For me he is using his body to induce a roll that is not commensurate with the change of course.
Repeated rolling of the boat in connection with a change of course, by making big body
movements followed by a relatively small change of course. - ROCK 6

Al, best if you go attend a Rule 42 training course - too much to write here. Enjoy!

Agreed with Gordon, I would also add wrong timing with mainsail sheet.

Tough to be certain from this camera angle, but I’m seeing repetitive rocks without a commensurate change of course. Always a penalty.

He dumps the main and moves his body out quite aggressively when there’s less drive in the main to counteract and with the exhaust of the more open leech rolling it to weather as well. 

That’s inducing a pendulum rock. 

The steering angle doesn’t change significantly. 

Agree with Gordon. 

Agree with Grant and Gordon.

I'm not a judge and don't know much about this rule (I race multihulls and big boats), but just from a spectating perspective it looks to me like there's an intent to use both body movement and sail movement to unnaturally propel the boat or to bring hull dynamics into the acceleration equation.  At no time does it appear that he's using either to prevent a capsize or a collision.  So I feel like the judge made a proper decision.  But again, my training and experience in this area is virtually nil.

I believe it is as simple as he was fanning the sail Pump 1

Ewan, I have been enforcing rule 42 for about 15 years and have never even heard of a rule 42 training course, much less attended one.  Are they actually a thing in the UK?  Must be nice

I agree with Grant & Gordon.  What also catches my eye is that the rolling being done is much greater than that done by the people around him.  This doesn't make it illegal necessarily, but does make you examine it more closely.  To me, as a judge, I am trying to make sure the competition is fair and let the competitors determine what is ok and what is not.  Make no mistake, clear violations should always be penalized.  Grey area stuff should be based on what the fleet wants and expects, remembering it's their game.

I tend to think about it like the speed you go on the highway.  If everyone is going 100mph, should everyone get a ticket?  Probably not, unless going 100mph is unsafe in those conditions.  It's the guy who is going much faster than the people around them that should get the ticket.

☒☒☒
Ric - I have not ever seen a single specific class on rule 42, although some people are working on parts of it.  There is some guidance material out there for some classes like the Optis and Lasers (attached but not necessarily up to date), but these are always a bit out of date.  The top sailors are always coming up with new techniques that push the boundaries.  Not that they are trying to cheat, but they are working hard to improve, hopefully within the rules.

Thanks to everyone who's responded.

Gordon, Arto, Craig, Grant, Craig, John:

All of you indicated that the sailor here is "using his body to induce a roll that is not commensurate with the change of course."

So, I'm trying to understand here from a good-faith reading of the rules (and not trying to be argumentative):

The sailor here is two things to facilitate his upturn (turn to windward): 1) moving his tiller tip a few centimeters to leeward; and 2) heeling his boat to leeward around 15 degrees.

His tiller isn't in opposition to his leeward heel;  the tiller tip is not to windward. (If his tiller were to windward, that would clearly be illegal since he's not heeling to facilitate steering, and we would not be having this conversation.)

So, yes, there is heel, but the change of course is simply the boat sailing naturally according to physics. RRS 42.3.a states, "A boat may be rolled to facilitate steering." In other words, if you're steering to leeward, you should be able to heel to leeward. If the boat *with tiller to leeward* doesn't turn up enough with that leeward heel, if it's "not commensurate with the change of course", aren't we simply complaining about hydrodynamics? I'm trying to understand why rule compliance requires boats to behave unnaturally...

Digging deeper: the ILCA (Laser) has a tiny rudder. A bigger rudder would help the boat make a "commensurate change of course" for the amount of heel, but obviously would break the ILCA class rules.

42.1 states that "Her crew may adjust the trim of sails and hull, and perform others acts of seamanship" -- but a big rudder movement to make a "commensurate change of course" is slow and therefore could be said not to be an "act of seamanship".

What is seamanship? Maybe there's a case that defines it, but Webster deines it as, "the art or skill of handling, working, and navigating a ship." When we see beginning sailors, their tiller movements are jerky and exaggerated, while expert sailors have smoother and more subtle tiller movements. So, it would seem that big tiller movements are less seamlike, and smaller tiller movements are more seamanlike.

The only way the boat could head up more, for a given amount of heel, would be to push more tiller to leeward. But since bigger rudder movements are less seamanlike, shouldn't a larger change of course ("commensurate with the change of course") put the sailor more at risk of breaking 42.1?
 
It seems like the sailor here is in a Catch-22: either he makes a "commensurate change of course" but risks moving his rudder too much and thus violating 42.1 by not performing an "act of seamanship." Or, he sails in a seamanlike manner (tiller a few centimeters to leeward) but doesn't make a commensurate change of course for his angle of heel. 

What am I missing here?

Ewan, I'd love to take a Rule 42 training course; please let me know where I might be able to find one so I can understand better. ThanksI

Haha!!

Just 'Vang' will do!!

https://www.youtube.com/watch?v=UCo0hSFAWOc

Michael, the commentators seem to agree with you. Listening carefully I hear them call a pump penalty. It is really hard to tell if it is a rock from this camera angle. Being unable to see the full sail is also problematic.

I agree with Gordon, Grant, Michale, John, and the vast majority who agreed with them.
It's a ROCK 5, no doubt whatsoever (and perhaps a PUMP 1, as well [as Michel suggests]).

However, I'll try to be a bit more specific, trying to be helpful by giving Al a reply to his questions, one by one.

>> at what exact instant do you see the violation?
At the start of the clip!
I confess that, immediately afterward, I had a bit of an excitation, with the impression that the rolling was in fact a background rolling (ROCK 3).
However, at 12" it appears that Thompson is evidently inducing that rolling, while his boat continues on a straight course.
This is not permitted (ROCK 5).
At 18" it is evident again.
To note - ROCK 5 states: "A single body movement that is immediately followed by repeated rolling of the boat is prohibited" The key point here is "repeated": as soon as the mast bounces back and starts further rolling, that's "repeated" - so WISTLE AND YELLOW FLAG!
(I agree with Grant, it's difficult to judge the course change from the camera's POW, but the Jury was in a perfect position to assess. I assume they considered it correctly.)


>> 00:02 to 00:04: Nick's tiller moves to leeward as heels to leeward to upturn. That's allowed per Rule 42.3, which states that, "A boat may be rolled to facilitate steering." This is also called ROCK 6
True, but it ends by stating: "The heeling of the boat has to be consistent with the boat's turn." In my view, that is not the case (again, difficult to judge from the camera's POW)


>> 00:005 to 00:07: Nick's mast rocks back and forth while Nick is steering in a straight line. This is allowed under Rule 42; World Sailing calls this ROCK 3 and/or ROCK 4
Wrong! This is NOT allowed under Rule 42 !
You mention ROCK 3 and 4...
ROCK 3 implies that there is a background rolling. I don't see waves to justify that big rolling that Thompson has... Furthermore, look at the other boats. Their rolling is much less than that of Thompson. Comparing the rolling of the fleet to that of the boat you are observing is crucial to determine whether there is a background rolling and to what extent (see John above, as well). In this case, the fleet is (partially) visible only at the end, unfortunately. But that is more than enough...
ROCK 4 starts with the following: "Adopting any static crew position or any static setting of the sails". Nick Thompson's position is far from being static.
Mine is static! As an ILCA 7 Grand Master, I am VERY STATIC in all circumstances... but that is due to my age :-)
In addition, Nick's sail's setting is not static as well.

>> 00:08 to 00:10, 00:14 to 00:16: Nick's tiller again to leeward as he heels to leeward. Again, ROCK 6.
Se what what I wrote before about ROCK 6.

Hope this helps :-)
D 

Thank you Daniele for the taking the time to do a detailed, second-by-second analysis. That's very helpful to those of us who are trying to hone our speed while also sailing in compliance with Rule 42. I won't be able to dig into this for several days, but will do so later. Thanks again.