Buttocks

It is all about the vocabulary and the correct definitions of said. If we dont say what we mean, we wont mean what we say...as the saying goes..

So, what are the distances involved from point A to pint B?
What is the minimum speed required, if any, in going from A to B?
What is the maximum payload you expect?
Do you require any cabin or accommodation, or just an open cockpit etc?

These are basic starters....in your SOR.

 

Ah. I'm learning the appropriate vocabulary. This will a 25' by 10' work/commuter. On the Sunshine coast around where I live, there are countless small islands where folks with far too much money need houses built. Tragically there's no accommodation there for workers, and minimal ferry service. I'm going to drive it like a tradesman's truck, not a donut burning yob. But the distances can be long, so it needs to move. It needs to carry heavy loads while doing so. And it needs to be something I can rough it in for a few days at a time. In my youth I was a combat engineer, so my idea of roughing it can be fairly rough.
Mr E, that was the direction I was thinking. Lose some aggressive turning ability, gain some load capacity. Fair trade.

Ad Hoc, I must confess I didn't read the first link you provided in sufficient detail. Around paragraph 35 or so (he did ramble on! Must have loved the sound of his own voice) in Hickman's patent application he discussed that issue of lost lift from the tunnel to the chine surface. He proposed a series of steps so that each area of chine was always descending, making lift, and adding a fence to reduce lateral flow out of the tunnel to the non-tripping chine surface. And that's a lot of extra building complication. He was selling boats on the basis of being the fastest thing on water on the east coast. I just want to get from the lumber yard to the job site fast enough to put in a profitable days work for my crew and I.

But I was serious when I suggested accelerometer work to Mr Efficient. There's missing lore here. We should know for sure exactly what the numerical values are. I'm going to give up about a thousand hours of highly profitable time. I

The distances will be on the order of 45 nautical miles. I’d want to cover that in no more than an hour and a half. Load is likely to be 1100 kg, to be added or removed daily, so that’s not water or food or fuel. At least half the loa must be dry accommodations. Although a port-a-potty and a camp stove are adequate amenities. Provided my birth is dry. Full standing headroom necessary only at helm.

Naturally much greater distances occasionally. Occasional heavier loads. Frequently half that load.

 

So that's 30knots then!

Is that hand carry on load or craned on via the shore, or do you wish to "drive it on".. a-la landing craft style?

Ok..that fixes accommodation and deck space.

Ok...so endurance = more fuel and as for heaver loads = allow for overloads = high displacement.

Engines = inboard or outboards?

 

30 knots cruise in average offshore conditions is ambitious, 25 would be far easier to achieve for a boat that size and without blowing the budget out, but even that is difficult to reconcile with heavy loads.

 

Aaahhh... Mr.E... you've jumped my gun!

My question is related to the area of operation...i.e. is it in the San Juan Sound in that sheltered region, or, is it on the ocean side?

 

Your SOR makes me think about the numerous water taxis operating in the venitian laguna, in particular the shuttle service between airport and Venice hotels, usually 30 mn at high speed, with 5 to 10 tourists inc. their luggages, so an average 100 kg per person. They worked hard all the day round, very reliable and adapted to their programme. The Laguna is not always flat sea, there is a none negligeable fetch + the numerous wakes of the other bigger boats to cross. Here is the most common model, the version called convertible workboats, model A offering 16 seats, build by Serenella cantiere motonautico based in Morano. I have not the exact features, I think about 9 to 12 m long, 2,2 m width :
Convertible Workboats http://www.cantiereserenella.com/it/P/convertible-workboats-6

 

When you think of these sled boats, they date from the era when most planing boats ended with a flat, or near-flat bottom at the transom, it is more or less one of those old boats split down the middle, and stuck back together, just the other way round. It would be equally possible to do something similar with a deep-vee monohedron, but back in those days, they were not around. Maybe in that latter case, you would be able to fit spaced twin engines, without the aeration of propeller issues.

 

I'm going to build it with proper engine beds, and a proper outboard well. We'll see what the budget allows next spring.

 

Indeed. Many of the descriptions I've read of failed sea sled project were doomed to failure, because the builder lacked the intelligence to note the issue with water/foam/air in the center of the transom, or the attention to notice that Hickman used twin surface piercing propellors before 1920. Instead they used a single outboard, and were baffled that it performed poorly. I'm baffled that they managed to tie their own shoes.

 

Dolfiman, those look so charming! And the simple accommodation plan is very informative.

 

Ad Hoc. It would generally be tradesman's tools or residential building supplies, so generally hand loaded.

 

Ad Hoc- forgot to reply: the sheltered side between Vancouver Island and the mainland.

 

Why reinvent the well used wheel that satisfy many of these issues.
A quick internet search of vessel suitable for this duty exist, such as this or this.

It appears you are trying to crack a nut with a nuclear warhead. The old adage of KISS applies here.
A simple flat bottom boat with a small amount of deadrise is all you are after. Any typical landing craft type of boat will more than suffice, in that sense.

Do not fall into the trap of overthinking this...it is basic, not rocket science.

 

Those are fantastic. Compare them with this: 2002 Custom Dropbow https://www.welcomeaboardsitka.com/boat/2002/custom/dropbow/1047/

I'm going to confess to an emotional bias here. I've badly wanted a Hickman Sea Sled since the Woodenboat article of Sept '90? At the time I was building a Colin Archer double ended lifeboat, 47' by 11', if I recall correctly. Which I was delighted with, right up until I wanted the Sea Sled. Funny the things that get inside our heads. That was so long ago, I wasn't even bald yet. Still fit into my combats. Finished the Colin Archer, by the way. Long gone now. Still want the sled.

So I absolutely agree... those boats are a licence to mint money, in the right hands. But my heart is a little inverted V shaped. I hope you'll forgive me.

 

This is the "passion" side of the Art....but on the clients side, not the designer.
No one can argue with your passion, it is subjective by nature and thus to the point of illogical to others.
Thus, once you YOU decide what you want and it full fills YOUR requirements, the rest is background noise and not worth addressing. Your SOR is the key to your success and pleasure. The fact another hull may offer 0.0001% better resistance or seakeeping etc or someone else doesn't like your selection etc...is missing the point of client-designer relationship and that boating is always subjective pleasure and passion that cannot be understood by others beyond the objective facts. My wife doesn't understand many of my obsessions...doesn't mean she wont accommodate them!