Deeper V hulls more likely to 'hook-up' & flip you out?

[Nos4r2]

I'll second what JK said.

You REALLY don't want the bow to suddenly drop at the wrong moment.

[landlord]

Agreed John K

I'm talking more about slowing down rather than chopping the throttle. Its about travelling as fast as its safe to do so in the prevailing conditions and experience of the helmsman. However JK your point is also correct.

[chris.moody]

Originally Posted by John Kennett

Bear in mind that there's nothing in any of the RYA Powerboat courses that really covers high speed boat handling, and some instructors may have some race experience, but many won't.

It's not always the case that slowing down is the best thing to do when things look scary. Chopping the throttle can be the worst possible thing to do, and can be a major factor in this type of accident as it can provoke a severe hook. The faster you go the more important it is to understand this.

For anyone with a fast RIB who reckons on travelling at 50mph plus, I would recommend spending some time with an instructor like Neil Holmes who really knows about driving a boat quickly.

http://www.powerboatcentre.com/

I regularly drive ribs and hard boats that can exceed 50mph and I'm always keen to increase my knowledge. Maybe two or three of us could share the cost of some training with Neil Holmes (or any other instructor that really knows his stuff about handling fast boats at their limits). I'll enquire about costs. Anyone else interested?

[brucehawsker]

Agree 100% with JK. Our 6.5M tops out at about 46-49 knots. Anything above 40 knots and the rules are to do everything slowly, unless you are executing a crash stop.

A hard turn - making sure crew are aware and holding on - at say 45 knots is fine on Farfetched unless you are trimmed out when she sort of skids which is a loss of control and hence scary. Trimmed in, while we have wondered if we are going over (but that is an illusion) the G forces do pile on.

In unpleasant Solent chop executing a hard turn can feel a bit unstable with some bouncing so we always throttle back to sub 30 knots.

Biggest danger for us is hitting wake from a big ship in dead calm at an angle when you sometimes just can't see it!!!! That is a good way to get teeth through lip syndrome.

At low or high speed, 99% of the time the rule is "do everything slowly". But I would suggest practicing the crash stop and of course MOB.

[brucehawsker]

Oh and yes I would be up for some high speed / rough going training if we could share cost!

[rocknrolla]

Originally Posted by John Kennett

Bear in mind that there's nothing in any of the RYA Powerboat courses that really covers high speed boat handling, and some instructors may have some race experience, but many won't.

It's not always the case that slowing down is the best thing to do when things look scary. Chopping the throttle can be the worst possible thing to do, and can be a major factor in this type of accident as it can provoke a severe hook. The faster you go the more important it is to understand this.

You are on the £ Looey its strange but right, when you have the rib at wot,forward momentum from the engine and the weight of the boat, fuel, crew. when its up and on it, its great but if you chop the throttle it will fall and stop like a brick,it feels like you have done some thing wrong, but the boat has just lost energy, so it takes it out on your spine or knees,is that close or what JK

[Jonny H]

It looks like this is caused by the boat hooking and it shows how violant it can be

Boat Crash at Lake of the Ozarks in Missouri - YouTube

[boristhebold]

Originally Posted by whisper

Basically it's caused by:

Going too fast.

Tight turns at speed if the keel comes out of the water and digs in again.

Chine walking can be another cause.

Going to fast for the conditions or hitting a wave or wake from another boat.

Showing off or not paying attention.

Alcohol !!!!

Put any of the above together with a kill cord that is not working or not worn could mean disaster....

I think whisper has it spot on with this simple list.

[Raygun]

So can anyone recommend a good book on fast power boat & rib handling covering the various do's and dont's so that a beginner like me can begin to understand better the various ways that a fast boat can get into trouble?

[9D280]

Back to the original Q - I assume on the PB2 you were shown how do do an emergency stop?

That's a controlled version of what is being discussed, and yes, I have nearly gone overboard on SR4s with as little as 25HP on the back on a couple of occasions whilst checking the handling of a particular rescue boat setup before a dinghy event.

It's not just a high speed thing.



http://www.rib.net/forum/f8/chine-wa...tml#post421932 (post #8)

[woody73]

Originally Posted by Raygun

So can anyone recommend a good book on fast power boat & rib handling covering the various do's and dont's so that a beginner like me can begin to understand better the various ways that a fast boat can get into trouble?

From what I make out, you seem to be a very sensible chap!
The only advice I can give you is to slowly get used to the handling characteristics of your boat bit by bit. By this I mean get used to it in flat calm conditions, then move onto slight, moderate and so on. And if it looks like its going to be too rough then save it for another day.
The majority of us on here are pleasure boaters so what is the point of doing tight high speed turns other than in an emergency. The thing I'm putting across is if we ease back a little on the throttles we give ourselves more reaction time to deal with and see rogue raves, wash from ships etc.
The only people that need to be taking risks such as tight turns and breakneck speeds are on the competitive circuit.
My advice is, you get more pleasure out of 'pleasure boating' by keeping speeds moderate,
It's also kinder on the wallet and you'll be able to walk the next day.
And finally please please keep the kids aft on anything other than flat calm!

[Cookee]

Originally Posted by Raygun

i'm concerned to know what causes a boat to flip violently and are deeper V hulls more susceptible than slightly shallower hulls? Is a deeper Vee more likely to dig in deep when coming down on a bend and thus more likely to stop the boat sharply flipping the occupants out?

In my opinion deeper Vee and Stepped hulls are more likely to hook but any boat hard or RIB will do it given the wrong circumstances.

Originally Posted by Raygun

Similarly, do deeper Vee hulls give a softer ride through the chop but end up being more likely to flip?

One of the ways that ribs can flip, i understand, is if when turning tightly at speed the weight of the boat rests on the inside tube effectively lifting the hull higher in the water giving it less grip and that feeling of slipping. If you then hit a bit of chop with the inside tube can it then bounce & flip the boat right over the opposite way violently launching the occupants out? Is a deeper Vee more susceptible to that?

Yes deeper Vee hulls do give a softer ride.

The inside tube lifting the hull is a bit of an extreme situation and if you're in that situation you would be somewhere around the limit of the handling of a boat anyway.

Originally Posted by whisper

Basically it's caused by:

Going too fast.

Tight turns at speed if the keel comes out of the water and digs in again.

Chine walking can be another cause.

Going to fast for the conditions or hitting a wave or wake from another boat.

Showing off or not paying attention.

Alcohol !!!!

Put any of the above together with a kill cord that is not working or not worn could mean disaster....

I would add "in a following sea" which would also increase the chances of broaching which is a slow speed hook, more common in displacement boats but still possible.

I wouldn't choose a hull based on deep or shallow Vee for safety but rather to suit your boating, I would then either treat the boat with a lot of respect, get it maintained properly and follow all safety advice, if it still goes wrong then you're very unlucky! If you want to go faster and push the limits in terms of speed or more challenging conditions then get some training