Initially we set up as a LeMans-start two lap sprint. The standard
for the piston guys was a three minute countdown to a flying start
for a three lap racing heat. Initially two laps was about the limit
for packs, and we only ran a single heat.
At our second race we ran a single heat on Saturday and Sunday, but
Sunday we recharged for a separate event to put the piston racers in
for a taste of electric power. After that we ran morning and
afternoon heats for complete races on both days, and across the first
season as e-racers began to sort out propellers and racing set-ups
distance per charge grew to a little over 3 miles by season's end.
By three years in, distance was stretched quite a bit, and at a non-
APBA event in Duvall the second heat was run the standard two laps,
but the boats were allowed to continue until packs began to fade.
Most that chose to stay out ran totals of about 5 laps...Dave Cloud's
boat ran something like 8.
In speed trials we towed out to about 400 feet from the trap entrance
to conserve power. The Driver would run through northbound, shut
down, turn around and run back.
Our two great problems were that the weight of lead/acid packs
defeated design principles of the boats and lacked needed density, so
sag cost about 5 mph on the return pass. And motors were limited to
about 5,500 to maybe 6,000 rpm and unable to take advantage of modern
propeller design.
Running a lithium polymer pack Mike Bontoft carried over double the
capacity despite only running something like 132v, with pack weight
pared from 500 pounds down to 80. The lighter weight let the boat fly
airborne on the prop-tips as it was meant to, and the pack's super-
density allowed Mike to start his run directly from the pits and run
the lake end to end like the piston folk. Even better, for the first
time ever an electric boat was making return passes faster than the
initial run. And there was one more pack density benefit...Mike used
some of the surplus to gear prop-speed up to the 8,000/9.000 rpm
range where they're most efficient. At kilo trials, APBA's PRO
Category chair was jumping with delight at the prospect of boats like
Mike's as a racing class that could outrun the fastest stock class
and operate within the APBA clock-start window.
Regarding Zombie's record, it probably should have set last week, but
the post-failure symptoms appear to have been regarded as a data-feed
or controller problem and it took a while to discover that an "un-
plugged" reversing contactor was the culprit. John had left the
contactor unconnected to save time getting to the track and the
controller was having start/stop fits searching for it.
Perhaps the most interesting thing for members here to note in both
records was the huge jump in range these batteries afford. With the
current pack Mike could race competitively with piston boats for full
heats, and the only reason Mike didn't push past 100 was that the
pack's advantages pushed the hydro about 14 mph over the hull's
design speed. At the trap end he was running about 104...The boat was
getting seriously flakey, running right at the edge of impersonating
a bird. The 100 plus record will be there, but in a new, slightly
longer hull with a full safety-cell.
And in Zombie's case the car was driven over 20 miles on city streets
to PIR and run hard through the quarter three times, turning faster
times that it's then current record, before being given a quick top-
off recharge to run for the new 10.4 second record.
I'll admit that costs seem pretty steep, but economics and energy
concerns have held open a luring window long enough to make
manufacturers gamble on change. The gamble has already forced costs
down quite a bit, and stirred development a lot. Currently I'm
looking at a lithium source for a 48v hydro kilo that claims their
cells can be recharged in ten minutes. And for those interested in
lurking possibilities, there's this:
http://web.mit.edu/press/2010/thermopower-waves.html
Finally, for those interested here are links to videos of Zombie's
record and backup runs.
First run: http://www.youtube.com/watch?v=yCx-LYV6KkM
Back-up: http://www.youtube.com/watch?v=7rVTIpS5zb4
John
On Aug 1, 2010, at 8:42 PM, Myles Twete wrote:
>
>
> How many laps do hydroplane racers do? How many e-hydros have hit
> 100mph at this point---I think only one? John P. would know.
> I'm glad John Wayland's Zombie car finally got into the 10-sec
> 1/4mile times---he's dreamed of that for years.
> And while he didn't come close to 10.4 seconds a week ago at his
> NEDRA drag racing invitational, to get there one week later is
> astounding.
> I only wish I were there this weekend instead of last.
> Thanks James.
> -Myles
>
>
> From: electricboats@yahoogroups.com
> [mailto:electricboats@yahoogroups.com] On Behalf OfJames Massey
> Sent: Sunday, August 01, 2010 8:31 PM
> To: electricboats@yahoogroups.com
> Subject: [Electric Boats] high power / low weight batteries -
> Jetboat/dragboat potential
>
>
> G'day All
>
> History has come to the EV world.
>
> White Zombie, a 1970's Datsun car, street legal but used for drag
> racing, has been fitted with Kokam helicopter starting batteries.
> Over the last few weekends the car has seen some adventures,
> including destroying the motor it had, and getting a bigger motor
> installed.
>
> The biggie is the track time results:
> 0 to 60 mph in 1.9 seconds (Bugatti Veyron 0 - 60 mph takes 2.6
> seconds and touted to be the fastest production car to 60 mph,
> elsewhere I found mention of 02 Lingenfelter Chevrolet Corvette as
> THE fastest street legal car with 0-60 mph 1.97 seconds, not any
> more!)
> 0 to 107 miles an hour in less than six and a half seconds (1/8th
> mile time).
> 10.4 second ET in the quarter mile.
>
> Then drove it home without charging. You Tube videos are up.
>
> What does this have to do with boats?
>
> There has been a recurrent theme about jet-boating. Lead-acid + Jet =
> very short range.
> Typical Thunder-Sky (Sky energy, etc) Lithiums = better range,
> limited power.
> A123 lithium = better range and power, pain to set up (small cells).
> Kokam batteries = more power than you can use and better range again.
>
> Still short range, but potentially better performance than an
> equivalent V8 (etc).
>
> BUT (big BUT) very new, very, very, new. Price reflects the very
> newness. White Zombie is sponsored, but if you were to buy an
> equivalent to their pack, expect a $100,000 price range.
>
> If your pockets are deep enough, electric can embarrass petrol for
> short duration.
>
> Now back to your normal discussions...
>
> Regards
>
> [Technik] James
>
>
>
>
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