Proboat Design Comp 2 Results

[Mat-C]

Alik, I notice in the specs for your Silver Arrow that the LCB/LWL is quoted as 0.406.
Is this 40.6% as measure from the bow, or stern?

Oh - and a big BRAVO to you for giving such detailed specs on your website!!

[Doug Lord]

Originally Posted by Alik

OK, one of winning designs is mine

Yes, I also agree that they look similar, but this is obviously result of optimization within very tight restrictions. We played with milthihull option and found that it will not work. We tried number of length - power - weight options and found the length we should stay with. Actually I can post some results of analysis...

As to the 'lack of fresh thinking' - well, we are practicing designers and develop practical designs within requirements. This time maybe we did it better; next time someone else will succeed.

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Congratulations, Alik!

[Doug Lord]

Originally Posted by Willallison

Well done Alik! A thoroughly well-conceived and executed design... just as we would expect.

I know for a fact that there was at least one multihull offered as an entry... and whilst it was not originally conceived with the design comp in mind, it certainly met all the requirements.

No, it was not mine
Indeed mine was a development of an idea that I've been tossing around on these boards for a few years now... and is probably closer to being 'outside the box'. The displacement monomaran, as I have termed it, met all the design constraints and far exceeded the 2 gph consumption constraint.
Having said that, I entered it in the full knowledge that it was unlikely to win - you can make your own assesment based on the attached pics and info....

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Impressive,Will-look forward to seeing the "model".

[Alik]

Originally Posted by Mat-C

Alik, I notice in the specs for your Silver Arrow that the LCB/LWL is quoted as 0.406.
Is this 40.6% as measure from the bow, or stern?

Of course from stern.

[Willallison]

Originally Posted by Alik

Of course from stern.

Mat, like me, you are probably used to seeing it expressed the other way around... from the bow. It think this stems primarily from expressing the LCB (and other centres) as they are related to a typical 10 station boat. So, the LCB at say station 5.5 or 6, would equate to 55 or 60% of the waterline length aft of the bow.

Designers who use ISO standards - as I know Alik does - measure from the stern.

And of course, as this vessel is designed to run well into planing speeds with the largest 140hp option, she'd be an interesting beast if the LCB were located 40% of the LWL aft of the bow!

[Alik]

In standards we use middle is 0.5LWL, also '+' means fwd and '-' means aft. So -10%LWL means 0.5LWL-0.1LWL=0.4LWL. Also consistent with performance predictions methods we use.