Low Length/Displacement Hulls

Hello Adler,

Well, one thing, Okeanis would never fit under the bridges on the River Thames, but that is the only negative I can see.

I picture myself mooring up at the Ferry in Cookham this summer and so, the beam can only be 14 feet.

http://www.theferry.co.uk/

With a cruising speed of 15 knots with only 2200 installed hp, the Okeanis is a great design. Her waterline length looks close to her overall length, so the L/B ratio is about 5.6 to 1? I'm just guessing here, but from looking at images of the water passing the hull, were Okeanis 43 metres length overall, she might make perhaps another 3 knots with the same engines. The raised foredeck with that sweeping sheerline; she makes the hair on the the back of my head stand up Heaved to, Okeanis would look like she was racing away. Thank you for posting the link.

Regards,

P.

 

Alik,

An intriguing design of bow. Ram shaped wave piercer, with very high mounted chines (would that be the right term?) to provide buoyancy and deflect water, as necessary in plunging seas. Almost, Carolina flare concept, to prevent green seas over the prow. It should cut through waves like a tailor's shears through silk fabric. Thank you for presenting it to the forum.

Nautilus, a curious fictional submarine from the film "The League of Extraordinary Gentlemen", would work very well as a wave piercer, because any swells that reached the bridge would be so large as to require the vessel to submerge. Maybe that's the way to go? Surface when the sun appears.

http://www.hlj.com/product/WAVTL-02

Regards,

P.

 

We call this shape 'can opener bow'. Advantages - reduced wetness, better arrangement of anchor and mooring gear.

 

Alik,

No Joke. That was what I thought I should have included in my last post, only we Brits call it a tin opener and I did not want to be misunderstood,

 

This means one day we can start designing kitchen utensils

 

Wok do you mean?

Take a look at these culinary delights.

http://www.peterfreebody.com/downloads/Yachting_Classic_Issue27_2005.pdf

Regards,

Perry

 

Dear ΠΕΡΙΚΛΗΣ,

Thank you for your notes.
I worked on speed issue and last summer the matter was solved.
Of course we didn't increased the length.
We design and built new propellers.
See please the attached file.

New Speed Performance Data:
Mean Cruising Speed: 16.7 knots
Mean Max.Speed: 18.6 Knots.
Effective Horse Power: not changed. (2200CV).
Reduction ratio: not changed.
The measuring speed method was through GPS.
When was measured on mile post std - the results were:
Mean Cruising Speed: 17.1 Knots
Mean Max.Speed: 19.0 Knots.

 

Ah, the old propeller trick. I might have know you'd be devious. Well done.

Best wishes,

ΠΕΡΙΚΛΗΣ,

Addendum

How many blades on the previous propellers please?

 

Dear,

Previous propellers 5-blades Dia:1200mm
Installed propellers 6-blades Dia:1295mm

The important point is that: The commissioning sea trials were applied under light ship condition.
The last sea trials were applied in heavy ship condition at 81% of Full Load (Fuel+Water+Waste).
Please see the attached file.

Thank you,

ΜΕΓΑ ΤΟ ΤΗΣ ΘΑΛΑΣΣΗΣ ΚΡΑΤΟΣ

 

Adler,

I can only translate using Babelfish, so in answer to ΜΕΓΑ ΤΟ ΤΗΣ ΘΑΛΑΣΣΗΣ ΚΡΑΤΟΣ I wish you ήρεμες θάλασσες

Thank you for the Sea Trials evaluation and the information about the propellers.

Kind regards,

Perry (My given name)


Addendum.

Adler, I think I'm a dunce. I did not scroll down on the first link you sent me. Now I have done, I can see those propellers in Technicolor. Thanks.

 

I read the article on efficient powerboats in the Masthead but am not sure why it was written. Seemed a long way round to draw some pretty obvious conclusions.

Mik Storer's Solar boat does use the same basic canoe hull shape but I'm not sure it goes fast enough to reap any benefits from it.

 

Dear Perry,
the translation by word is:

ΜΕΓΑ = GREAT

ΤΟ = THE

ΤΗΣ ΘΑΛΑΣΣΗΣ = SEA'S

ΚΡΑΤΟΣ = STATE =[ The Authority that Controls and Keeps the Law , the Treasure and the Power of Democracy;The humans' freedom.]

GREAT THE SEA'S STATE = had the meaning "A State is Great if is based on Sea's Control and keeps the Sea ways open and free".

It was the main phrase from Perikles' Speech to the Parliament of Ancient State of Athens regarding to convince them voted the extra balance which spended to enlarge and extend the number and size of Navy Ships for an effective State's defence that affected to the Social Progress.

Actually Pericles when expressed his idea had established the base and the corners of marine field.

At your disposal

 

G'day Albert... Wild looking beast - that evil looking bow is somewhat reminiscent of the VSV Mary Slim http://www.multimarine.co.uk/VSV.html

Truth be known, I ran out of time to fully refine some of the styling elements of Sliver - like the slightly odd-looking windscreen. I think the idea has merit, though other variants - like Tom's glider and my own version of the same concept - are likely to have wider appeal.

Re the Masthead article, I haven't read it yet, but I think much of the "debate" over SL vs Fnv derives from locality as much as anything else. SL seems more commonly used in the US, Fnv in european countries.
Perhaps, once they come to understand the elegance of the metric system, Americans will also start using Fnv...

 

Not just that. Before inventing formulas one should fully understand the subject...

 

Well... I was rather surprised to see that the image Perry posted was from way back in 2001!

Albert...
Why not a letter to the editor of the Masthead (Norm Nudelman)... perhaps you could elicit a reply as to why Dave uses the DLR / SL as opposed to Fnv...