Westlawn & Cruising World Announce a New Design Competition

1000 Word Description

This was a real challenge to stay at or near 1000 words in the 'description of the design'. (Contest Rule:The designer must submit a clear mission statement, explaining the goals of the design and how these goals are met. Maximum length of this statement is 1,000 words)
I'm not that happy with my essay in this 'outline form', but it was the only way I could point out all of the items of interest I wanted the judges to see.

Westlawn & Cruising World Design Contest
(Essay)​

MISSON STATEMENT: Create an innovative, yet practical vessel capable of exploring the world under sail, either in private ownership or charter, with small crew.

The design of a modern offshore sailing yacht should take into account the older age of the population having the means and time to go long range cruising. The long ignored ‘MotorSailer’ concept should be a prime candidate for consideration.

Motorsailers are not a popular subject these days. Those old traditional, stoutly-built vessels, with a hefty engine(s), were necessarily compromised in their sailing and powering performances. The multihull platform holds great promise to modernize the motorsailer. Long slender hulls of the catamaran vessel have proven real efficient to push under both power & sail.....not only efficient, but not limited to slow traditional displ/length hull-speeds. Just what the motorsailer needs....far less compromised increases, both sail and power performances, while maintaining economy of operation that allows for long-range, and remote area capabilities. In light airs, running one engine often is all that is needed to generate an apparent wind that allows the sails work harder, and the combination can provide much better results than either motoring or sailing alone, …….sailing synergy/harmony, the motor taking over in the lulls and the rig taking over in the puffs.


SQUARE-RIG: The rig chosen for this motorsailer is pure innovation itself, having proven itself on the recently launched ‘Maltese Falcon’. A modern day square-rigger, that happens to possess some very favorable characteristics for use aboard multihull vessels:

• · Optimum (renowned) parabolic aerofoil shape
  
• · Sailcloths can be light-weight & low-tech due to low-loads imposed by extensive ‘square edge support’ by DynaRig’s yardarms
  
• · Non-heeling multihulls experience difficulties keeping ‘aerofoil-shaped sails’ in light-winds,…mitigated by yardarm’s support & lt-sailcloths
  
• · 3-4 panels in height with douseable (reefable), upper, hi-leverage sails
  
• · Topsails of extra-light sailcloths could offer ‘blow-out protection’ in microburst squalls. Meanwhile their superior area/height promotes light-air performance.
  
• · Very considerable stability under ‘course sails’ alone. Storm trysail possible.
  
• · Only 160-degree mast rotation needed, thus headstay and backstay support possible for rough conditions.
  
• · Balance center remains centered upon reefing
  
• · Automated, single-handler for older couple, or charter captain. No winching

This free-standing mast does not exert big compression loads, but mastbase needs considerable bending and torque support. This is provided by the X-structure formed by the athwartships ‘spaceframe’ bulkhead, the longitudinal nacelle & front-frame combination, and a reinforced arch built into cabin-top. There’s a possibility of sealed mast floatation. Finally a unique ‘running backstay’ is envisioned that would alleviate some bending loads at the mastbase.

ASYMMETRIC CENTERBOARDS:
Superior tacking, leeway reduction, and balance could be attainable with optional nacelle-mounted centerboards.

An edge-on flat plate is located down the centerline of the vessel acting as a rib to strengthen the fore-to-aft rigidity of the vessel (weaker characteristic of catamaran). A tow bundle of carbon fiber (kevlar, PBO) is laid along the bottom edge to produce a ‘bottom truss structure’. On either side of this plate/nacelle two asymmetrical centerboards are mounted with their flat sides up against the nacelle, and rotate on oversize diameter bearings. Only one board at a time is lowered, possibly linked together such that the act of lifting one automatically lowers the other. Both could be rigged to 'kick up' upon hitting any solid object, or shallow cruising.

Several advantages to an asymmetrical shaped centerboard;

• · Requires less surface-area (smaller board) to develop a leeway reducing force
• · The boat itself does not have to be sailed at a skewed angle of attack to develop the 'board's lift' (leeway reducing force)…resulting in less leeway.

Drag forces are on the centerline of the vessel, producing minimal turning moments about the center of the vessel…improves the tacking capabilities of the square-rigged vessel.

Front of this nacelle/plate could be configured to act as wave splitter, attacking the formation of those peaky waves under the tramp areas that eventually slap the bridge deck underside….slice those waves down a bit. A fairing could be added to nacelle.

Maintenance of this board system, particularly in remote cruising areas is much improved. No need to haul-out to repair CB problems, or bottom paint hull-mounted trunks and boards. Everything,…cables, bearings, and boards is all above the load waterline.

Eliminating board trunks in the two hulls results in greater watertight integrity, and reduces initial building cost.

HULL SHAPES:
Long slender hulls are key factor…never below 12-to-1 slenderness ratio.
Two offerings:

• · Lighter-displacement semi-circular bottoms offer better sailing attributes, but less volume for ‘cruising amenities’
• · Heavier-displacement ‘canoe-sterned’ Tennant type will tack slower, but carry greater loads

PROPULSION:
1) Adopt the latest ‘Rim-Driven Propeller’ technologies:
…reference http://boatdesign.net/forums/showthread.php?t=9432

• · Smaller diameter than prop counterpart at equal power densities
• · Tucked close under the hull skin for less draft and more keel-protection
• · Located forward away from the transom pitching
• · Partially retractable in shallows,…fully retractable under sail
• · Propulsion unit contained in accessible ‘waterbox’, & potentially serviceable without hauling the vessel
• · Less nosey
• · Less susceptible to fouling lines, etc
• · No reduction/direction gearboxes required, instant fwd/reverse
• · Phenomenal maneuverability, joy-stick operable (real plus on gamefishing version)

2) These rim-drives are electrically driven, so they would require some portion of the latest technologies associated with ‘Diesel/Electric Propulsion’:
…reference http://boatdesign.net/forums/showthread.php?t=9310

• · Diesel/Electric power generating units preclude need for additional ‘auxiliary-generator(s)’….fewer engines onboard.
• Versatile power options…entire vessel could be powered by:
  a) 1 big main-unit,
  b) 2 equal-size units,
  c) 2 unequal size units, for high/low power operations
• · Considerable electric power available would provide for all auxiliary equipments and sail furling operations

3) Conventional propeller propulsion might be augmented with Steyr engine/generator combo-unit(s) to dispense with auxiliary generator units.
________

She could be a real fuel-sipping machine with considerably less fuel weight to haul or propel around. Under sail she could make 18/20kts. Under power 25kts. Range…unlimited.

She could skim over depths as little as 4'. Explore those rivers, mangroves, coves, lagoons. Dive or fish the flats and the reefs from the Bahamas to the Pacific atolls.

This could be the ultimate Motor/Sailer… a passagemaker for your contest requirement’s, “serious cruising under sail”.




[1044 total words, less the title words, signature words, and these words (30) = 1014 words]
.

 

Brian the boat did not have a name as such just code number C1760.
I will post a feature list soon but here is the interior plan and profile, had to do it in three pic’s

 

looking forward and hope to see some more ideal cruiser designs posted here

 

That is quite a unique layout bknautika. I will have to make a few prints and study the headrm of the dbl cabin below the cockpit. Not so easy to picture at first glance.

I sent the same wording as at my posting #9 to Cruising World magazine's 'mailbox', in hopes they would print it and let the other contestants know of this forum subject.

I would also ask Dave Gerr, or another party to this contest to please inform the other contestants as well.

The fact that this subject thread is 'hidden' in the Education subheading rather than in the more general Boat Design heading doesn't help in its visability.

 

Brian here is the deck layout and a sectional view through that aft cabin
C1760
Mission statement.
The boat is to be a contemporary design with a medium to light displacement hull. Its to have an easily handled sail plan set up for short handed sailing by one or two people with out the need of help from a crew or guests.
The boat should be able to be cruised by two people for up to a month with out provisioning; it shall have sleeping accommodation for four with provision for an extra two on a casual basis.
The boat must be good for relaxing and entertaining guests both at home port and at its destination.
Principal Dimensions (metric)
Loa 17.6 m sail areas Jib 30.7 m
Lal 16.5 m Main 100.5m (roach included)
Beam 4.95 m Mizzen 35.8m (roach included)
Bwl 3.7 m Spinnaker (asymmetrical) 146.5m
Draft 2.65 m Code sail 109m
Displacement 19500 Kg WS 64.8 m
Ballast ratio 42%

Hull/deck: Cored grp
Keel: fabricated metal with lead bulb
Keel attachment to be by tab and slot into hull. Raw water intake to be built into the trailing edge of the keel and piped up through the keel tab to wet box for distribution.

RIG: Main. Gunter rig (modern version “the sliding Gunter”) Curved yard slides up on mast track. Some possible advantages of this rig, curved yard shape gives better elliptical sail shape, small section of yard becomes leading edge of sail, no wind shadow from larger mast section. Designed flexibility of yard gives some automatic gust response. Reefing sail also reduces mast CG. Shorter main mast enables smaller mast section due to shorter panel lengths. Single spreader rig can be used reducing windage. Shorter mast enables access to area’s, under bridges not normally available to a yacht of this size. The yard allows for a good sail aspect ratio for a mast this size.
Jib. Self-tacking blade. Small sail can be held onto up into the wind ranges, less sail changes. Light air sails can be code sails flown from the bowsprit. Asymmetric spinnaker for down wind.
Mizzen. Mast is an inverted squared off U shape made of an asymmetric section in either carbon or fabricated aluminium. A track at top and bottom enable stay to be moved athwartships. This enables mizzen to be moved into clean air away from main, also the luff of the sail has no mast shadow. The movement of the mast to the outside removes the obstacle of a centre line mast, free up the cockpit space. Also there is less compression on the hull from standing rigging. The mast could be filled with foam, which would add to the AVS in the case of knockdown.

Deck/cockpit. All control lines lead aft to winches clustered around helm stations. Cockpit can have table up but still have walk through access. Rear boarding platform is large and can act as a sun deck (sun lounges) or swim platform, can also be used for tender storage while under way. A retractable or removable bimini top could be installed the full length of the cockpit and with the addition of clear plastic sides could turn cockpit into an enclosed weatherproof space at anchor,etc.

 

Lines of C1760

 

Eric Sponberg's FreeStanding Rig Design

Interesting that in the final results of the voting the number 7 entry, that of Eric Sponberg won out over the other top ten finalist.
http://www.cruisingworld.com/polls.jsp?ID=845

Also interesting the small total number of voters considering the readership of that magazine. (294)

Personally I thought this design was the most innovative and complete of all of the top ten. I was surprised that it even lagged behind at first in the voting. But it appears there were some observant readers in the end. Read his website description of this vessel:
http://www.sponbergyachtdesign.com/Globetrotter45.htm

I was surprised at a couple of negative comments by the judges concerning the use of this free-standing rig in the open ocean, particularly considering Eric's vast experience with these free-standing designs, and other vessels that have utilized free-standing rigs. He even provides for a conventional rig alternative.

I think it just speaks to the very conservative nature of the American sailing scene, including the judges in this contest.....too much same old...same old.

 

Other Contestants

It does appear as though we may have a difficult time getting in touch with the other contestants of the contest so that they might present their entry into this discussion...too bad, we might have seen some more interesting revelations

 

Brian, Have you emailed Dave (given that he started the thread..) or Cruising World to see if either can contact the other contestants?
I've emailed one who I know entered...

 

NO Replies...Total Silence

I've emailed him, and a number of the judges, and I sent a reply to Cruising World mag to ask that they notify the other contestants. All to NO Avail...no reply...total silence

 

good initiative, well done Brian and Will, lets hope to see a few more designbriefs here
only now i read this poll and with all respect i have to say for example a free magazine
or postcard covering the contest would have been decent to the rest of us in my book
than again, contestboat shows redone renders on their site without any reply eighter

 

Here is my brief for my submission. I would have liked to take it for a second trip around the design spiral, but I ran out of time. Managing time is just as importanat as anything else---

It would be nice if these kind of contests would occur more often.

 

Hey Doug,
I think you posted the wrong PDF. And you might consider a smaller file size with the correct one so more people can open it with slower connections
Brian

 

Hi Brian,
I posted the T.T. my contest design because it was my favorite part of the entire submission. I thought it would be cool for a couple to be rowing together and looking good on the way to the dinghy dock.

 

Oceansky 57 Cat

In regards to the Oceansky 57 cat, the boat itself was concieved and drawn up 2 and a half years ago. When the competition was announced and with the deadline approaching, I was up to my armpits in a 45 ft alloy power cruiser. With 1 day to the deadline, I decided to do something different. So I dragged out that design and for fun, I entered it. It was good to see that it was voted "Best Cat' and the only multihull to get into the Top 10.
Regards Mark (ARINA)