Tuesday 8 January 2013

Delivery to HK: updating the routing algorithm...

Position 10:00am 18 42N 112 59E
The four routing suggestions.  If you're interested in this, see the post
yesterday for explanation of the various lines... The two white dots are shoals:
the one to NE, smaller, is St Esprit Shoal, the other Helen Shoal.  Both 10m
but would want to be avoided for wave actions given current conditions...
To be fair to the routing suggestions of Predict Wind, which I criticised yesterday in the post immediately below, they were based on 100% of boat polars. I've now adjusted that to 75%, given that they're not racing, and that seems a lot closer to reality, with boat speeds predicted now closer to actuals. Though TWA's still seem to be too tight, not sure why that is, as I've set it to "Sail only", since the engine is currently not working in gear..... I've also adjusted boat speed to a thing called "Wave Polars", which let you change the boat speed to the size of waves, TWA and wind speed. That's all a bit of a guess...
Judy has asked about ETA, which I answer in the comments...  In sum, it's between 2.5 and 3.5 days.

5 comments:

  1. Great to get your updates Peter.

    Do you have an ETA for them back in HK?

    Bucket x

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  2. Hi Bucket,
    Current ETA is between 2 and half and 3 and half days, depending on which routing prediction you favour. The fastest route is based on the Canadian data (CMC) rather than the US Data (GFS). Whether that turns out to be true, we'll see. Grant has the data on board, but is just playing the shifts as they are.
    I'd be inclined to think it'll be the longer not the shorter, given currents, etc. Also, they're without engine working in gear (engine works, but doesn't drive the boat when in gear... oh, dear...)
    cheers
    forse

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  3. Tricky agorithm .. anyways get'n closer now .. "put another log on the fire" "cook me up some bacon and eggs." Don't think Grant'l be sprint'n to the Airport wet weather gear 'n all to catch his 15th Jan Flight to N.Z. I know all 3 will be feel'n ecstatic as H.K. ominously CLOSE. Thanx to the Sea Gods bringing "Xena" and the Boyz safely thus far .. and before too long beckoning to it's call all ova again .. "Home is the Sailor..Home from the Seas"

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  4. Yes, Iris, pretty chilly here (13 C) and even chillier on board..... They're just south-east of Limas; should be home and cosy this afternoon, I'll go down to meet the boyz...
    cheers,
    forse

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  5. 8.30p.m. here N.Z. (23DegC) I'm so excited "Xena" and the Boyz at R.H.K.Y.C. safe and sound .. such a Looooooooong Journey .. Well! it's Cheers!!!! to Grant, Noel, Oscar and the Seafaring Warrior Princess "Xena"
    and.... Humungus Thank You Peter for Predict Wind Tracking.
    Iris xx

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