<20' Offshore Speedboat - Already exist, or plans?

[Crawford]

Hi folks,

I recently serisously considered the purchase of a 1966 Glastron Jetflite 144 with 100HP period Mercury outboard. It needed some work, but my real reason for walking away was that i was unsure of its useability for my interests.

An american Glastron forum suggested that these speedboats were only really suitable for inshore lakes, which must be close to flat. If there were many such lakes in the south of the UK i would be happy with this, but their scarcity leads me instead to think i will be using it mainly along the bristol channel. Thus, the Glastron would be unsuitable for this.

I've searched to find speedboats suitable for UK (almost) offshore waters, but only really come across the Fairey brand. These seem kinda big.

Other designs i've looked at include those of Donzi and Formula, but whilst these may be seaworthy i find them unattractive and expensive in both initial and running costs.

Aesthetically, i like the Chris Craft designs and things of this ilk - however, these seem also unsuitable for offshore use.

Key Question:

Do boats (or plans) exist for classicly styled (30s-70s eras) offshore power/speed boats that are traillerable (<20') and reasonably seaworthy?

I am seriously considering making something wooden myself - should be reasonably feasable as my family are cabinet makers.......

Any suggestions welcome!

Cheers

Crawf

P.S - Sorry for the rambling background!

[Crawford]

I know i ramble a little in my post, but surely someone has some suggestions!?

[antonfourie]

Crawford, the problem with speedboats is that they tend to have too little V to be able to handle any size wave without slamming, if you are looking to build yourself then perhaps look at a sportfisher hull with your own deck design.

[Crawford]

Certainly true of the Glastron and Chris-Craft lake boats, but Forumula, Riva and Donzi have fairly deep V don't they?

How deep a V is nessecery for "safety" in >8' waves?

[mmd]

What do you want to use the boat for? This will affect the type of hull to have rather considerably. Do you want to just go joyriding when the weather is pleasant, or do you want to do a bit of fishing? Will it be used as a commuter of sorts to take family and gear to a holiday spot on a nearby island? How much speed do you want? Do you want to go leaping from wave crest to wave crest like the racers do, or merely maintain a comfortably fast pace adjusted to the current conditions?

With a better understanding of the conditions of use, us designer types can better suggest what type of boat is best for your situation. I suspect that, for most features at least price, a home-built boat may be in your future, but be prepared for that to be relatively expensive too.

[Crawford]

Hi,

The boat would be used for joy-riding in pleasent conditions, but would ideally also be useable (in an enjoyable rather than just survivable way!) in lesser conditions.

It might be used to commute down the coast of Wales, and i would think a cruising speed of ~30knots would be fine. Picking up speed to 40-50knots would be great if available for short blasts. I appreciate that 50 would require substantially more power, so perhaps the lower estimate is more realistic.

It would not be used for fishing, but sufficient stability to swim from would be highly desirable.

Hopefully the costs would not be too high - we have a fair selection of automotive engines in the family, and probably sufficient timber lying around not to have to buy further.

Cheers

[antonfourie]

Crawford, every hull shape is a compromise, as MMD ask what would your intended use for this be ? Are you going to use it on nice days with the ability to handle a bit of chop when the weather turns, or is this a serious work boat that needs to be able to cope in a gale.

A basic assumption is that you will use it for nice days and be able to cope with some North Sea chop, in that case a V of between 18 - 20 degrees should do the job.

[Crawford]

I am somewhat limited in my ability to answer as i don't know what sort of conditions are typical of the english channel, southern part of the north sea or the Bristol channel.

The boat should be useable in whatever is typical here, at its best in good conditions for these regions, are safe to some extent beyond typical. However, this is a pleasure craft, not for work giving flexibility as to its launch conditions.

I was suprised to read that the Riva Aquarama (or however that is spelt) is suitable for conditions of <8' swell. Is this the case? I did not think these were of particularly deep V design.

Cheers

Crawford

[stonebreaker]

http://www.rbbi.com/links/pbl.htm#power

This is a list of North American powerboat builders. I realize you're in the UK, but maybe this list could give you some ideas? Check out the Hydra-Sports fishing boats - they're made for offshore fishing, which I know you said you don't do, but the smallest one is 18 feet and they have a very nice deep vee hull. Maybe you could have one refitted to suit?

[Crawford]

I'm rather interested in building my own, in either marine ply or hardwood. This seems the best way to get the classic look im interested in.

These all look very impressive, but not really my taste!

Cheers though!

[stonebreaker]

I understand about having the bug to build your own - I have it myself.

[sportcruiser]

Hi Crawford,

You may want to check my design at www.bootbouw.blog2blog.nl. I also intend to use my boat for short holiday trips, a bit of cruising and even skiing. It inclused a bow sleeping cabin, sun deck, etc on a retro 50-60ies look. My design is 30ft, a bit larger than you intend. Sizing it down is an option but that would mean elimating the bow cabin and sun deck. It has a 22deg deep V.

Greetz,

Klaas van der Woude

[rustnrot]

I am thinking about building this one.

http://boatplans-online.com/proddetail.php?prod=MG20

[Adam Younger]

We could certainly supply suitable lines / build details for what you are looking for. Most of our work is for high speed planing and I believe our offshore race hulls and their handling are excellent for UK conditions.

more info at our website

Adam