What makes a 'Sea' boat?

Spannaz

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Strange question i know, but i'm new so please go easy.

I am curious to know what makes a boat a 'Sea' boat?

I see there are cruisers, then there are cabin cruisers and the list goes on. So is there specific type of design or hull that is better, or is it size, or is it the design?
I would assume taking a river cruiser and using it at sea is out of the question, being that the type really answers it.

But, say i wanted a boat for fishing, but somewhere comfy for the wife and kids,(toilet, running water, small sink/kitchen area) these seem common place on say cruisers, but a fishing boat...........well...............they are a bit sparse when it comes to creature comfort.

take the following advert for example : http://www.ebay.co.uk/itm/4-Birth-F...0104428?pt=UK_Power_Boats&hash=item4abd18e1ec

ideal but would or could it be used say around the coastal areas of the english channel? Not planning on a med trip, but something for day use etc.

thanks for your help

Stuart
 
More depends on weather and distance, a small planning boat is not suitable to put to see in any kind of wind, but on a calm day you would be amazed at the number of small craft out and about. Being sensible in a planning motor boat is about a good forecast, flat see for the duration of the forecast and very reliable engine with a back up and some means to carry out small repairs and safety equipment (radio and lifejacket at minimum flares I feel I need to add) oh and enough fuel and perhaps even two supplies.

You could find out about doing RYA power boat levels and getting a ride on different peoples boats and definitely a test ride on a potential purchase perhaps two one in calm and one in what the current owner would class as the limit.

Good luck and keep asking questions.
 
More depends on weather and distance, a small planning boat is not suitable to put to see in any kind of wind, but on a calm day you would be amazed at the number of small craft out and about. Being sensible in a planning motor boat is about a good forecast, flat see for the duration of the forecast and very reliable engine with a back up and some means to carry out small repairs and safety equipment (radio and lifejacket at minimum flares I feel I need to add) oh and enough fuel and perhaps even two supplies.

You could find out about doing RYA power boat levels and getting a ride on different peoples boats and definitely a test ride on a potential purchase perhaps two one in calm and one in what the current owner would class as the limit.

Good luck and keep asking questions.

thank you, often is the worry i am asking silly questions, however, the sea has no mercy and i have the utmost respect for it, hence i'd rather be slammed for asking silly questions, rather than get into trouble out there!
 
thank you, often is the worry i am asking silly questions, however, the sea has no mercy and i have the utmost respect for it, hence i'd rather be slammed for asking silly questions, rather than get into trouble out there!

The question you are asking is a biggie, and not at all silly.

Shape, strength, engine type, number, boat size. No one has come up with the answer, all boats do not look the same :D:D

I guess you have an area in mind? Go there ask some questions, what do local people use? Why?

All boats are a compromise, in one way or another, different areas have different priorities.

I have to agree seaworthiness should be high on the agenda.
 
There is no one line answer that will give you a 'sea' boat as opposed to a 'river' boat or a 'lake' boat....... There are just too many variables to look at, as others have said. Indeed, the same boat could be great for a river/canals with one engine but with a bigger engine be great for use at sea.

I would look round the other boats in use in the area where you are thinking of using it and seeing what other folks are using. Talk to people about how well/badly their boats work in the local waters; go and look round the local boat yards and brokers and talk to them about boats they's recommend. Between the 2 sources you should be able to form a picture of what would be OK to use locally.

Finally, if you were to do a the basic RYA powerboat course, then the instructor will be only too happy to talk your leg off about what boat to buy for your needs.

Hope that helps.
 
A lot of it is about equipment, as well. You can happily use a boat on a river with a much lower powered engine (inland waterways usually have low speed limits), and few navigational devices. So, a boat that is structurally fine for sea use might well be ill-equipped for it if it has always been used inland.

A sea boat needs:

  1. To be seaworthy; that is, strong enough to stand up to the sea, stable enough to be safe in waves, and comfortable enough for the crew in rough water.
  2. Be prepared for spending extended periods at sea; the weather can change while you are out, and it may be safer to stay at sea than to try and enter a harbour. A day sail can turn into staying out overnight quite easily.
  3. Be equipped for navigation under all circumstances. That will certainly include some training; knowing where you are is not just about equipment but also about knowing how (and when) to use the equipment.
  4. Ideally have more than one means of propulsion. Engines can fail; rigs can break.
  5. The primary means of propulsion should have power in reserve beyond that required to move the boat at "hull speed" in calm water. You may need it to get back to harbour against the wind or waves, for example.

Boats come with two basic types of hull: Displacement and planing. Displacement hulls are more comfortable in a wider range of sea-states, but are also slower; they are restricted to "hull speed" - that is (in knots) APPROXIMATELY 1.3 x the square root of the waterline length in feet. Displacement hulls also have more useable space below decks, though other considerations may make this moot. Traditional fishing boats and nearly all sailing boats are displacement designs.

Planing hulls are designed to skim over the top of the sea, and can be much faster. The majority of modern motor boats are designed this way. because they are designed to skim over the water, they are less effective if the sea gets up beyond a certain point which varies from design to design. The majority are also very uncomfortable in a rough sea, though this is not a certainty. Very few sailing boats with accommodation have this style of hull.
 
As well as fundamental things like hull shape and spare engine etc, I'd say a sea boat is one whose owner has spent time imagining the worst and equipping her for it, not just things bought off chandlery shelves but strong windows & hatches with emergency covers ready to fit, a brightly coloured cabin top or cockpit sole for other traffic and rescuers to spot, decent bilge pumps etc, in other words make the effort to take precautions.

Plan for the worst, hope for the best !
 
I would personally go for more fishing boat than flat speed or Timothy Spall barge :eek: Something similar to a small Colvic and you can have family comforts, an able sea going boat and have a play with some sails!
 
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We have a Colvic 22, the reason we got her is the same as your question in the opening post. We wanted 2 bunks for overnighting, a sink, room for a small cooker and a loo. It is without doubt the most solid, stable and secure feeling boat we have owned. The trade off....if there is one?....is its speed. A mind blowing, breath taking 7 knotts downhill !!
That said, we did do about 60 nm on a little over 25 lts of red last summer so it does have its benefits!
We had, prior to this, a 16ft fast planing fishing boat which got us to our marks very quickly, but after one season of chugging about we probably wouldnt revert back now......we just love the actual cruise out to the marks, kettle on, bacon sarnies wafting nicely, just enjoying being afloat.
It suites us perfectly, but as with everything, each to thier own.......
 
There is no clear dividing line between a sea boat and a non sea boat. It's simply that the further you go from land and the more exposed an area you are in, the more robust a boat needs to be.

Personally I would not go out to sea in a boat such as the one you link. Firstly it is small and size does matter. The capsize resistance of a boat (all other things being equal) goes up with the cube of the length.

I would not go out to sea in that boat because it only has one engine and that is an outboard. I've seen more disabled outboard powered small fishing boats towed into harbour than anything else.

But by "out to sea" I mean 10 miles off an exposed coastline. You would likely be OK pottering about the Solent in it.
 
The RCD categories help, but few small MOBOS get higher than Cat C for estuary or coastal type use. However, most of the boats you are likely to be looking at were built before the Directive came in so will not have a category. The one in your link was designed for inland waterways at displacement speeds with a small engine, but the hull form would probably allow planing with more HP. The plate will tell you max HP. However, it would not be a very comfortable boat in anything other than flat water.
 
We have a Colvic 22, the reason we got her is the same as your question in the opening post. We wanted 2 bunks for overnighting, a sink, room for a small cooker and a loo. It is without doubt the most solid, stable and secure feeling boat we have owned. The trade off....if there is one?....is its speed. A mind blowing, breath taking 7 knotts downhill !!
That said, we did do about 60 nm on a little over 25 lts of red last summer so it does have its benefits!
We had, prior to this, a 16ft fast planing fishing boat which got us to our marks very quickly, but after one season of chugging about we probably wouldnt revert back now......we just love the actual cruise out to the marks, kettle on, bacon sarnies wafting nicely, just enjoying being afloat.
It suites us perfectly, but as with everything, each to thier own.......

A happy man!!!
 
Strange question i know, but i'm new so please go easy.

I am curious to know what makes a boat a 'Sea' boat?

I see there are cruisers, then there are cabin cruisers and the list goes on. So is there specific type of design or hull that is better, or is it size, or is it the design?
I would assume taking a river cruiser and using it at sea is out of the question, being that the type really answers it.

But, say i wanted a boat for fishing, but somewhere comfy for the wife and kids,(toilet, running water, small sink/kitchen area) these seem common place on say cruisers, but a fishing boat...........well...............they are a bit sparse when it comes to creature comfort.

take the following advert for example : http://www.ebay.co.uk/itm/4-Birth-F...0104428?pt=UK_Power_Boats&hash=item4abd18e1ec

ideal but would or could it be used say around the coastal areas of the english channel? Not planning on a med trip, but something for day use etc.

thanks for your help

Stuart

owt that floats at sea.....lol
 
We have a Colvic 22, the reason we got her is the same as your question in the opening post. We wanted 2 bunks for overnighting, a sink, room for a small cooker and a loo. It is without doubt the most solid, stable and secure feeling boat we have owned. The trade off....if there is one?....is its speed. A mind blowing, breath taking 7 knotts downhill !!
That said, we did do about 60 nm on a little over 25 lts of red last summer so it does have its benefits!
We had, prior to this, a 16ft fast planing fishing boat which got us to our marks very quickly, but after one season of chugging about we probably wouldnt revert back now......we just love the actual cruise out to the marks, kettle on, bacon sarnies wafting nicely, just enjoying being afloat.
It suites us perfectly, but as with everything, each to thier own.......

ahh now that does sound perfect. I am in no means planning a trip 10 miles offshore, certainly not in the near future at the very least. The thought of that terrifies me to death.
Funny you mention the Colvic as i saw a similar one on ebay and liked the layout.
I don't plan on using the boat in the link, it was just an example of 'could' something like that be used in coastal waters, obviously any boat needs 2 means of power, having only one is a risk not worth taking to me.

My current boat has a displacement hull, its slow and steady but comfy. What i am considering for future purchase is something with a loo, bunk sitting area for the kids, a small sink and kitchen area so that a bacon sarnie can be made, and for me...........somewhere to put me rod, sit back, relax and enjoy some quality time with the wife and kids without a tv or games console insight.
I have limited funds (as do most average families) and we also have a caravan, so things have to be balanced, so no point buying the most expensive boat, only to find we can not afford to maintain it to a safe standard.
Our caravan has a service every year, and anything it needs it gets. Simple.
If a big boat is going to be big and expensive to buy and own........i'll stick to my ickle Sea Nymph lol
thanks
Stuart
 
I've been through this learning curve over the past 20 years. I started with a 22 ft sailing yacht which had 2 bunks, a galley, and a toilet.

After sailing single handed from Southampton to Hartlepool I thought "too slow" so bought a 26ft planing sports cruiser. She ran on petrol. The dealer told me 4 gallons an hour. She was beautiful, and like a modern caravan on water. The trouble was the dealer lied, she did more like 16 gallons an hour and we could never afford to go to sea. We'd take her out of the lock, anchor up, and then bring her in later. This usually still cost £100 in fuel.

We couldn't wait to sell, and dreamed of a diesel version. We next got a semi planing diesel 30 ft boat. For twice the money of a petrol boat you get something much older and tired. Nobody wants petrol so they go cheap. This was back in the days when red diesel was cheap and could be used for propulsion. This was a good compromise, but she was more problematic as older. She would do 25 knots with reasonable economy, though still expensive. Power boats drink thirstily.

We next went to a 40 ft liveaboard power cruiser, she was lovely to liveaboard but fuel costs stopped us from doing any real cruising.

We've now come full circle to a 48 ft sailing boat (the circle got bigger) which incidentally does the same 60nm for 25 litres as the smaller sailing boat mentioned earlier.

If you're on a tight budget get a trailer sailer is my advice. Don't skimp on safety equipment else your day sails will be haunted by the thoughts of "what if?"

Hope this helps ... Fizz
 
Sea boat

The short answer is the bigger the better. It is possible to make a small boat very robust for really rough conditions. However it still must have power to get away from lee shores etc.
The biggest problem is that crew are usually not nearly so robust as the boat in rough water. Hence bigger is kinder on crew. A boat capable of speed and power to get home in rough weather then may have ultimate safety benefits.
The problem is that a planing hull may exhibit high speed on flat water is limited to low speed in rough conditions just like a displacement hull but with the disadvantages of unsuitable hull shape.
As a matter of interest I have this weekend been involved in getting my little sailing boat checked out for Cat 5 racing at night. This is a safety standard for boat and gear less than but along the lines of requirements for ocean racing. I have fitted locks to the front and main hatch that can be operated from both inside and outside along with tie down for the washboards. The interesting part was sat morning when it and other boats were tested for self righting power.
This involved tethering the boat fore and aft and pulling the halyard until the mast came down to horizontal.
We got an ultimate force of 38kg at the hounds at 90 degrees. A lot more of course at 45degrees. It was heartening to see how all hatches open at this stage were well above water line and no water entered.
Indeed it sat up on the gunwhale quite high. Unfortanely this test is not indicative of real life as in a small boat the weight of the crew become quite significant and I know it will get water in the cockpit with 3 or 4 crew on board when she goes over.
The point of all this is that a boat which can be sealed off with self draining cockpit can be very safe in the worst weather. More so if the crew are safe inside and there is plenty of sea room.
I do not agree with one poster who insisted only inboard engines are suitable for rough weather.
Modern outboards can be very reliable and fuel efficient. However they can be unsafe when fitted on a boat with no keel where too much power going down a wave can cause bow to dig in and boat to broach and roll. ( a bit like pushing a single wheeled wheel barrow) Just be careful olewill
 
many thanks for the replies, alot to consider and 'take on board' (apologies for the pun)
One thing alas I doubt i will ever have is sails (stone me if you wish) although i have family members that do, and hiss at the thought of motor power only. However, I admire those that take to high seas and can masterfully operate something, that to me is more complicated than the space shuttle!!

My little 17ft Sea Nymph, is classed as a sea boat.........yeah right!!! Just cos it's called a sea nymph and has a displacement hull does NOT mean it is safe at sea. End of the thames / medway estuary is probably the furthest i'd go, possibly a little more on calm days but that'll be it.

What makes me curious is the vast array of different boats you see tied up, hell i swear one at my local BC is a river cruiser........but who am i to say it's not suitable on the sea?

What is also strange (or maybe i am not aware of) is the lack of control on the water, heck can anyone really just go buy a boat, dump it in the sea, and go forth??????:eek::eek: Seems so, madness to me, hell i am new, but i read and read, ask and ask, then slowly progress with the practical.
Stu
 
many thanks for the replies, alot to consider and 'take on board' (apologies for the pun)
One thing alas I doubt i will ever have is sails (stone me if you wish) although i have family members that do, and hiss at the thought of motor power only. However, I admire those that take to high seas and can masterfully operate something, that to me is more complicated than the space shuttle!!

My little 17ft Sea Nymph, is classed as a sea boat.........yeah right!!! Just cos it's called a sea nymph and has a displacement hull does NOT mean it is safe at sea. End of the thames / medway estuary is probably the furthest i'd go, possibly a little more on calm days but that'll be it.

What makes me curious is the vast array of different boats you see tied up, hell i swear one at my local BC is a river cruiser........but who am i to say it's not suitable on the sea?

What is also strange (or maybe i am not aware of) is the lack of control on the water, heck can anyone really just go buy a boat, dump it in the sea, and go forth??????:eek::eek: Seems so, madness to me, hell i am new, but i read and read, ask and ask, then slowly progress with the practical.
Stu

Stu seems you have a pretty good grasp on the situation except, there is allot of Bull5h1t about sailing, it is like walking up Snowden. Any idiot can do it just some people make it more difficult by going up the vertical bits... Or going up on days where the weather says you should not be there.
 
One thing alas I doubt i will ever have is sails (stone me if you wish)

I certainly won't stone you for that, but remember a sail boat is a motor boat too, with an alternative form of propulsion should you tire of fuel costs and noise.

I think a large percentage of the answer to this question is the owner, and his/her experience. I've seen jet skis crossing the channel, Ancient sailors have crossed oceans in rafts and canoes, and I know one guy who has done 6 transatlantic crossings in a 26ft carvel planked boat.

I don't believe size makes any difference, my 22ft boat in the rough just seemed to bob up and down with the swell and waves, while my 48 ft yaws and rolls in the same sea.

Given the right experience from the skipper, I wouldn't hesitate to go for a jolly in your Sea Nymph provided all relevant safety equipment was aboard.

... Fizz
 
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