Your Opinion on Cathedrel Hulls?

Member Joined: Oct 31, 2009 Posts: 30

Any comments welcome, good/bad
Thanks

Posted: Wed Aug 25, 2010 1:49 pm

I always go for a catheral hull due to the fact that if the weather turns nasty you can get back in quick also same applies going out, you can be on the fishing ground in no time, It has to be said however a clinker built hull is more stable.
Cheers
keith big grin

Member Joined: Oct 31, 2009 Posts: 30

Hi there, thanks for your reply, do you have a cathedrel hulled boat? Do you think cathedrel hulls can take a bashing from the weather, good for offshore?
Thanks
John

Posted: Wed Aug 25, 2010 8:07 pm

Cathedral hulls can take punishment but as stated in my previous post they are designed to beat a quick retreat when bad weather starts. I sold my boat see http://www.sea-fishing.org/ftopic-13428-0.html Rabbit2. I have now 2 small boats for fishing in good weather or the estuaries and shelterd bays.
Cheers
keith big grin

Posted: Wed Aug 25, 2010 11:05 pm

Johnn wrote:

Hi there, thanks for your reply, do you have a cathedrel hulled boat? Do you think cathedrel hulls can take a bashing from the weather, good for offshore?
Thanks
John

Only if they are well built and relatively big ... Offshore 105, very nice, no sweat ... 14ft glorified speedboat ... you wouldn't want to go too far out and you'd want to be sure of good weather. There are a number of pros and cons with fast hulls and they require you to behave accordingly.

Although they are fast they are not particularly stable in the rough, especially in a short sea and the rough weather means you have to slow down considerably and lose all your advantages ... that in turn means the boat no longer planes, it takes a lot of force to push it through the water and you therefore need to burn an increased amount of fuel to get home. I have on many occasions come across owners that got caught out and ran out of juice simply because they did not do their sums on the fuel or because they left no safety margin for increased fuel consumption when off the plane.

The other point in this situation is that when you are off the plane and down in the water your freeboard is reduced and you are much more vunerable to beam on waves and wash - this means you are vunerable to capsize and can take on a lot of water in certain conditions.

The other point (and this is a feature of every planing hull I've ever come across) is they become incredibly hard to control in a following sea and can be downright unstable if caught out in the weather ... I would say that being a long way from home in a small planing hull with a following sea is probably the most dangerous situation (other than powerless in a shipping lane) that I can think of.

One final thing i feel obliged to say, and i don't mean this as an insult or a put-down although it will most likely been seen as one by some. If you have to ask a question so basic as to what are the capabilities of a certain hull design then you really do not possess the level of knowledge required to venture safely offshore and doing so may well put not only your own life at risk, but those who may well have to come to rescue you. As I say, this is not an insult, knowledge can be gained (the RYA day Skipper course comes to mind) but once your life is lost so far as I am aware theres no second chance!

Posted: Thu Aug 26, 2010 6:49 am

Words of wisdom indeed.
Cheers
keith big grin

Member Joined: Oct 31, 2009 Posts: 30

Just on a off note, would it be econimical to go at displacement speed (3 - 5 knot) for a abit? on a 40hp?

Posted: Mon Aug 30, 2010 9:37 pm

Johnn wrote:

Just on a off note, would it be econimical to go at displacement speed (3 - 5 knot) for a abit? on a 40hp?

Depends what you mean by "a bit" really .... the distance you cover for a gallon will be way down than what you could achieve on the plane because you will be counteracting a lot of drag on the hull. Depending on how heavy you are laden as little as a thou of revs can be the difference between wallowing around like an old bathtub to flying along at 18 knots across the surface so not bringing the boat up is generally a waste of a fair amount of fuel over long distances.

There's obviously times when you don't want to fly along (ie searching for a mark or a shoal of fish on the fishfinder), and times when you can't (such as rough weather) but its important to do your sums on the fuel ... calculate your safety margin for getting home in the worst case scenario (ie off the plane, against the tide in rough weather) and you don't end up calling out on the radio for a lift.

Important too to match the engine to the boat ... people think that a smaller engine is always the most economic option and it isn't ... nothing worse than a planing hull that's underpowered as it generally means the engine has to be at flat out all the time and thats a juicy way of running them ... better to be at cruise ... its more economical and puts less stress on the engine.

Just out of interest are you looking at any particular boat or just generally cathedral hulls?

Member Joined: Oct 31, 2009 Posts: 30

Hi there, I am looking at a Wilson Flyer,
Thanks for your previous comment.
John

Posted: Mon Aug 30, 2010 11:09 pm

Johnn wrote:

Hi there, I am looking at a Wilson Flyer,
Thanks for your previous comment.
John

Yes been on one regularly ... a good few years back. Good boat (17 - 18 ft?), big cuddy as I remember but it needed a fair engine to push it properly as it was fairly hefty and it was a bit of a pig to handle in a chop and had very low freeboard. A wide beam though so lots of room to fish.

I think they did some later versions with a lot higher freeboard and they used to sell the hulls with various cabin configurations so they come in all sorts of flavours from about 60% cabin to a tiny cupboard at the front big grin

Safe enough basic design and we used to push out a long way on that type of craft ... but I hasten to add you still have to know what you are about.

Member Joined: Oct 31, 2009 Posts: 30

Hi there, just one more thing, This may be a stupid question, but is it possible to fit a diesel inboard engine on a 17-18 ft look a like of a wilson flyer?
thanks
John

Posted: Tue Aug 31, 2010 5:39 pm

Johnn wrote:

Hi there, just one more thing, This may be a stupid question, but is it possible to fit a diesel inboard engine on a 17-18 ft look a like of a wilson flyer?
thanks
John

In theory I would have thought yes ... I've seen a few of these type of hulls fitted with inboards and water jet propulsion though no idea what exactly is entailed. I would assume you would need appropriate engine bearers put in place and depending on the exact design you might have some complications over prop-driven set ups but I suppose nothing is insurmountable. Downside might be that you would lose space to an engine box and it could be difficult to set up for trim as they are generally designed for weight on the transom.

Best advice is to ring a couple of marine engineers and ask about practicalities .... I'm not the greatest boat engine man in the world and all my experience is outboards.

Member Joined: Apr 12, 2009 Posts: 93

I have a 17ft Wilson Flyer with a Mercury 50hp ootboard, and it's the best..... It's very stable and quick with 50 horses on the back. It has loads of fishing space and a cuddy if it rains. A fab boat big grin

Member Joined: Jul 15, 2010 Posts: 7

HI ,
I have a 18 ft Birchwood cathedral hull powered by a 35 horse merc..It is moored on the clyde coast, which at any time can become nasty{short sea big wave 5ft plus }.This is only my second season on salt water and am engoying it greatly.Common sense a bit of experiance and reading forums like this can be a great help.
Regards
John.

Member Joined: Oct 31, 2009 Posts: 30

Thanks for your message, what kind of speed do you get with your 35hp
Thanks