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Old August 6th 07, 07:10 PM posted to rec.aviation.piloting,rec.aviation.homebuilt,rec.aviation.ultralight,rec.aviation.soaring
Ken Finney
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Posts: 190
Default Electrically Powered Ultralight Aircraft


"Bill Daniels" bildan@comcast-dot-net wrote in message
. ..

wrote in message
ups.com...

For a battery-powered car todays practical approach is to have a
second engine for backup or as you suggest to generate electricity.
When they start selling cars only powered by batteries I'm going to
invest in a tow truck business. For aircraft the best use for
batteries today is to start the engine. Lange has demonstrated what is
possible with today's batteries/motors and while it provides an
attractive self-launch the cost and range tradeoffs bring it back into
perspective.



I think this is a little pessimistic. Critics of the pure electric seem
to focus on the "one-car does everything" strategy where it's easier to
find faults. The "electrics don't equal engine powered cars" isn't the
whole story.

Americans, at least, seem to have developed a another strategy for dealing
with fuel prices that spike every summer. They own an old, cheap econobox
they dust off when gas prices exceed $3. They drive their SUV's only when
they need the capacity.

This 2-car strategy works for pure electrics (EV's) too. Survey after
survey notes that a huge majority of drivers do less than 40 miles a day
which is easilly met with EV's. The current best range of 100 miles
provides better than a 2:1 safety margin.

Economically, the 2- car strategy can be implemented without owning two
cars. Just RENT the SUV when you need it. Considering total ownership
costs, this is a good deal. Looking at all the rental discounts available
to me, I don't plan to replace my SUV.

Interestingly, range alone isn't, in itself, a killer. If the battery
pack can be recharged in less than 10 minutes, the limited range is less
of a factor. The newest Lithium Phospate cells can reach 80% charge in
one minute and full charge in 5 minutes. So, if you invest in a tow
truck, get one with a diesel generator set.

Most likely, popular parking areas will be equipped with charging outlets.
I can imagine shopping centers with signs saying, "Shop here while you
recharge, FREE!" I can also imagine employers getting tax incentives to
provide their workers with access to a recharging station.

My bets are on the pure electric vehicle.


In the early 1980's, Mother Earth News made a hybrid car that got 75 miles
per gallon. It was a Opel GT (heavy) powered by a jet engine starter motor
(inefficient) and a relatively inefficient small gas motor. The gas motor
powered the alternator which charged the batteries which ran the electric
motor. At the time, they noted that this wasn't new technology, but was the
way diesel train engines worked. In 2010, GM will introduce the Chevy Volt,
which is pretty much the same concept, which I'm convinced is the way to go.
I think this does have promise for airplanes as well. The IC engine and
batteries can be place for optimum weight distribution, and the IC engine
can be heavilly vibration isolated.