Newbie - planing advice

Seahope

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All,

Is there a rule of thumb of what conditions are OK to power up? I'm currently assuming that wind of < 10 mph and sea state of calm is required, but am I being so conservative that I'll never see that in the Solent?

My boat has 2 x 240hp Yanmars and the hull is about 29'.

All advice appreciated.

I ask because a few weekends ago we left Portsmouth Harbour headed to the Isle of Weight straight into a strongish head wind and the ongoing waves and I couldn't 't seem to get her on the plane. Nose went up OK, engines sounded normal, lots of wash but it just didn't seem to want to plane and it was too bumpy to continue. The only difference from the last time time was the wind and the fuel tanks are now half empty.
 
Have you got a set of trim tabs...I'm assuming yes.

Get them so they push the nose down as you are putting on the power so you get over the hump...after that play with them to get the best position to speed ratio.

Unless you are carrying some concrete blocks, 2x240 HP's should get you moving.

Is the bottom of the boat clean? Any weed?

As speed for sea conditions....I'm no sure there are any hard and fast rules...Keep it safe and comfortable...Build up your speed slowly and if it starts to get a bit crazy, drop it down.
 
Last time only the two of us at the helm whereas before there have always been 3 or 4 people.

Yes, I do have trim tabs but the gauges for them don't work and there are two different sets of rocker switches for them and I need to work out which ones actually do something. Next time I visit the boat with sometime I will check to see which ones to use and how many seconds they take to go down/retract.
 
What leg trim are you using? Should be something like -3 to get up on the plane and then bring back towards 0 when over the hump.
 
Used to have a Monterey 250 with only 1 240hp Yanny in and 27ft long that used to plane about 17/18k but needed trim tabs to get her over the hump. You should be good for 33-35k+ I would have thought with 2 and 29ft. Make sure your legs and trimmed down until she is planning. Mine was on a Bravo II leg and that engine and leg combo is known for taking out prop bushes.... if you think you have a drive issue. but not sure what you have.

Mind you with two 240s sat astern, she probably (as has been said) does need trim tabs down to get her nose down. I would get these working first.
 
Is there a rule of thumb of what conditions are OK to power up? I'm currently assuming that wind of < 10 mph and sea state of calm is required, but am I being so conservative that I'll never see that in the Solent?

Not sure exactly which boat you have, but you should be able to get on the plane in almost any sensible conditions. e.g. An S28 is almost 29ft, and two 170hp engines are enough to cause it to leap onto the plane without much delay although you need plenty of throttle if it's bouncy, then back off to "min planing speed".
 
Used to have a Monterey 250 with only 1 240hp Yanny in and 27ft long that used to plane about 17/18k but needed trim tabs to get her over the hump. You should be good for 33-35k+ I would have thought with 2 and 29ft. Make sure your legs and trimmed down until she is planning. Mine was on a Bravo II leg and that engine and leg combo is known for taking out prop bushes.... if you think you have a drive issue. but not sure what you have.

Mind you with two 240s sat astern, she probably (as has been said) does need trim tabs down to get her nose down. I would get these working first.

We have only been out once ourselves in our Monterey and there were no problems planing the previous two times, but then we were being accompanied by very experienced skippers.
 
I'm not quite sure of your question, is it the conditions that are stopping you planing, because it's too bumpy, or can the boat not get on the plane? You have quite a lot of power for a 29' boat, it should plane easily, with or without the trim tabs down, so if it wont plane at all then I think you have a problem.

If you're asking about which conditions you should plane in, then only you know the answer, because it's what you're comfortable with. You'll always find it much bumpier heading into the wind/waves, and a much softer ride going with them.
 
I'm not quite sure of your question, is it the conditions that are stopping you planing, because it's too bumpy, or can the boat not get on the plane? You have quite a lot of power for a 29' boat, it should plane easily, with or without the trim tabs down, so if it wont plane at all then I think you have a problem.

If you're asking about which conditions you should plane in, then only you know the answer, because it's what you're comfortable with. You'll always find it much bumpier heading into the wind/waves, and a much softer ride going with them.

Nick, you are quite right. I am not sure of the answer either. I will only know if there is a problem next time we go out and try again. Last time I checked the engine revs and both were up around the 3800 mark and the nose did drop a little but the speed remained low < 15 knots. On previous trips the boat had entered the plane almost instantly i.e. full power, nose up, nose dropped, throttle back leg up a little for maximum speed of around 32 knots.
 
Nose went up OK, engines sounded normal, lots of wash but it just didn't seem to want to plane and it was too bumpy to continue.
With a couple of 240 engines (and diesel!) on a 29 footer, you should jump on the plane regardless of tabs - unless something's not working properly. Did you try a different heading, instead of straight against the waves?
Anyway, since you say it was too bumpy even without planing, it must have been some remarkable sea...
As a rule of thumb, I wouldn't fancy a cruise ar ANY planing speed against a headsea, when that's strong enough to be uncomfy also at slow speed.

PS: whoops, I didn't see N_H post and your reply 'cause I was writing mine...
 
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With a couple of 240 engines (and diesel!) on a 29 footer, you should jump on the plane regardless of tabs - unless something's not working properly. Did you try a different heading, instead of straight against the waves?
Anyway, since you say it was too bumpy even without planing, it must have been some remarkable sea...
As a rule of thumb, I wouldn't fancy a cruise ar ANY planing speed against a headsea, when that's strong enough to be uncomfy also at slow speed.

PS: whoops, I didn't see N_H post and your reply 'cause I was writing mine...

Dunno. I often find it much better to plane over rough stuff, not always of course.

But then, is there ever rough stuff in the Solent?? Particularly, if the waves are coming from IOW.
 
There can be a nasty chop that can spoil your day if wind/tide/depth are not playing ball. Not exactly big waves, but a short banging that causes teeth to fall out.

In many ways, bigger offshore waves easier in that the whole boat just goes up and down a bit.
 
Dunno. I often find it much better to plane over rough stuff, not always of course.
I guess you mean with some choppy sea (a couple of feet or so), which is in fact also the optimal condition to achieve max speed, counterintuitive as it might seem.
Surely not in any sea rough enough to make slow cruising "too bumpy to continue".
Now, whether that can be found in the Solent, that's a different kettle of fish of course. I didn't think of it 'cause I don't know those cruising grounds. Surely, looking at the map the fetch seems shorter than what I have on the lake...
 
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