Playing around with a 10 m trailer cruiser

[marshmat]

We do seem to think alike, Will... the sketches I was playing with earlier this afternoon have the motor box as a sunpad/bench in the cockpit and front-end belt/fittings access through one of the dinette benches. Sketches below are VERY rough (like, 4 minute rough) so please don't laugh....

[fcfc]

I am just comparing the layout sketches with the last dimensionnned drawing you posted ( http://www.boatdesign.net/forums/sho...731#post144731 ).

You intend to have a headroom of about 1500 mm (5' ) in the forecabin and head, and about 1800 mm (6' ) in the saloon ?

IMHO the head look small, around 600 mm (2' ) wide and limited headroom for a boat that will cost over 100 000$ (200 hp + jet drive). Looks much more of a locker than a head.

Why do not us use a pivoting back seat. You put the back seat in rear position, you sit in facing front and make pilot bench. When you put the back seat in front position, you sit in facing back and make dinette bench.
This would allow to widen the head space and give more knee/feet space. ( I am sorry for the english description. I reach the limits of my english skills).


BTW, is a inside steering position really needed ? You will have to match field of vision requirements if you do so. ( http://www.boatdesign.net/forums/sho...013#post109013 )


As a side note, the width of the forward double berth do not match. From the dimensionned drawing, the width at station 3 at the heigth of the berth is around 1000 mmm (3' 4" ) Very very narrow for a double berth.

[marshmat]

The rough sketches I just posted are not really to scale, just concepts....
Interesting idea of using a pivoting bench for the helm, fcfc- our VIA Rail trains use similar pivoting seats to switch between 2- and 4-person groupings. Very quick and easy to do with their mechanism.
I definitely want the helm to be inside the wheelhouse. I've been thinking about a semi-convertible top on the house, much like Ellings and some new Hinckleys have- weathertight when it's cold and wet out, open to the sky on nice days.

[Willallison]

Yes - it's difficult to get a double berth in the bows as you've shown it, without having it located so far aft that it becomes impractical. I'f you're not hell-bent on being able to walk (stoop ) around it, then a vee-berth is often a better solution - except when the bloody pillow falls off the end of the bed!

[fcfc]

I have tried to sketch something similar of your proposal time ago in the O1 thread. Euro trailerable , so sligthly smaller than US trailerable. Really smaller engine. I have found cutting the speed by 2 cut the engine power by 5.

But I have miserabily failed to sketch something realistic and usable. My current impression is that the layout is a very complex and crucial stage of the design and drive all (for cruising boats of course,for racing a bit different ).

For informations, in the last stages of my delirium, before complete madness, was to design some kind of box garboard / box keel / hull bossing to lower a bit the engine. and to put some raised dinette al la deck saloon sailboat above the engine. ( http://www.sirius-werft.de/Bilder/32DS/32DS_Daten.jpg ). But the problem is that the dinette has to extend well past the centerline of the boat to cover the full width engine protrusion and the remaing passage between the dinette and the galley is rather very narrow and is the only place where you have standing headroom.

[fcfc]

Originally Posted by marshmat

...
I definitely want the helm to be inside the wheelhouse. I've been thinking about a semi-convertible top on the house, much like Ellings and some new Hinckleys have- weathertight when it's cold and wet out, open to the sky on nice days.

That is perfectly possible. But the helm inside will practicaly kill the headroom in the head. There was a thread about head up or down in the O1 forum. Steering from inside mandates you to head down, in the forecabin. And you will have very hard time to achieve standing headroom there. If you put head up in the saloon,where headroom is easy, it will mask rear field of vision.

One of the cheating is to have two steering stations. One outside, declared as primary, with the required field of vision. And one inside, declared as secondary. With placards specifying the limited rear field of vision. Beyond the increased cost of dual stations, it also eat precious space both in the cockpit and in the wheelhouse.
The other cheating is to have of big windows in the front and rear bulkheads of the head, protected with curtains when in use. That prevent any mirror or cabinet fixed on the bulkheads. Either in the head or in the saloon.

[Willallison]

fcfc - is complying with ISO 11591 - the field of vision standard to which you refer - a requirement for ALL vessels built or used in Europe? If it is then there's an awful lot of boats that don't comply. Many with the fwd vision, let alone when looking aft.....

The relevant part of the standard, when considering head up/down is this:

5 Field of horizontal vision — astern
5.1 Craft without permanent cabin or other superstructure aft of the main helm position
obstructing vision astern
A field of vision astern to the horizon shall be provided throughout a horizontal arc of 135° equally divided on either
side of a longitudinal axis directly astern from the helm. Vision astern shall be provided without leaving the helm or
controls, i.e. not more than 0,5 m to either side form a seated position or 1 m to either side from a standing position
in craft intended to be operated from a standing position.
5.2 Craft with permanent cabins or other permanent superstructure aft of the helm obstructing
vision astern
NOTE Readily removable obstructions to vision, such as convertible or camper tops, aft and side cockpit curtains, are not
considered as permanent superstructures. It is assumed that, during inclement weather when these items are in place, caution
in operation will be exercised and a lookout will be maintained.
Other means such as mirrors shall be provided to meet the requirements for vision astern specified in 5.1, without
leaving the helm or controls.
On craft fitted with autopilots, the helmsman may leave the helm position briefly to meet the requirements for
visibility in 5.1.

This suggests to me that, for a boat that meets the std, you are't necessarily confined to the head down arrangement. Just that there is a further complication to consider. The problem with locating the head down is - as you've alluded to - in order to get sufficient headroom, the overall height of the vessel must be increased significantly, increasing the weight, raising the CG etc. The upside, however, is that you gain a far more open feel to the main cabin / cockpit area(s)

[marshmat]

My interpretation of the standard is that if the view aft from the helm is obstructed (ie, by the head), you simply have to add mirrors and/or CCTV monitors to ensure you can see what's behind you. To be honest I see very few vessels, anywhere, that fully comply with the standard at all helm stations.

[Willallison]

You wouldn't be required to comply with it in the States anyway would you Matt?

[marshmat]

Canada, and no, I wouldn't be required to follow an EU standard.... but having studied ergonomics extensively while on the solar car team, I intend to do a much better job with visibility and comfort than was possible on that project. I'm pretty sure this one will meet the standard in most if not all respects.
More drawings coming tonight (hopefully) now that moving is more or less done.

[Willallison]

Originally Posted by marshmat

Canada, and no.....

Oops, of course, sorry...

[marshmat]

As promised, a general arrangement and a profile.
Still very very rough of course but you get the idea....

[Mat-C]

'nother thought. As you've shown it, the cockpit doesn't appear to be self draining...?

[Willallison]

hmmm - got me a little confused. Does this mean that the head will have a raised section where the engine box protrudes in? If so, what will be above it? I guess the basin could go there.
You could lower the overall height by lifting the step at the helm. This means there is no longer standing headroom there, but allows the helmsman to poke his head out a hatch directly above for improved visibility or comunication with deck crew etc

[marshmat]

As you've shown it, the cockpit doesn't appear to be self draining...?

She only draws about 30-35 cm at rest- the cockpit sole is 40 cm above the keel, so with appropriate one-way flaps on the scuppers it could self-drain.

Does this mean that the head will have a raised section where the engine box protrudes in? If so, what will be above it? I guess the basin could go there.

Yep; basin above motor would seem to make sense, unless there's something else that goes in the head that needs to be elevated. I was thinking just a basic head and a small basin. The idea is that this is a fairly large, but uncomplicated, trailer cruiser- if it ain't there I don't have to shell out cash when it breaks.
Should a boat this size have porcelain tile, bidet and a 28-jet Jacuzzi? (OK, the Jacuzzi can stay on shore....)
I think I'd rather have standing headroom at the helm and more window area; she is only 2.5 m (8 ft) overall height which I don't think is excessive. Thinking of how to get that retractable-hardtop thing going, sort of like an Elling E3 has.