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I wonder if there's any connection between a thick film of oil on the sea
making it calm and those using Seagull outboards always experiencing calm
seas?
Jim Nolan P-19 #426 Panache
>From: "Dickerson, Richard" <Richard.Dickerson@TTMC.TTUHSC.EDU>
>To: "'CHARLIE'" <charlies-haus@mindspring.com>, "'Potter List'"
><wwpotter@tscnet.com>
>Subject: RE: Heavy seas - oil?
>Date: Tue, 1 Feb 2000 11:52:25 -0600
>
>Massive quantities of a heavy fuel or bunker oil are required. IF the film
>is too thin, it lacks the strength necessary to prevent spray. The whole
>purpose is to do that. Ships in the second world war would pump out many
>gallons. Wind will move a slick across the water rapidly. Remember, it is
>a layer floating on top of the water and will be moved by current and wind.
>Richard Dickerson, Ph.D., DABT
>Associate Professor, TIEHH and
>Department of Pharmacology
>Texas Tech Medical Campus
>3601 4th Street
>Lubbock Texas 79430
>806 743 2425 xt 232
>806 743 2744 fax
>
> > ----------
> > From: CHARLIE
> > Sent: Tuesday, February 1, 2000 7:09 AM
> > To: Kent Crispin
> > Subject: Re: Heavy seas - oil?
> >
> > 202010808
> >
> > Kent:
> >
> > Please do not take offense - non is intended, at the the
>following
> > questions, they are meant only to enlighten and establish credibility.
> >
> > What empirical experience using 'wave damping oil' have you had?
> >
> > If yes, what type/how much of the "dispersant" was used?
> >
> > What was the "Sea state"(before and after dispersal) and wind
> > conditions?
> >
> > What was the size of the vessel in the action?
> >
> > When/where did the action occur?
> >
> > Another reference; "Heavy Weather Sailing"(1978 Ed.) by A. K. Coles,
>pages
> > 218, 225, 279-281 must be read in full to separate facts from anecdotal
> > items; a concensus of opinion among the Royal National Life-boat
>Institue
> > people is that to be effective oil has to be used in "considerable
> > quantities", and that the average life-boat(35+ feet & up) does not have
> > the capacity to carry needed amounts; further "if anything, a smaller
> > yacht would require more oil than a large one"; and lastly "there seems
> > little evidence to support the text book theory that a thin film of oil
> > seeping from an oil-bag will subdue really big breaking seas.
> >
> > Anecdotal info, on almost any small-boat topic, we have
>a-plenty;
> > we need authoritative, scientifically documented data(data gathered
>under
> > controlled testing or in actual use at sea by competent Heavy Wx
> > sailors/scientists) to help us make 'reasoned judgements' on matters of
> > Seamanship.
> >
> > My experiences in heavy weather have been limited: 1) to North
> > Atlantic crossings on the Queen Marry and various Navy Assault
>transports
> > as a passenger; 2) many intense Squalls w/max of 8ft short, choppy seas,
> > single-handing19', 23', 28' sloops; none of which qualify for the kind
>of
> > heavy wx sailin that is being discussed.
> >
> > Contrary to my normal practice, I have included Ken`s note, since I
> > believe w/o it my questions, et al, lack true intent.
> >
> > 72 y Paz Grover
> >
> > >On Mon, Jan 31, 2000 at 01:13:43PM -0500, CHARLIE wrote:
> > >>2) A 15/19 couldn`t carry enough oil/detergent -whatever, to have
> > >> a salutary effect on a 'Great Sea' anywhere; a barrel of oil weighs
>in
> > the
> > >> vicinity of 400pounds<G> and just can`t see HA`PENNY lcockpit loaded
> > >> w/200pounds of detergent
> > >
> > >The amount of oil needed is very small -- we aren't talking about raw
> > >crude, here, but rather light oils that spread to a layer a few
> > >molecules thick.
> > >
> > >Wave action is caused by interaction between wind and water, and is
>very
> > >sensitive to the surface characteristics of the water. You can see
>this
> > >anywhere there is an oil slick -- a breeze will cause micro-ripples on
> > >any body of water, but under an oil slick it will just be smooth. The
> > >micro-ripples in turn interact with the wind -- the "rougher" surface
> > >gives the wind a better "grip", and improves the energy coupling
>between
> > >wind and water. An oil layer reduces that coupling. An oil slick
> > >spreading a quarter mile behind gives you quarter mile where the
> > >effectiveness of the wind at agitating the water is reduced, the
> > >probability of breaking waves is reduced, etc; and it doesn't take all
> > >that much oil to spread out a couple hundred yards -- you trail a
>gallon
> > >can of oil with a tiny leak on the end of a rope, you don't dump a
> > >barrel of it over the side.
> > >
> > >I don't think this is of any practical value to potters, of course --
> > >if you are out in conditions like that, you will have lots more on your
> > >mind than trailing an oil bag.
> > >
> > >--
> > >Kent Crispin "Do good, and you'll be
> > >kent@songbird.com lonesome." -- Mark Twain
> >
> >
><< attach3 >>
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