
Environment-Friendly Inexpensive Electric Airplane - kirubakaran
http://www.dancewithshadows.com/aviation/electraflyer-c-electric-mini-plane-makes-flying-cheaper-than-driving/
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DabAsteroid
Judging by the information on the Electraflyer website, much of the
information at the blog seems to be wrong. The $18,385.00 price is not for the
pictured Electraflyer C explerimental plane, but for this open-air frame
tricycle with fabric wing:

<http://www.electraflyer.com/tech.html>

It is that tricycle that weighs only 247 lbs, not the experimental plane (the
Electraflyer C), which is based on an "all metal Moni motor glider".

<http://www.electraflyer.com/electraflyerc.html>

 _The Moni was first introduced at the 1981 Oshkosh Convention. It was
designed by John Monnett and sold as a complete kit including the engine and
instruments. ... Approximately 380 kits were sold between 1982 and 1986. It is
unknown how many Moni's have been completed and are currently flying.

The manufacturer of this neat little airplane, Monnett Experimental Aircraft,
later INAV Inc., went out of business in 1986._

<http://edhlund.com/monimain.htm>

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DabAsteroid
_A direct drive 5 KWh (sic) electric motor ... flight time would be 1.5 to 2
hours. ... A full charge will cost you around 60 cents depending on where your
power comes from._

If the energy were from wind or solar, the energy would cost around $1/kWh *
5kW * 2hrs = $1/kWh * 10kWh = $10. If that can last 140 miles, that works out
to 7 cents per mile, or $5 per flight-hour.

 _The top end battery pack costs 8,500 $. So that is 1000 cycles = 1500 flying
hours at a cost of 6.2 $ per hour! (cost of battery replacement divided by
flying hours plus 60 cents per charging cycle)._

If flight time were 2 hours, the pack replacement cost would be
$4.25/flighthour. With solar/wind electricity as $5/hr fuel, this would add up
to $9.25/flighthour.

Edit: the website says the large battery pack only holds 5.6kwh. Perhaps with
losses (charging, etc.), that would approach the above figure of 10kWh per
flight.

<http://www.electraflyer.com/prices.html>

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DabAsteroid
Here is a flight report from a Moni motorglider, similar to the one
erroneously pictured at dancewithshadows.com:

<http://edhlund.com/PIREP01.htm>

 _On my seventh flight I was ready for some mild aerobatics. I entered a left
barrel roll at 4000 ft. and, 3/4 complete, experienced airframe vibration,
loss of elevator control and nose pitchdown. I closed the throttle and held
full back elevator but the pitch attitude, airspeed and vibration level all
continued to increase until I was at a nearly 90 degree nosedown attitude and
the airframe sounded like I was inside a garbage can being assaulted by
baseball bats. About this time there was a tremendous "crack" and the airplane
dissapeared from around me. I was tumbling through the air losing
conciousness, but still strapped in my seat. Because of the violent motion I
was unable to release the lap belt. The last thing I remember before losing
conciousness was reaching for my parachute D-ring while saying goodbye to the
world.

Miraculously, I regained conciousness on the ground, where I slowly realized
that I was still strapped to the rear of the airframe, which had joined me in
a fully unconcious parachute descent to a sitting landing in a nice plowed
field. Another complete story follows where I got the seat belt released, only
to be parachute dragged in a 20 knot wind with one arm and a dislocated
shoulder entangled in the shroud lines, before finally shedding the chute.
There were lots of broken bones and aches and pains. The NTSB investigation
revealed that the starboard wing skin had debonded. The skin had departed
outward, broken the spar and broken the aircraft in half at the spar box.

After some healing, and doing some research, I found that experts had been
advising Monnett against this bonding method. He subsequently mandated a
riveted wing, but didn't describe why as eloquently as I could have. Your
editor, Carlos Emmons, and I then stripped the bonded skin from his wings (he
wasn't flying yet) so easily it couldn't be believed. A little loosening with
a knife at the trailing edge to get a finger hold, and a single jerk had the
whole skin in our hands! We had bonded both aircraft and followed the book.
...

You do not have a certificated aircraft. The designer probably had no
engineering skills, expertise or resources._

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DabAsteroid
These are the Moni motorglider specs:

<http://edhlund.com/monispec.htm>

It weighed 260 lbs, empty. Construction: "all aluminum bonded and riveted".

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DabAsteroid
_Environment-friendly ... solar or wind energy_

In what way(s) could diffuse fuels such as solar and wind be considered
environment-friendly?

~~~
jcdreads
Here's the most obvious way: they cause essentially zero pollution compared
with energy from fossil fuels. What wind- and sun-related environmental peril
did you have in mind?

