Gladwell's Line: Boat Test on Chase Zero - the AC37 game changer?
by Richard Gladwell 14 May 2022 01:59 NZST
14 May 2022
Excellent visibility - Chase Zero - Emirates Team New Zealand - May © Richard Gladwell / Sail-World.com
After a few weeks of testing in Auckland, there is a little doubt that Chase Zero is a game-changer for the America's Cup.
We had our first look at the foiling chaseboat, during a mid-week media day on the Waitemata. Afterwards there was a quick first look at Emirates Team New Zealand's land yacht to be used in Project Speed - more of that later.
The sight of foiling AC75's being pursued around the America's Cup race course by a fleet of 14 metre chase boats pushed by an impressive-looking 1600hp bank of outboards will soon be a dim memory.
So too will be the roar of outboards with the throttles wide open - replaced with a low-pitched whine. We're told it is a combination of transmission bearing and foil noise.
With six aboard, and travelling at 30-40kts, the onboard verbal interactions are not a lot different from standing around the office watercooler having a chat.
All six people can talk normally. There is no shouted conversation into the ear of the person next to you. It's an ideal environment for VIP's, sponsors and media who can have the AC75 workings explained to them, as part of a normal conversation.
Chase Zero is a Pi foiled 10metre hydrogen-powered chase boat capable of hitting 50kts. The foiling chaseboat, has become a familiar but inaudible sight around the Waitemata Harbour over the past few weeks.
Chase Zero looks like a three-legged insect racing across the water surface, but the onboard impression is completely different.
Superb visibility is offered by a combination of the metre high ride height, the wrap-around windows, and the lack of water spray.
The ride is typical of a foiler - like ascending a metre or so in a lift, and without any banking or G-force - even in a high speed turn at 30kts.
There's no need for a death grip on a nearby handrail to avoid being thrown across the boat. If you want to be seated - plonk yourself in a basic foam padded seat, and put on a seatbelt, if you must.
The hydraulic seats essential for those back and leg-jarring rides in a regular chaseboats don't feature on Chase Zero either.
A look astern reveals a great sight - no wake!
Normal ride height for Chase Zero is 900mm to 1200mm above the surface. There's a screen in front of the helmsman showing a feed from a video camera aimed at the foils, in case some debris gets picked up.
"In rough stuff we might drop the ride height lower." says skipper Curly Salthouse. "We had a really good run the other day with three onboard and did five and a half of running around at 28-30 kts, with no issues in a variety of conditions including a cross breeze and a cross swell."
"It's a very comfortable ride," he adds.
Mechatronics Engineer, Michael Rasmussen explains that takeoff is done with the assistance of batteries - which acts as a buffer between the fuel cell, and provide additional instant power when required.
"The two fuel cells each produce 80kw. To get foiling more power is needed and there is some drawn down from the batteries to get lift-off. "
"Once it is foiling and at speeds up to 35kts, hydrogen power only is used, and the batteries are recharged. Above 35kts some extra power is required and that is drawn down again from the batteries."
"Cruise speed is 30kts, which is all done on hydrogen only with a range at that speed of 150nm, and we'd have about 10% of the fuel left.
"A fully tanked chase boat would theoretically require 850litres of fuel (given that the tank capacity is 800litres), compared to 30kg of hydrogen for the same trip," explains ETNZ's chase boat skipper Curly Salthouse.
"That was better than we hoped for," he adds.
Target time for a full tank refill is 15 minutes. The hydrogen power trainhas been fully automated and is very reliable. This means that the skipper can get on the boat, turn the start key and leave the dock without any assistance from engineers
During AC75 testing, the engineers and designers, while foiling at in Chase Zero at 30kts or more, should be able to follow the data emanating from the AC75 on their laptops and just look out the window to see what is happening on the water.
There is very little vibration on the boat and the ride sensation is similar to sitting on a bus. Working on a laptop or operating cameras at those speeds is easy on Chase Zero and near impossible on a conventional chase boat at those speeds in any sort of a seaway.
For several editions of the America's Cup there has been the dream of putting sponsors and VIP's aboard the race boats - offering a very unique experience, that is unmatched by other sports and events.
The on-board guest spot was a feature on the 83ft IACC keelboats used until 2007. But after the Artemis Racing tragedy in May 2013 the practice ceased.
In Bermuda several VIP boats were used for the 2017 America's Cup. They were a formidable force roaring around the race course, with VIP's trying to do the impossible of staying out of the spray, while being able to see what was happening. Many gave up.
Chase Zero with its enclosed cabin, excellent views and aircraft cabin ambience, offers VIPs, sponsors and their guests an unforgettable opportunity to see AC75 racing up close. And all while being able to converse at a normal voice level. It would be a magical experience.
There is plenty of space on the foiling chase boat for sponsor and teams signage and logo's - making them a distinctive addition to the Cup race flotilla and also serving as a foiling billboard.
In the ideal world, a version of Chase Zero could be developed to be used for photography and TV boats - allowing both shooters to get close to the action while only making the same amount of wake as a rowing dinghy.
The foiling Chase Zero option offers a better working platform than a regular photo boat - be it a Protector RIB or a Camera Cat.
In the 2021 America's Cup, two high speed camera cats were used, but were restricted to covering only half of the course each, because of speed and positioning issues.
The 90-degree high speed turns necessary to stay in contact with the AC75's generate huge G-forces on camera operators and photographers operating off the open air deck areas of the camera cats. That is despite being harnessed, with a short strop to very solid attachment points and body bracing against a central railing, while using both hands to try and steady and operate a camera.
The 10metre (33ft) HSV's resolve all those issues. They have negligible G-force, almost no discernable wake, plenty of speed (up to 50kts) Chase Zero can stay with AC75's - either astern or abeam and provide a better camera platform - and much-improved viewer experience, along with a much improved on the water commentary position.
There's one immediate issue with the Hydrogen Support Vessel (HSV) as the genre are known in the Protocol - there aren't enough of them.
At a cost of around NZ$2million or €1.2milion they are not cheap. But are also using technology which is fast developing and in strong demand. In future with some more innovations and better supply of components, the cost will reduce.
Whether there is a resale market for the 10metre foiler remains to be seen. One suspects that for the uber-rich, they will become the ultimate day boat, and something that is easily hoisted aboard a superyacht.
If the Protocol is not amended the teams will be required to have two each, which makes for a total of ten to be built. They can either order these from a builder authorised by Emirates Team New Zealand and using the tooling developed by the team in the construction of Chase Zero.
Or, they can build two themselves - provided they comply with the minimum prescriptions in the Protocol, which are the same as Chase Zero.
While the HSV's will always have their critics, the point is that they put a green face on what should be a green sport. The sound of a bank of four 400HP outboards roaring as tender chases after a silent AC75 travelling at two or three times windspeed should be a thing of the past.
Project Speed's land yacht was in several pieces. There is no doubt that when it goes on full display next Monday that it will be a very impressive piece of kit.
An interesting feature of the fuselage is that its length can be altered to optimise balance. Similarly on the outrigger weights can be added to optimise righting moment for the windstrength.
The pilot's cockpit looks very similar to that of a glider, seating just a single pilot, who will be using both hands and feet to guide the craft down an 8km salt bed, searching to register a new world record speed for just a three second period.
The wingsail is lying on its side having the finishing touches applied to its surface. It is a two element hard wing - quite unlike that seen on the AC72 or AC50. It is constructed in two solid elements. It presents a very slim leading edge, and is clearly designed and built for minimal parasitic drag. The vertical join between the two elements is almost indiscernable.
The land yacht is clearly designed around travelling in a single direction on a narrow range of wind angles.
Project Speed will be officially revealed on Monday when it will be rigged inside the Emirates Team NZ base. No photography was allowed before that event.
Both projects have enabled the team to keep their people employed and ready to go for the race boat build and AC40 fit-outs. The other team benefit is that both projects have required some out of the box design thinking, which keeps the team sharp, under pressure to deliver, and on a steep learning curve.
For sponsors, and particularly Toyota, the hydrogen boat project offers an excellent demonstration of technology in a way that would not be otherwise be possible.