List Of Sacred Goals....

Right, you lot....

Since it looks like I have been asked (well told almost ) to moderate, organise or something - this is the next bit:

Following the comments on the Power cruising for... thread it seems that everyone would happily go off and design a different boat - hence the polls!

I heartily agree with Tom, Gary and the others that we should nail down a solid description of the application, type, budget etc.

For this time around lets go with the system of an option list for 4 or more "Boat types" such as the 2 already posted. A few more like this, a few days to give everyone a chance to discuss, post, design and vote and then we will have our project outline. THEN the big question will be selling price/budget for the winner... this will influence all sorts of things!

So as a reminder so far we have:

Option 1 Trailerable, couple, home build $
1 Coastal hopping
2 Trailerable
3 Range 300 miles
4 Crew, 2 minamum
5 Price range, under 50K US, for home built.
6 Must be able to carry on a normal conversation at 3/4 throttle.

Option 2 Tough, family+friends, pro build $$$

1.Capable of handling a wind against tide/current situation (say the Gulf stream at 2.5knts, against a solid f4) -which I seem to remember is medium nasty.
2. Not trailerable, lives at the marina for long season use (see 1.)
3. Range of 600 miles minimum - spending time at anchor rather than on the dock.
4. Sleep 4 in comfort, with space for a couple of kids in the bilges if needed.
5. Designed for Semi-custom production with a set number of options by a relatively small yard.
6. protected prop(s?) in case of umm.. "operator error".


Will, Tom, Steve, 8knots,Tad and others have some great ideas for what we should be designing to - how about 6 points as above for them (thanks to Gary for the format!) ... Will and/or Curtis - want to work out 6 points for an "express cuiser"? Steve and/or 8 how about a motor-sailor? Tom - would you get 6 points to outline a cost effective boat - These are all just suggestions off the top of my head so please dont take offense!

As long as it fits the description of "Coastal hopping for a week" decide your own sea conditions!

Cheers

Paul

 

Thank you Polarity, you are doing a great job of managing all this.

The first question I ask when someone mentions a new powerboat design is, "how big and how fast". I would respectfully suggest that proposed speed will inform every design decision beyond the initial size question.

We have two sizes proposed above; option 1, which is a trailerable boat, would probably be somewhere between 19' and 25'. Option two would be somewhat larger, due to the longer range and heavier load.

Now let's look at speed. For the smaller boat we have a proposed range of 300 miles. I understand that the range figure mentioned was to indicate fuel load, just for fun let's look at it as weekly range. Use of the boat is to be along the coast for a week. If our boat is to cover 300 miles in a week, with one lay day, she's got to cover 50 miles per day. Under way time of 6 hours per day equals 8.3 knots. That's one boat. Now if her weekly range was to double, that is she would have to travel 300 miles out and 300 back, maintaining 17 knots for 6 days out of seven. That would be another boat! In fact a totally different design.

It could be a similar question for the larger vessel. Six hundred miles in six, six hour days is 17 knots. But if one wanted 1200 miles in the allotted week, speed goes up to 33.3 knots! That would be a substantial boat!

Now in my week I would like to go have a chat with 8knots. Say we will meet for coffee in Anchorage. It's about 1300 miles away, across the gulf of Alaska, that's along the coast , right? That's a total of 2600 miles in 6 days. If I run 10 hours a day that's an even 40 knots. The first leg is 480 miles to Prince Rupert, second leg 300 miles Rupert to Sitka, then the last 520 to Anchorage. Then return.

What sort of boat could do that? I'm thinking a big hard bottom inflatable. It would be trailerable, have a wheelhouse and accommodation, and carry lots of fuel! Is it possible, maybe, I don't know yet.

OPTION #3 Maxi Trailerable Hardbottom Inflatable
1 Very fast coastal hopping
2 Range 600 miles
3 Crew 2-3
4 Welded Aluminum Construction
5 High speed in all weather & in darkness.
6 Small shop one-off, CNC kit, moderate $$
7 Diesel Waterjet


All the best, Tad.

 

WOW Tad,
Now thats out of the box. If you take that trip can I come along? I think this next poll will be fun.
Gary

 

Hi TAD and everybody else!

TAD, your option 3 looks quiet interesting. One thing that I am focusing on in my designs to come is environment. And as we all know a boat at high speed is not the most environment friendly concept. Can that be a point under your option 3 as well ? I think that will be a big focus on that in the future. (Air lubricated hull, low friction, lower power same speed )

Also we have the material that should be used for the design, can it be recycled and so on …

Just an Idee to get a better market potential

Br
Micael

 

My one hour sketch ...

...of a Ribish idea in response to Tad's option 3. I just realised I didn't include the sketch. See the next post... (bummer).

I just had to do it!!! Even though i primarily draw sailboats at this stage a Rib sounded so interresting I just had to.

I threw this together quite quickly just to see what you all think. It is not ready by any means. It won't be for quite some time since I'm still just a beginner at this.

Comments and critic welcome. As for HP requirements and more details I'll leave that to the people who really knows about it

 

The sketch...

LOA: 10 m
Lwl: 8 m
Beam: 3.35 m

 

P.S. The ability to add an attachment when editing a message rather than just when creating one and to add multiple attachments is coming in a month or two - I would add this to 2.2.4 but 3.0 is right around the bend...

 

Now thats really cool...

How far away have we come from the first 1 hour sketch!!

Tad - brilliant idea! - great 6 points too. That is some usage of the words "cruising" and "coastal" - just the kind of challenge we need!

Great sketch Eric- better have a very comfy seat (s) and a set of padded straps for a 35 knot trip across the gulf of Alaska though - at least you would keep the props dry!
have you seen http://www.ribmagazine.com/ ?

Micael: how about an environmentaly friendly 6 points for an Option 4?

Re speed - I had in mind that someone might post an "Express - cruiser" type option...

Cheers

Paul

 

PS Thanks Jeff

For the redirect of the end of the last poll.

Paul

 

I wonder if the sense of the group is leaning away from a displacement cruiser as an acceptable option. As Seinfeld would say, "Not that there is any thing wrong with it", but most posts seem to be leaning toward speeds higher than a displacement hull can reasonably achieve economically.

If the group agrees with that, then the direction is narrowed a bit more.

A question for Tad And Erik. What is the ultimate advantage of the inflatable RIB?

Granted that it provides survival floatation in just the right area to maintain a safe hull attitude for the crew in the event of a catastrophy, how does this differ from a rigid hull that provides compartmented floatation in the same places? I suspect that the answer is that no one could resist keeping this "unused" space as flotation and would sacrifice it, either in the design stage or later, during use, to living or storage space. Looking at the outline of the space that Erik's boat occupies, it's clear that this is a small boat for it's size. Would either designers or buyers accept that in a non RIB boat?

I like the boat as a concept but would not want to cruise in that fashion. Maybe when I was much younger, it would have had greater appeal to go bashing along for day after day like that, but not now.

I kow that Tad has designed boats that fit into the categories that we talk about. How about some vital statistics, including performance and fuel use on some of these Tad?

I'm enjoying this but have only the haziest idea of how to attack the costing assignment that our leader has given me. I think I will wait until there is something more solid to go on.

 

Not to worry Tom my heart follows my belly, that would be displacement. I like to drink my coffee underway from a cup not a straw. If we end up working on a gofast. I'll still learn something.


Gary

 

Displacment for shure

Personally I'd definetly favour a displacment or perhaps semi for cruising.
Tad's input "forced" me, I just had to do the sketch of the RIB as I felt some ideas bubbling up inside me.

Tom, you're absolutely right that no one would accept that llitle space on a boat that big if it wasn't a RIB. I feel that a RIB is the way to go if you really need to go fast.

But for coastal hopping for a week I'd definetly go displacment. Enjoy the ride, have some coffee in relative "peace and quiet".

Actually in my personal view a boat with low drag, small draft, good fuelefficiency, low engine sound and good interior space at an affordable price would punch my ticket. Top speed would not be my primary concern. After all it's about a vacational boat, what's the hurry.

 

Love the RIB idea - my parents (well into their 60') rarely take their 36 foot displacement cruiser out anymore - prefering to cruise at 40 to 45 knots (60k flat out) in their converted dive poachers boat (no they weren't the poachers!). But my experience from that is that unless you want to more or less camp aboard, that style of boat doesn't really fit in with our "one weeks coastal hopping" unless you want to hop off at the end of each day and go stay somewhere ashore.

So, here's my ideas for a medium to high-speed coastal cruiser:

1. LOA 30 to 35 feet
2. Range 400 to 500 miles at a cruise of 20 to 30 knots. Still economical at displacement speeds as conditions may not always allow higher cruise speeds.
3. Accomodation for 4 - possibly 2 more occaisionals on convertible dinette / sofa. Ability to cruise without the need for re-supply for the full "one week cruise".
4. Designed for semi-custom production - but still possible for owner/builder construction.
5. Light weight - economical to build, power and operate.
6. Ties points 2 & 5 together - Powered by 2 large (200+ hp) 4-stroke or dfi 2-stroke outboards. They are light, powerful, and economical to buy and operate. The installation of a single o/b possible if lower cruise speeds considered.

 

No one is going to suggest a power multi. There must be some interest out there for a 30' cat with a nice wide bridge deck.
Gary

 

That's an excellent point - reading this I got thinking so much about the semi-displacement solutions and 8knots beautiful cruiser, that I was focusing on what was already here rather than what might be missing. I think there's a lot of room for a really graceful smaller power multihull...

I was going to reply that a power multi might be providing a solution before the question as a specific hull type could fit any of the three existing sets of criteria, but now that I think about it, what has really brought this thread to life are the ideas which have been injected into the discussion along the way. And I think that having some complications and glimmering ideas on the periphery makes a much more interesting project than straight line problem solving. It's really interesting to see the direction this takes each day and the new jogs along the way...