OK....This is obviously getting out of hand, so I maybe I should
offer a sorting-out.
This began with a "whaddayathink" post about a propane-fed outboard.
I had an opinion, but didn't think it was important, and thought the
thread was too distant from the group's mission to last. It managed
to survive though, so I tossed in my nickel to say that I thought
means might be at hand to accomplish the propane motor's potential
with batteries.
As a model, I chose a marathon racer from an event run 20 years
ago...Long, slick, wakeless, meant to run good speed over a long
distance. The point I was trying unsuccessfully to make was that
current tech might not pull a dinghy's performance up to the full
standard of the marathon racer, but it should bring performance up to
or beyond that of a 25cc weedeater outboard.
Perhaps this example might have been better:
The current fastest speed for electric is 98.8 mph, besting the 70.5
that was the standard for over a dozen years. The 70.5 mph mark was
set with a 500 pound lead-acid pack that demanded a shortened run-
time to complete the required 2-way passes of a 1 kilometer course,
always lost about 5 mph on the return pass from battery sag and
limited propeller rpm to a speed about 2000 rpm short of optimum.
Mike Bontoft's record was set with an 80 pound Lithium pack that, for
the first time ever, managed return passes faster than the initial
pass (98.3 down/99.3 return) could run the full course 5 or more
times on a charge, and had the additional surplus density to drive
gearset that put propeller rpm at its best.
A 21 cell (22v) pack of the Li-Pol batteries Mike used would roughly
equal the weight of a single car battery and should produce all the
power needed for regular use and plenty of distance...If I was
interested in something more exotic I'd be looking into one of
Cyclone Technology's steamers.
John
On Feb 21, 2012, at 2:39 PM, KEN wrote:
>
>
> guess ya missed the pic Eric.. was a 24ft maybe 30" wide fast
> electric kayak.
> it covered 72 miles in 6 hours
>
> --- On Tue, 2/21/12, Eric <ewdysar@yahoo.com> wrote:
>
> From: Eric <ewdysar@yahoo.com>
> Subject: [Electric Boats] Re: Propane outboard engine
> To: electricboats@yahoogroups.com
> Date: Tuesday, February 21, 2012, 4:11 PM
>
> Hi Kirk,
>
> "needle boat"? The only reference that I found to the term online
> is a Lego model of a small attack boat. I don't think that is what
> you are referring to....
>
> There are pickle fork boats, sometimes shortened to pickle boat...
>
> Fair winds,
> Eric
> Marina del Rey, CA
>
> --- In electricboats@yahoogroups.com, John Paramore <watertoyz@...>
> wrote:
> >
> > Ummmmmm...What?
> >
> > On Feb 20, 2012, at 8:57 PM, Kirk McLoren wrote:
> >
> > > needle boat - very low drag
> > >
> > >
> > > Nemo dat quod non habet
> > >
>
>
>
>
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