AC34: Rudder ‘Elevators’ new rule will damage ETNZ Design Advantage


Till now I didn´t had many complains on the organization as I totally supported the format , the boats and all the good work done with the AC45 Series. Although of course Artemis accident has triggered some more than reasonable security & safety concerns. The sailors were always the main asset, I demand helmets already on the AC45 even when some claimed that pitchs were the show all wanted to see.

But focusing for a moment on design aspects, and specifically on this key design change proposed by regatta Director Ian Murray,  it is really not fair play for those doing their homework or at least reaching a confidence status like Emirates Team New Zealand has achieved. ETNZ has been my favorite since day 1 just on their design choices and on their out of the box stable flight, add to that they didn´t had any issues in strong heavy winds while digging the bow hard, due to their correct assessment on hull volume to manage all that Wing power and inertia in the floating bareaways or sudden pitchs while airborne.
I remarked 100 times on this pitching, and even Dalton later recognized it the bareaway was a key moment for these boats, and as we all know for every Cat.

Oracle has done a great job too, and they might be even faster, but it is clear that ETNZ has mastered a key design component in a venue with  gusty +20-25knots expected mixed with strong currents, that is not precisely being the faster but gaining control.

ETNZ clearly does not need any rudder elevator comparing their performance to their competitors.
Of course safety it is nr 1 concern right now, but this is also a Design game, and you cannot level the field with a forced rule change. That is simply unacceptable.

Emirates will fill a protest the ACup Jury on this, and if common sense and fair racing prevail they should win the protest, there is no other possible outcome.

Check ETNZ statement at https://emirates-team-new-zealand.americascup.com/news/51291/etnz-to-file-protest-on-ac72-rule-changes

Below some statements from Ian Murray , the last paragraph it is really a joke to be noted at this stage, when we all knew since day one this was to become a key and defining moment of this Cup Edition:  The pitch pole and how to optimize design targeting to avoid it or reduce the chances to happen as Emirates Team New Zealand has done, as remarked with their platform & hulls and their foiling solution.

Ian Murray from Americascup.com
“In simple terms rudder elevators are winglets on the rudder blade which act as control surfaces. The elevators are horizontal and control the pitch of the yacht. As with any rudder, a large surface area provides better control but comes with a drag cost.
My safety recommendations increase the span of the rudders to a minimum of 2.1 metres and stipulate a minimum size of the elevators at .32 square metres, attached to the bottom of the rudder in the most submerged position possible.

The aim is to minimise the chance of a pitch-pole (when the bow of the boat submerges and the stern rises out of the water). The AC72s need control at all times as they are travelling in excess of 40 knots and the hydrodynamic loads when turning the rudders /elevators at speed is substantial.”

Complete article at https://www.americascup.com/en/news/3/news/16127/iain-murray-on-rudder-changes-it-simply-makes-the-boats-safer

2 Responses

  1. Doug says:

    When we first saw the safety recommendations, the thought that one or two performance items had been slipped in, crossed a lot of minds. It is not safety if it is locked in place at the warning signal. In that case it is clearly just a way to delay the setup for the day to the last minute. And the prescribed planform symmetry and area are just obviously a hand brake for the challengers. This should go to the jury and they should hold the design rule as written.

  2. Anonymous says:

    I completely agree and how are they going to know when the starter gun gones off that its locked and not been used while racing because if Oracle gets half the chance they will use it, cant take there word on it,thats worth the paper this rule changes is written on.
    As Im writing this comment I have just heard that the permit from the coast guard has been issued with the rudder rule change going through as part of the 37 recmmendations, just shows you how desprate Ian Murray is to get this rule change for Oracle.I would like to know whats in it for him because it reeks of cheating.
    Cheers,
    Pete.