Please select your home edition
Edition
Savvy Navvy 2024

America's Cup: Bang! New video of Foil Arm Destruction Testing

by Richard Gladwell, Sail-World.com/nz 22 May 2019 07:40 PDT 23 May 2019
Final destruction test- AC75 foil arms - Persico Marine - May 2019 © America's Cup Media

A video has been released by America's Cup which shows the two destruction tests of the carbon foil arms for the AC75.

The tests were undertaken at Persico Marine, who will build Italian America's Cup Challenger of Record Luna Rossa's two AC75s.

The first test of the carbon foil arm failed earlier than expected in September 2018, triggering rumours about the state of the project in which Emirates Team New Zealand was charged with developing the foil arm mechanism, while Luna Rossa was responsible for the design and build of the carbon arm. Both the foil arm and the raising mechanism are one design parts and are supplied to the other teams as standard equipment.

In the first round of testing the foil got through to the second phase of the test before breaking with a sound like an exploding bomb.

"At 88% of the maximum test load in the first test, we heard some noise from the arm," recalled Luna Rossa's Davide Tagliapietra. "We got a warning from the acoustic emission device."

"We decided to skip that test and pass onto the next one, because there were areas that we could better understand in the next test plan."

During the second phase of the first test the board failed unexpectedly with a noise like a bomb exploding as the test rig crumpled.

"We have no confidence to carry on with this architecture," said Tagliapietra - in the biggest understatement so far in the 36th America's Cup.

The competing teams then decided to collaborate, and Auckland based composite design team Pure Design and Engineering team was also included in the new project team.

Fast forward eight months to mid-May 2019, and the combined engineering group reassembles at Persico.

"This type of boat has never been done before," said ETNZ designer Guillaume Verdier - recognised as the world's leading high performance yacht designer.

"This is the first time we have introduced this new kind of architecture. We want to make sure it works," the French designer added.

"It's not very often that you get the opportunity to test something to this level, and have this amount of information available," explained Andrew Corkery of Pure Design and Engineering.

"But there is also the uncertainty that you are putting something into the test rig that has never been tested before. You never know what can go wrong," he added.

Verdier says the design team are treading a fine line between weight and strength in the carbon foil.

"It has to be light to be able to take off on the foils in light winds. We can't afford to produce something that is too heavy and will not allow us to foil as soon as possible," he added.

Like a countdown for a rocket launch, the load cylinder is called.

"Three tonnes, four tonnes," starts the load call, as the engineers watch various screens that show the S-shaped arm and the loads that are being experienced at various points of the test foil.

The new foil design passed all of the preliminary tests before going into the final test.

"This last test is one way, there is no way back. Breaking this arm is going beyond the usual engineering screening that we normally do on components," explains Alessandro Franceschetti, Head of Structures for Luna Rossa.

"We are in a zone where we will be able to understand the behavior of these structures over extreme limits up to the very end," he adds.

The load cylinder can pull 35 tonnes. "There is no way back," says Franceschetti.

The test goes well with 180% of working load being called as the load cell reads over 27.3 tonnes before the foil arm explodes in a shower of carbon beyond the 27.5 tonne mark to the applause of the relieved engineers.

"We heard some cracking on the way up but we got to over 2.1 times the safe working load, and that was the expected minimum, says Franceschetti.

"We're good to go," he smiles. "We've got an arm, we look forward to seeing the AC75's on the water, now."

Second version of the video released May 23 by America's Cup Youtube channel

Uncut version - 7m30secs duration

For an earlier report on the destruction testing, including a description of the test cases and their purpose click here

Related Articles

ETNZ ranked #5 in major sport brands
Emirates Team NZ has been ranked at #5 on the global Sports Technology Power List In the 2024 Sports Technology Annual Review and Power List published Friday, Emirates Team New Zealand has been ranked at #5 on the global Sports Technology Power List by The STA Group who champions the best sports technology globally. Posted on 22 Nov
America's Cup: Ben Ainslie reflects
Ben Ainslie's thoughts subsequent to his riposte to the Kiwi sport commentator Topics covered include his most memorable moment of the Cup, his thoughts subsequent to his riposte to the Kiwi sport commentator and much more in this frank review of the Brits performance in the 2024 America's Cup. Posted on 20 Nov
Surprise move by America's Cup Event
Surprise announcement made to stop teams from sailing and testing The Defender and Challenger of Record for the next America's Cup have given notice of rules that will apply for the 38th America's Cup, effectively immediately designed to stop teams from sailing or testing, before the announcement of the next Protocol. Posted on 8 Nov
37th America's Cup through Jan Pehrson's lens
The AC75's have been a game changer not only for sailors, but for sailing photographers as well The AC75's have been a game changer not only for sailors, but for sailing photographers as well. The action is so quick, with boats speeds in the 40 knot range, that photographers and photo boat drivers must make lightning-like decisions. Posted on 26 Oct
Defenders want to expand on AC37 progress
AC40 and E-sports to be expanded. Barcelona not big enough for expanded teams Grant Dalton outlines the future of the 38th America's Cup - Womens, Youth and E-Sailing to stay. Barcelona lacks infrastructure for an expanded event. Visitor numbers and TV audiences are expected to reach targets. TV audiences will be 50% up on AC36. Posted on 22 Oct
Kiwis in awkward dance over Cup venue
Politicians of various hues have come out in support of New Zealand hosting the 38th America's Cup With the America's Cup still wet with victory champagne, the topic of New Zealand potential hosting the 38th Defence of the America's Cup arose during the weekly Prime Minister's Media Conference on Monday afternoon (NZT), in Wellington. Posted on 21 Oct
The challenge of INEOS Britannia
A brilliant campaign for the Louis Vuitton 37th America's Cup The most successful British Challenge in over 90 years ended in defeat after a spirited series against the Defender, Emirates Team New Zealand, that was closer and more hard-fought than the 7-2 scoreline suggests. Posted on 20 Oct
America's Cup: RYS confirmed as Challenger
Royal Yacht Squadron is confirmed as Challenger of Record for 38th Match The Royal Yacht Squadron has lodged a Notice of Challenge for the America's Cup, and the Cowes based club will be the Challenger of Record for the 38th Match. Sir Jim Ratcliffe has confirmed he will be back with the team, as has skipper Ben Ainslie. Posted on 19 Oct
NZ makes history with successful Cup defence
Emirates Team NZ concluded a historic chapter, winning the 37th America's Cup Match Emirates Team New Zealand concluded a historic chapter, winning the Louis Vuitton 37th America's Cup after an epic final showdown in Barcelona against the Challenger of Record, INEOS Britannia, in a single race that ebbed and flowed from the outset. Posted on 19 Oct
Cup Spy - Am Cup: Day 6 - Kiwis win Three-peat
Emirates Team NZ has successfully defended the America's Cup in a unique Three-peat Emirates Team New Zealand representing the Royal New Zealand Yacht Squadron has successfully defended the America's Cup in the 37th Match sailed off Barcelona. Updated: Omnibus video of Races 1-9 Posted on 19 Oct
Maritimo 2023 M600 FOOTER2024 fill-in (bottom)Vaikobi 2024 Black Friday