GPS v Log

[NigeCh]

Bollocks

If you take a paddle log underside or overside you will get a different reading .... and then you leave the boat for a few weeks and get a SINGLE baby barnacle on the wheel, then you'll get a different reading.

There's no scoring sofar on this thread ... It's all about why logs or patent logs have no place where GPS plus a bit of old fashioned 2B pencils on paper charts with tide atlass's rule the day.

The practicality of the log is part of the, IMO, well and trully past.

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[Mirelle]

Log accuracy

Like a few other old fossils, I still carry, and use, on proper passages, a Walker Excelsior IV trailing log. Unlike the paddle wheel log, the Walker is notably accurate, and if anything it "fails safe" because it will over read slightly in rough weather (due to the rotator being towed up and down seas rather than through them) so if you are running down on a danger it will tend to say you have arrived before you have done. This error is of the order of 2-3%, say three miles UK/Holland (in my case).

(If you still have the conversion table that they used to come with, you can calculate speed by timing the flywheel rotations with a stopwatch).

I have never been able to get a paddle wheel log to behave anything like as accurately, although the paddle wheel log is a very useful thing for showing speed variation and for recording short distances, eg in fog.


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[charles_reed]

Re: Log accuracy

I still have the Walker log, albeit with one of the brass trailing logs missing - it got ate by a "fish" whilst coming down the Bristol channel.
I have to agree, it's infinitely more accurate than the paddle-wheel thing, which is only there to amuse visitors on board.

Both are virtually redundant thanks to GPS.


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