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Old 03 October 2013, 08:24   #1
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Riding on the back of a wave in a following sea

Has anyone ever noticed that when riding on the back of a wave in a following sea, that the power sometimes seems to get robbed from the engine and the engine will sometime appear to labour?

I assume that this is due to the circulr motion that a water particle has within a wave and this motion is trying to pull the boat down the back of athe wave.

TSM
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Old 03 October 2013, 08:42   #2
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Yes I have have noticed this too, first time it was quite alarming as I was in big seas over a bar, thought I had lost the prop or sumitt
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Old 03 October 2013, 08:57   #3
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It's just the fact your trying to drive the boat up a big hill.... usually water is flat!
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Old 03 October 2013, 09:11   #4
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Quote:
Originally Posted by two stroke mick View Post
Has anyone ever noticed that when riding on the back of a wave in a following sea, that the power sometimes seems to get robbed from the engine and the engine will sometime appear to labour?

I assume that this is due to the circulr motion that a water particle has within a wave and this motion is trying to pull the boat down the back of athe wave.

TSM
I remember one particular incident coming out of Milford Haven round St Annes head, we had a 6.4m Osprey at the time with a 175hp inboard. As we rounded the head we hit a patch of standing waves & got half way up the back of one & then started to slide backwards 4rse first into the trough & this was at WOT The boat was near vertical & I thought she was going over backwards, luckily we managed to crest the wave & escape, scary
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Old 03 October 2013, 09:40   #5
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Horsepower doesn't count for much when you're pointing into the sky, and as it's slow going in these conditions you're effectively trying to do a standing start up a very steep hill.

The "Isle of Man" trip a few years ago saw us in some interesting conditions off Anglesey, stern sliding a big Ribcraft with 250 screaming horsepower doing nothing at all. Poly seemed to take it in his stride, but the rest of my crew have never set foot in a boat again!
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Old 03 October 2013, 09:43   #6
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Not nice looking at the sky in a NASA launch position!!
This happened to me going to the Scillies with Whisper and company on the Runnel Stone just off Lands end.
Not much fun in a small Rib.
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Old 03 October 2013, 10:05   #7
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Not much fun in a small rib!! Awesome fun in a small rib
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Old 03 October 2013, 10:18   #8
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Not much fun in a small rib!! Awesome fun in a small rib
Not when you really really think you are going over! It stayed vertical for several seconds before dropping back down. The rubber seal on the engine cover actually got turned up at the back.
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Old 03 October 2013, 10:35   #9
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Not much fun in a small rib!! Awesome fun in a small rib
Yeah till YOU Stuff it!!! eh Matt!
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Old 03 October 2013, 10:37   #10
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Not much fun in a small rib!! Awesome fun in a small rib
Yeah but your nuts
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Old 03 October 2013, 10:45   #11
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I be with MattH on this one. I also think it is good fun but requires a lot of wok to keep the boat on the back of the wave
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Old 03 October 2013, 11:37   #12
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It's just the fact your trying to drive the boat up a big hill.... usually water is flat!
Yep, like uphill pedalling on a bike. The hull wants to slide back down the wave.
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Old 03 October 2013, 13:39   #13
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Yep, deceptively fast moving water.........
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Old 03 October 2013, 13:43   #14
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I've had a similar problem — following a wave in at about half throttle, off the plane so going too slowly to land, opened up to WOT and got no response at all.

The much finer prop that'd been on there previously was much better for climbing waves (but a bit too much of a compromise for everything else). The technique for approaching the beach has needed a bit of a re-think since then...

Also, water runs downhill — so rather than being exactly like driving uphill, it might be like walking up the wrong side of an escalator. (Third hand wisdom of my brother's old dinghy sailing coaches there — I'd be interested to see any figures on whether it's true and to what extent.)
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Old 03 October 2013, 13:57   #15
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Still just about the safest place to be in a big following sea
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Old 03 October 2013, 15:32   #16
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Quote:
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Horsepower doesn't count for much when you're pointing into the sky, and as it's slow going in these conditions you're effectively trying to do a standing start up a very steep hill. The "Isle of Man" trip a few years ago saw us in some interesting conditions off Anglesey, stern sliding a big Ribcraft with 250 screaming horsepower doing nothing at all. Poly seemed to take it in his stride, but the rest of my crew have never set foot in a boat again!
I remember that day well, we spent most of the day vertical on the way back to Conway it's a good job we ventured out the next day or I would of sold my rib to the 1st person who wanted it
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Old 03 October 2013, 15:34   #17
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the rest of my crew have never set foot in a boat again!
De waivs ad nuffink too doo wiv itt

Yorr croo jus didunt lyke yew
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Old 03 October 2013, 15:36   #18
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You should try it towing your mates broken down rib with his divers on yours complete with 8 cylinders.....
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Old 03 October 2013, 15:36   #19
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Yep, deceptively fast moving water.........
Agree for a breaking wave, when duck diving.
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Old 03 October 2013, 15:38   #20
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De waivs ad nuffink too doo wiv itt

Yorr croo jus didunt lyke yew
Haha .. he was determined to have retribution for years of spamming posters maybeez ye were selected
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