I've been in daily contact with Grant and the Boyz, by the on-board email, as they wend their way to Hong Kong. Seas nasty on beam, winds up to 40+ knots, wet and cold [eg: Grant on 4th Jan: The GFS & CMC so far below actual not sure why they predict 18 & 19 we get 38 & 42 actual]. From Grant today:
Around 26Knts here all day and nasty cross sea....wet wet wet and cold Brrrrrrrrrrrr
Noel and Oscar wearing every bit of clothing they own ..then wet weather gear over ...........look like round balls with two eyes peering out...
Comment about the Predict Wind wind predictions and routing suggestions:
Wind speeds predicted by PW have consistently been below what experienced, they saying around 20-30, while experienced on board over 40 knots. Their suggestion for routing has higher boat speed than is achieved, or is reasonable, and they have the boat going to weather at tighter True Wind Angle (TWA) than is achievable: saying as close as 22 degrees TWA (!), when the best we can do in racing circumstances (let alone cruising) is 39 degrees TWA.
That's strange, given that the program has all our boat polars inputted. This exercise has me wondering about the usefulness in offshore racing....
Overall, and so far, I'd say the CMC routings are better than the GFS routings. And I think GFS/CMC better than PGW/PWC.... [that's subject to review at the end...]
Around 26Knts here all day and nasty cross sea....wet wet wet and cold Brrrrrrrrrrrr
Noel and Oscar wearing every bit of clothing they own ..then wet weather gear over ...........look like round balls with two eyes peering out...
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| Position at 11:00 today 18 05N 111 33E, making 7 Knots SOG, 086T |
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| This is the PredictWind suggested routings on "comfort" setting. The green pin is Xena's position. The blue dots towards HK are PWG, the red dots are PWC which are Predict Wind's overlay of their algorithms on GFS and CMC data respectively. The light blue line is GFS data and the light red line CMC data. |
Wind speeds predicted by PW have consistently been below what experienced, they saying around 20-30, while experienced on board over 40 knots. Their suggestion for routing has higher boat speed than is achieved, or is reasonable, and they have the boat going to weather at tighter True Wind Angle (TWA) than is achievable: saying as close as 22 degrees TWA (!), when the best we can do in racing circumstances (let alone cruising) is 39 degrees TWA.
That's strange, given that the program has all our boat polars inputted. This exercise has me wondering about the usefulness in offshore racing....
Overall, and so far, I'd say the CMC routings are better than the GFS routings. And I think GFS/CMC better than PGW/PWC.... [that's subject to review at the end...]
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