The flight control gremlins crept into Alinghi Red Bull Racing’s session on Friday afternoon out in Barcelona and although a nosedive at high-speed downwind and a ripped jib was the result, the crash was telegraphed from almost the off.
Running two different foil profiles on the AC75 with the Emirates Team New Zealand flat foil on starboard and the anhedral NYYC American Magic foil on port, has been a challenge for the Swiss since BoatZero was launched. Both have very different characteristics on the exit of either a tack or a gybe and with BoatZero being very much a bow-down trim seeker since the cockpit modifications, there’s a big wrestling match going on for the Flight Controllers to keep her flying and maintain rudder immersion.
In the early part of the session, BoatZero was bow-dipping through almost every tack and then downwind, especially when transitioning from the anhedral port foil to the flat starboard foil, the tendency for the boat to rise and then the bow to dip was pronounced. Preceding the nosedive, several gybes were caught on camera and the rudder - which is the legacy American Magic rudder due to the fact that the ETNZ rudder is still in the repair shop after the rudder tower structural failure at the end of March - was dicing oh so close with breaking the surface.
The Swiss got away with it for a while but on their sixth gybe of the day, going from starboard gybe to port gybe, the inevitable happened and immediately after exit, BoatZero flew just a smidgen too high on the ETNZ foil and as the bow came down, the rudder broke the surface, all grip was lost and the sailors were mere passengers into a nosedive crash. The J3 jib ripped through impact just aft of the tack and tore pretty much up to the level of immersion as BoatZero came to a stop and corkscrewed up into wind, broaching, with the crew doing a great job to stop any potential for capsize.
Unfortunately, one cyclor, Nico Stahlberg, was injured in the nosedive and was quickly transferred back to base with minor injuries and Nicolas Rolaz, the newly promoted member of the Alinghi Red Bull Racing Driving Group, jumped onboard and took over in the port aft cyclor pod for the remainder of the session. The sacrificial wind wand was collected by the recon team, floating in the water, and after the tech team had jumped on and checked through everything (and also fitting a replacement wind wand in double-quick time), BoatZero was back and flying but far more cautiously than the early part of the session.
An afternoon of two halves, with the J4 set, the balance of the boat evened out as the wind built to 12-14 knots and Maxime Bachelin and Nicolas Charbonnier put BoatZero impressively around a laid course with Yves Detrey and Bryan Mettraux keeping flight low and controlled both upwind and downwind with the bow clear. A huge improvement on the pre-nosedive antics and Alinghi Red Bull racing completed an entertaining and productive day of training that saw some 38 manoeuvres with a 78% success rate of foil-to-foil or touch & go being recorded.
Speaking about the nosedive afterwards, Bryan Mettraux was matter-of-fact in his assessment saying: “Yeah, so we were exiting of a gybe and just flying too high at the exit and we lost the rudder so the boat go down really quickly and, yeah, we had one of our grinders that is a bit injured but the news (about him) is pretty good… I think all the crew did a good job then to make him in a safe position.”
The tightrope between on and off in the AC75 and the difficulties of running alternate and vastly different foil profiles at full scale was acutely shown today in Barcelona. Alinghi Red Bull Racing bounced back quickly though, changed the dynamic profile and pitch and put in a solid day on the water of some five hours and over 50 nautical miles covered. No sailing this weekend, the Swiss will be back at it next week.