America's Cup - Kiwis sign Olympic Cyclist for the Tour de Bermuda
by Richard Gladwell, Sail-World.com NZ on 15 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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Emirates Team New Zealand put in a second foiling display on Auckland's Waitemata harbour ahead of the official launching of their AC50 tomorrow.
With brighter skies, the cycling team took their places on the pedalstals and used leg power to provide the hydraulic pressure necessary to run the AC50's control systems for the foils and wingsail.
The story broke this afternoon that top New Zealand cyclist Simon van Velthooven (28), a 2012 Olympic Bronze cycling medallist had been signed by the New Zealand America's Cup team.
Yesterday's impromptu unveiling of the row of four bike seats instead of where the other teams have standard grinding pedestals triggered questions as to where the advantage really lay.
In US Sailing media Oracle Team USA quoted one of their grinders as being able to produce 300watts continually over a 25-minute race (746 watts equals 1hp). In the 2010 America's Cup where a small engine was used to replace a grinding team on Oracle's 120ft trimaran. The change was rationalised on the basis of quoted output of 250watts per grinder - with the eight grinders aboard being capable of producing a combined total 2.5hp or the power of a small sewing machine for a period of 40 seconds until lactic acid cut in.
A 2003 study of Emirates Team NZ grinders concluded that the grinding technique and correct body position was vital to achieve maximum effective output. The best effort produced around 550watts for 5 seconds.
Top cyclist Fabian Cancellara (SUI) is reported to have produced over 435watts over a 15 minute period having spent 55 minutes riding at Olympic Gold medal pace. He amped his output to 540 watts for two laps of the 70-minute race.
Double Gold medal winning rower Eric Murray set the world record 5km ergo (rowing machine) time taking 14 min 56sec with an average output of 480 watts.
The statistics would tend to indicate that conventional grinding platforms are the least efficient in producing power over a sustained period. The ultimate test being whether there is a drop in output from the cyclists in an AC50 multihull below that achieved by conventional grinders on the water.
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