America's Cup - Glenn Ashby on why Emirates Team NZ went cycling
by Richard Gladwell, Sail-World.com on 20 Feb 2017
Emirates Team New Zealand's new AC50 sailing for the second time from the Team's base in Auckland. February 15, 2017 Richard Gladwell
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There are few secrets around the Auckland waterfront.
In a nation where anything America's Cup is usually top of the primetime TV news the story headlines often open with: 'One of the worst kept secrets in sailing was confirmed today when.....'
But not last week.
After the revelation that Emirates Team New Zealand had switched from grinders to cyclists, how did the potentially game-breaking development remain a secret for so long?
'The team started work on the project three years ago, but the actual testing started 18-24 months ago,' explained skipper, wingsail trimmer and Sailing Director, Glenn Ashby.
The Australian sailmaker is one of the top multihull sailors in the world, with 15 world championships and an Olympic Silver medal to his credit. This will be his third America's Cup.
'The team has done well to keep it under wraps for all this time. There have been a lot of different industries involved to help us. It has been great to have been able to keep it in the bag for as long as we did.'
'It was something we had talked about as a group a long time ago. Most of the teams have looked at it; I'm sure over the years. We were open minded to it from Day 1 and being only a small group we agreed it was an option and ran with it from there.'
'It involved resource and effort from every department within the team, along with a lot of other areas. It emerged as an option after some initial testing. With more development and learning it just kept on stepping up the priority list to look at more closely.'
'Once we decided to take it on, we just went 'full noise.'
Many believe Emirates Team New Zealand made a mistake in the 34th America's Cup flashing their foiling ability in the AC72 too soon - and allowed their competitors to play catch-up, eventually beating the Kiwis at their own game.
So secrecy was vital, particularly with the other America's Cup teams owning multiple AC45S test platforms and being able to test the merits of grinders against cyclists in two boat testing if they wished.
For Cup aficionados, the sight of four cyclists pedaling at peloton pace in place of hunky grinders on the pump handles signaled the end of an era that began 60 years ago, when 12 Metres were first used in the America's Cup.
The exception was the Swedish 12 Metre Sverige, which contested the 1977 Challenger Selection Series, going down to Alan Bond's Australia in the Final. The Swedish entry had several novel features including tiller steering - as well as cyclists below decks powering the winches.
Forty years later the cyclists have emerged again - except this time they are providing manual power onto a hydraulic fluid reservoir. In another extension of sailing technology, the New Zealand AC50 does not have any winches or sheets for that matter.
All sails are controlled or sheeted by hydraulic controls.
Crew weight limit spells end for big grinding units
With an average crew weight limit of 87.5kg imposed for the AC50, the luxury of being able to carry hulking grinders generate the bulk of the power is past. A lighter weight grinding solution with the power of the old, is required.
'It is a massive one to take on,' Ashby concedes. 'Pedal-power has been tried in the past, but teams have discounted it for various reasons. With the technology and materials that are now available, and with a lot of clever guys all working on one project for quite a while anything is possible now.
'It's up to the sailing team now as to how to get from one side to the other and learn to sail the boat. They have a big challenge coming up over the next few weeks.'
'We wouldn't have done it if we didn't think it had advantages over existing grinding systems.
'One of the advantages we saw along the way was for the guys to be able to use their hands in different functionalities on the boat instead of just on grinding pedestals. While they are putting in power, they can be doing other functions more accurately, than they can do with their feet on existing grinding pedestals using floor buttons.'
'Obviously, using greater power out of your legs, as opposed to your upper body, has always been on the table. Hopefully, the jig testing, the pump development and the system development that we have done will pay dividends and give us a bigger range of gears in the gearbox than what could have done potentially with grinders.'
'Efficiency is one of the keys to getting the boats around the track. But the boats are very under powered as far as what you need to do all the maneuvers, adjusting the wing and the foils - more than once in some maneuvers. I don't think there would be any team out there who says 'we have got too much power.'
'The challenge is to use as much power as you can as effectively as possible. If you have extra power and can use it efficiently then hopefully that turn to speed against your opponents - and that has been our focus.'
What about the Wattage?
Although Emirates Team NZ have never released any comparative numbers, the power of a top Olympic cyclist is about 500watts (about .75HP), the power of a top grinder is in the 250-300 watts range, and the power of a rower is around 480 watts.
It follows that during a tack or gybe two of the cycling grinders can sprint-mode to substantially increase the power to maintain the near-full team output, while the other two are crossing the boat. The process is repeated as the second pair of cyclists comes across, and when the peloton has reassembled, they can resume the normal sailing pace - probably of around 300watts each - the same high-end power as a top conventional grinder.
Being generous, the high-end power for the conventional four-crew grinding team is around 1000-1200watts. The high-end combined power of the cycling grinders is probably around 1900watts - or over 160% of the conventional grinding team - giving a significant edge in total power and meaning that the cyclists can more than equal the power of the other AC50 grinding teams. The substantially reduced work rate allows the cyclists to back off and get some recovery time while still staying warmed up.
The cycle option also gives the flexibility of allowing one or two cyclists to be more focused on sailing the boat - effectively doubling the available sailing crew - while not necessarily reducing the level of energy being applied to the boat.
In the America's Cup, two crew members are allowed to be rotated off between races - allowing a fresh set of arms to come aboard. That can also happen with the cyclists and will depend on how the concept unfolds.
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Go-Live from Day 1 on the pedals
Ashby says the Kiwi team didn't test the cycling power on their AC45S test platform, which was launched last June.
All testing for the viability of cycle-power was done on-shore, using cockpit mockups and wind tunnel testing.
'We did a lot of work with Cycling New Zealand early making sure the ergonomics were right. It is a very complex issue. I can see why other teams have dismissed it because it is complicated.'
'We designed, engineered and built the system in-house, but we did get a huge number of parts done externally. We did utilise a lot of our suppliers and wonderful sponsors to help us put those pieces together as a whole,' Ashby says.
'The first day of sailing (Tuesday) was always going to be a bit of an eye opener. We were foil taking and foil gybing on Day 1 after a structurally commissioning everything. That was quite an amazing feeling to be able to pull those maneuvers off. The first boat to ever to a foiling tack in the world with the guys on pedals!'
The sages of the America's Cup world have been quick to note that there are considerable G-Forces on crews of the various AC multihulls and that the Kiwi cyclists may have significant issues in keeping their balance during maneuvers - particularly at the top end of the wind range.
'There are some braces and bars the guys hang onto, ' is Ashby's response.
'But it is definitely an issue. The G-forces are high. It is something we have worked on a lot. We have done a lot of testing and development on various ways the guys can brace themselves.
'We also did a lot of work on the ergonomics and positioning of the guys on the boat. The cockpits are tight. There is not a lot of room, and they are big guys who are overlapping at times. We figured that it was worth it. Aerodynamically there is a component to it, and we have done a lot of wind tunnel testing. '
'In terms of aerodynamic drag, standing up and grinding is definitely bad. Even kneeling is not super flash and when you look at the data in the wind tunnel, neither of them are that great.'
Individual gearing?
Ashby won't be drawn on the whether the new system is set up so that each grinder can work individually, or if the pedals all drive a single centralised drive to the hydraulic reservoir pump. With conventional grinding systems, there are usually two physically matched grinders on the two pedestals, with body position and grinding technique being vital.
The cycling option means that all grinders can work within their comfortable individual heart rates, rather than being constrained by the capabilities of your other half on a grinding pedestal.
Grinding effectiveness and output is also affected by various ergonomic issues associated with traditional pedestals - correct body position - and that one grinder is always grinding forwards, while the other is grinding backward.
Cycling is much more simple - you just pedal in an upright position, hanging onto a bar across the boat which can also contain sailing controls - either on the bar or at the side. These can be easily and accurately adjusted the way a road cyclist adjusts the gears.
'When everything was weighed up we got the green light to go ahead with the pedals, instead of using conventional systems.'
'Some things might be easier with grinders; some might be easier with the way we are doing it. We will have to learn and evaluate it over the next few weeks and make the right call. At this stage of the game, from the little look we have had at it, it feels fantastic.'
'We will have to learn to sail the boat well. No-one has done what we have done before in a racing 50ft catamaran - let alone with pedals under your feet', he adds.
'On Tuesday, after our fourth tack, we managed to pull off a nice foiling one. That was after commissioning the boat for about an hour and a half it was pretty amazing to push the boat hard and pull off a couple of really nice tacks one after the other, plus a few nice gybes. But having said that we are out to learn and are only just scraping the surface.
'We just have to keep learning and pushing hard. All the other teams are going to be extremely competitive - and we have a huge hill to climb before we even get to Bermuda.'
Impressive first sailing sessions
Although Emirates Team New Zealand is the third team to unveil their AC50, they are the first to sail.' (The British were the second, sailing in the weekend in Bermuda.)
In the first two sailing sessions, the 30year old team looked to have continued where they left off with the AC45S, which was decommissioned in December.
A noticeable feature is the extreme bow-down trim and the ability to sail with the bows just a handsbreadth above the water.
'If we can keep the windward hull not too far away from the water we feel it is nice,' Ashby explains. 'In different moding, we sail the boat with different heels. The boats sail very nicely with a bit of bow down trim. We are also trying to get the windward rudder out of the water to reduce drag, and reduce wetted surface which seems to help.'
'You don't want to be dropping either hull in the water if you can help it. It is a very fine line to be able to get the absolute maximum performance numbers out of the boat. The more accurately you can sail the boat, the faster you can go - the same as any boat, ' he adds.
The other half of the switch to pedal power is physically conditioning the crew.
A vital part of that process was the hiring of 2012 Bronze medal winning cyclist, Simon van Velthooven.
'We have had Simon with us for 12 months,' Ashby explains. 'He has come in as a pro cyclist and a sprinter. He sets the bar for our sailing team guys to be able to get to his level power-wise. Our guys have stepped it up massively. Simon has done a lot of the testing with us and has been a great help, but I think he has got his work cut out for him as he has some guys gunning for him in the power stakes. They are all pushing some big numbers.
'The guys coming off dinghy sailing have all done a lot of cycling in the past. Our trainer has been able to transition the guys from a grinding based environment into a cycling based environment. They have all stepped up as a group and really pushed each other hard - and then used Simon to set the bar at an Olympic level.
'We have a huge amount to learn as to how to sail the boat, but in the power stakes those guys have done a great job and will continue to get better as we go forwards.
'Almost a year and a half ago we started phasing this in as part of our training program. As we neared launch date, we tapered the training more and more into developing power the lower half of the body. It certainly isn't something that has been left to chance or the last minute.'
'The physical conditioning is not a switch you can do over a couple of months - the conditioning has to be done over a long time, and hopefully, we have done enough to be strong enough to make it work properly.'
Extreme drag reduction
The very clean deck layout on the AC50 underscores the attention given to parasitic drag reduction - one of the few areas of open design on the otherwise one-design boat.
That approach stems from the ability to run every control system via hydraulics - which is turn is facilitated by the additional energy/pressure generated by the pedaling crew.
'On the 72 we had a winch on the wingsail and had six guys attached to it trimming hard to move the wing and sail the boat accurately,' Ashley recalls. 'Effectively nothing has really changed here - the accuracy in the aero trimming has a huge impact on how the boat actually sails - you certainly use plenty of power on these boats. The more you have, the more you use.
'The accuracy in the aero trimming definitely has a big impact on the how the boat sails. You definitely use plenty of power on these boats and the more you have, the more you use. Hopefully, the better accuracy results in a better performance, and for accuracy you need power.'
On their test platform, the AC45S which was effectively stretched to become an AC50 - and sailed with an AC50 wingsail, daggerboards, rudders amd was the same sailing geometry as the race boat.
The Emirates Team New Zealand AC45S used the same grinding pedestals as the other teams are using on their AC50's. It too was winch-less.
'We don't have a wing winch on this boat,' says Ashby. 'We have been hydraulic from Day 1 on the AC45S. That was because we were hopefully moving into this pedaling format.'
'As a wing trimmer I had to get used to trimming the wing in a different way - it was a massive learning curve for everyone. But I am glad we took it on when we did because it is quite a transition to go to a different system, and you have to teach yourself a lot of new skills.'
'It is a really different way of hanging onto a rope so to speak.'
'Now it is all hydraulics - a lot of buttons and a lot of levers. If I ever have to hang up my sailing boots, I will make a pretty good excavator driver! Might be Ashby Earthmoving in a couple of years - maybe!'
'Right now, I couldn't be happier as the Sailing Team Director, and as the wing trimmer on the boat, she feels fantastic. I am very pleased for the whole team that we have been able to get the boat on the water after such a massive effort, and for it to go out and sail as well as it has so far.'
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