recall a race from the heydays of the June Bug Regatta at Fanshawe in the mid-80's: The wind died right near mark 4 (about 50 metres from the shore) as we ghosted towards it on a late Saturday afternoon run. By the time we got near the mark, there were already 50+ boats of all shapes and sizes wedged in between the mark and the shore - and also on the wrong side of the mark. This was presumably an example of where we could have gotten an inside overlap well before the zone but where the outside boat had no hope of actually giving us the room and so we weren't entitled. ... |
| 18.3 Tacking at a Mark If two boats were approaching a mark on opposite tacks and one of them completes a tack in the two-length zone when the other is fetching the mark, rule 18.2 does not apply. The boat that tacked (a) shall not cause the other boat to sail above close-hauled to avoid her or prevent the other boat from passing the mark, and (b) shall give room if the other boat becomes overlapped inside her, in which case rule 15 does not apply. |
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| Here Nick is about to complete a tack inside the
two-length zone in front of Gale (left) who is
laying the mark.
Thus, rule 18.3 applies. This means Nick will not have the protections
of rule 18.2 such as being entitled to room and freedom from the
restrictions of rule 16 (the
right to change
course as he sees fit to
round the mark). In addition, W864 (Nick) (a) shall not cause the other boat to sail above close-hauled to avoid her or prevent the other boat (Gale) from passing the mark, and (b) shall give room if the other boat becomes overlapped inside her, in which case rule 15 does not apply. Basically, (a) above leaves Nick at the mercy of Gale who can (successfully) protest Nick if Gale feels he had to sail above close-hauled because of Nick's boat being in the way, and(b) above means that Gale can shove his nose in to leeward of Nick unhampered by the restrictions of rule 15 such that Nick probably has no hope in hell of keeping clear. As you can probably tell, our rules makers are trying to discourage us from tacking in traffic near the windward mark. And they have done a good job!! I myself make it a strategic priority to try to avoid tacking in(to) the two-length zone unless there are no other boats near me. ... |
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| This situation actually ended up with a protest.
While Paul Laderoute (W7380) rounded relaxed and in the lead, second
place was a close battle among Heider Funck (W6), Uncle Al (W3854) and
Peter Rahn (upwind of Al). Worried about completing his tack inside the
two-length zone and too close to Peter, Uncle Al is
bearing away behind Peter instead of going for a lee-bow. Al then
tacked as soon as he could do so without hitting Peter. Heider held on
until he had to bear away behind Peter as well - about one boatlength
from the mark. W6 then tacked into the half a boatlength or so
between Peter and Al. This tack likely broke rule 13
(tacking too close) but Heider definitely infringed 18.3 because Al had
to luff up beyond close-hauled and still collided with W6. A
720 was duly done by Heider. ... |
| 18.4 Gybing When an inside overlapped right-of-way boat must gybe at a mark or obstruction to sail her proper course, until she gybes she shall sail no farther from the mark or obstruction than needed to sail that course. |
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| Here, Geoff Edwards (W9483) is "an inside
overlapped
right-of-way boat". Since the next leg is a reach, he "must gybe" to
sail his proper course. Because that is the case, Geoff must make a proper
course rounding, i.e. he is not allowed to
deliberately take
Fred Black (W7379) far past the mark instead of sailing his proper
course. In so many words, Geoff must gybe where he would gybe if no
other boat was near by. It should be noted however, that if the next leg were a very broad reach or a run, then 18.4 would not apply since it addresses only boats who "must" gybe to sail their proper course. ... |
| 18.5 Passing a Continuing
Obstruction While boats are passing a continuing obstruction, rules 18.2(b) and 18.2(c) do not apply. A boat clear astern that obtains an inside overlap is entitled to room to pass between the other boat and the obstruction only if at the moment the overlap begins there is room to do so. If there is not, she is not entitled to room and shall keep clear. |
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| The obvious continuing obstruction that springs
to my mind is a shore along which the boats are sailing - such
as the
east side of Fanshawe Lake above. Here, Roger Shepherd (W7700, the only
Porter-built woodie in North America!) is entitled to establish an
overlap between Jens Biskaborn (W7663) and the continuing obstruction
(the shore) only if there is room to do so. Remember that room
involves sailing in a seamanlike manner, so that if Roger should run
aground or hit a tree while establishing his overlap, he is not
entitled to room. ... |
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| A less obvious continuing obstruction is a
right-of-way boat sailing along beside you. Above, the Laser (leeward
boat) ranks as a continuing obstruction to Peter (black hull)
who in turn is a continuing obstruction to the Y-Flyer, etc. As Len
(W6732) overtakes, he could go between Bob (W3571) and the Y-Flyer, or
possibly between Peter and the Laser and then ask the windward boat for
room to keep clear of the leeward boat. But Len cannot wedge in between
Peter and the Y-Flyer while they remain this close together since there
is not "room
to pass between
the other boat (the Y-Flyer) and the obstruction
(Peter in the black boat)". ... |
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| Here, Steen
Schubert and Keld Forchhammer in their new Abbott Mk III, W10249, can
move in between Mogens Just and Søren Jensen
(the continuing obstruction) since there is lots of room to do so but
... |
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| ... here, on a start line, Hazel Hewitt (teal-coloured
shirt) and Peter Ayres (blue hull) are out of luck. There
is definitely not enough room for anything to
squeeze into the front row here! ... |
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19
ROOM TO TACK AT AN OBSTRUCTION |
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| Here, Roger (W7700) is just completing a tack to
starboard and will now be sailing along just to windward and astern
of Brian (W9235). If Brian is worried about hitting an
obstruction (the shore), but is likely to foul Roger by tacking, rule
19.1 lets Brian ask Roger for "room to tack". Brian must do this on the early side because
In the photo above, the following sequence of events might typically occur:
Note that rule 19 applies only where the boat asking for "room to tack" cannot tack and subsequently keep clear of the other boat, i.e. if Brian (9235 above) can tack and then bear away to keep clear of the starboard boat (7700), Brian must do so without invoking rule 19. ... |
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| In the photo above on the left, 1305 (starboard)
is an
obstruction to 1131 who is on port tack. Therefore 1131 would have had
the
right to hail 171 for "room to tack", had he done so well before the
moment captured here. Having not hailed, 1131 is now blissfully
sailing into a situation where he is sure to foul the starboard boat
(1305) since he's left it too late to bear away, or the boat to
windward of him (171) by doing a crash tack (see photo on right) to
avoid 1305. There are often two possibilities for the leeward boat who can hail for room to tack, or pass astern of Starboard. If Leeward opts to call for "room to tack", then Windward cannot claim room to pass astern of Starboard, since rule 19.2 states: "When rule 19.1 applies, rule 18 does not." Note however, that unless Leeward has to make "a substantial course change" to pass astern of Starboard, rule 19.1 (Room to Tack) is not available to him. If, on the other hand, Leeward chooses to pass behind Starboard, rule 19.1 is not being applied. Therefore Leeward must - under rule 18 - allow Windward (AY171 in this case) room to pass astern of Starboard, also. ... |
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19 ROOM
TO TACK AT AN OBSTRUCTION |
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| This picture tells the story of why 19.1 cannot
be allowed to apply at a starting mark, even if that mark (the RC boat
in this case) is large enough to qualify as an obstruction.
Imagine the
absolute mess that would be created if Peter Rahn (286) for instance,
got wedged in
towards the RC boat and could now request room to tack!!! |
|
Rules
in Pictures index
Definitions
Defintions PDFI have also made PDF's of the five items below - for those who want to print the material or work off line. These PDF's will not have the many links included in the on-line version, however. Part 2A Part 2A PDF Part 2B Part 2B PDF Part 2C Part 2C PDF Part 2D + penalty turns 2D PDF Photo-based Rules Quiz - 1 Photo-based Rules Quiz - 2 |