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Electrically Powered Ultralight Aircraft



 
 
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  #1  
Old August 5th 07, 05:52 PM posted to rec.aviation.piloting,rec.aviation.homebuilt,rec.aviation.ultralight,rec.aviation.soaring
Larry Dighera
external usenet poster
 
Posts: 3,953
Default Electrically Powered Ultralight Aircraft



Electrically Powered Ultralight Aircraft

Below is a report of an electrically powered ultralight aircraft.
Further down is information about Sonex's electrically powered
home-built aircraft, and below that is information about Royal
Aeronautical Society's 2007-8 design competition (submissions close
May 2, 2008).

Personally, I'd like to see an electrically powered parachute
(http://skyhighflying.com/homepage.html) design attempted. Surly the
lighter weight would require less power. It would seem that
lithium-ion polymer batteries are a potential enabling technology.


AVGAS? WHO NEEDS IT? TRIKE RUNS ON BATTERIES
(http://www.avweb.com/eletter/archive...ll.html#195816)
While concerns over price, availability and environmental impact
have aviators worried about the future of fuel, one ultralight
flyer in New Jersey has already solved that problem. Randall
Fishman has been testing lithium-ion polymer battery packs to
drive the prop on his ultralight trike, and he says they work
great. They are powerful, smooth, sturdy, safe and quiet, Fishman
claims. "The closest thing to a magic carpet ride ever," he says
on his Web site (http://www.electraflyer.com/). The quiet is not
only enjoyable for the pilot, it improves relations with
neighbors, he notes. The batteries will run for up to two hours
and cost about 60 cents to charge via a standard electric outlet.
However, the batteries are expensive -- $3,800 to $7,500,
depending on size.
http://www.avweb.com/eletter/archive...ll.html#195816

First attempted takeoff video:
http://www.youtube.com/watch?v=Wksx-jmhY7c


Brochu
http://www.electraflyer.com/brochure.pdf
Technical Specifications:
Motor - 18 H.P. High Torque - 90% Efficient at Cruise
Controller - Electronic, Pulse Width Modulation, For High
Efficiency and Smooth Control
Battery Packs - Custom Built, Lithium Ion Polymer, Super High
Capacity Choose the Size You Want
Voltmeter - To Monitor How Much Power Is Available
Ammeter - To Monitor How Much Power You Are Using
Thrust - With Folding Prop - 140 Pounds
With Big, Ultra Quiet Prop - 155 Pounds
Duration - Up to Two Hours Depending on Battery Pack Chosen, Total
Weight and Efficiency of the Wing - 1 to 1.5 Hour Flights Most
Common
Total Weight - 210 to 250 Pounds Complete With Wing and Battery
Packs The ElectraFlyer is a True Legal Part 103 Ultralight

Electric Aircraft Corporation
Randall Fishman, President
phone: 561-351-1190
website: www.ElectraFlyer.com
email:


http://www.electraflyer.com/52_53_womf.pdf
An EAA MEMbEr First...
The ElectraFlyer, an Electric-Powered Trike!


http://www.electraflyer.com/lightsport.pdf
Light Sport and Ultralight Flying July 2007






================================================== =
Sonex web site: http://www.sonexaircraft.com/

Photo of Sonex e-flight electric aircraft:
http://www.sonexaircraft.com/news/im...flight_058.jpg

Photo of electric powerplant:
http://www.sonexaircraft.com/news/im...light_5947.jpg

Diagram of e-Flight powerplant:
http://bioage.typepad.com/.shared/im.../25/sonex1.png

Pricing: http://www.sonexaircraft.com/kits/pricing.html


Article:
http://www.greencarcongress.com/2007...aft-.html#more

http://www.sonexaircraft.com/press/r...pr_072407.html
Sonex Aircraft, LLC and AeroConversions Unveil E-Flight Initiative for
Sport Aircraft Alternative Energy Research & Development

Electric Power; a new mission: The contemporary E-Flight electric
project will benefit greatly by the maturation of technology since our
initial studies. Using a purpose-built AeroConversions brushless DC
cobalt motor, controller, and highly efficient battery and charging
system, the E-Flight electric systems will be able to power a larger
aircraft to higher top speeds with greatly increased endurance.
E-Flight’s proof-of-concept prototype will use the flight proven Waiex
airframe, flown single pilot only, so that the emphasis can be placed
solely on powerplant research and development. Initial top speeds will
reach approximately 130 mph, and endurance is expected to range
between 25-45 minutes or longer, depending upon power usage on each
individual flight.

The initial emphasis for the E-Flight proof-of concept aircraft has
been shifted away from immediate pursuit of FAI speed records,
although the possibility remains that those records could be obtained
in short-order after successful first flight. With the advanced state
of the technologies concerned, the goal of the project is to develop
and prove the application of the technology and pave the way for
near-term electric powerplant Sonex and AeroConversions products for
sale to the sport aviation marketplace and beyond.

The current state and growing popularity of electric powered model RC
aircraft leads the layman to assume that an electric powered aircraft
of this type is simply a matter of hooking a bigger battery to a
bigger motor, charging it up in an hour or two and taking-off. While
that is essentially true in raw principle, the reality of this project
is that scaling-up these technologies in a viable manner presents
significant challenges.

• Electric Power; AeroConversions Electric Motor: Brushless DC cobalt
motor technology has advanced significantly since 1994’s Flash Flight
study, allowing the design team to now consider their use, however,
just like before, a suitable brushless DC cobalt motor of this level
of power output with an acceptable size and weight does not exist and
can not be built and provided by a third party vendor without
incurring unacceptable costs. As a result, the design team, in
collaboration with Bob Boucher of Astro Flight, Inc., has designed and
built a completely new AeroConversions motor.

This motor is the most powerful, lightest-weight, and efficient unit
of this type ever produced. It is a 3 phase, 270 volt, 200 amp motor
that will be over 90 percent efficient. It uses elegantly designed CNC
machined anodized aluminum and nickel-plated steel parts in
combination with “off the shelf” bearings, races, snap rings, magnets,
etc.

The prototype AeroConversions motor is slightly larger than a 35 ounce
coffee can and weighs approximately 50 pounds. The motor is a
modular, scalable unit. The motor core’s design has modular sections
that can be reduced to a lower-output, smaller motor (shortened in
length), or added upon to make a larger motor with a higher power
output.

• Electric Power; AeroConversions Electronic Motor Controller:
Electronic motor controllers for brushless electric motors are quite
commonplace today, mostly used in the electric RC market. A suitable
controller for a 270 volt, 200 amp motor does not exist. Running such
high current requires much larger components. Although there are a
handful of third party vendors who could design and build the
appropriate controller for this project, it would take 6-7 months lead
time and cost 20-50 Thousand Dollars. The time and cost associated
with acquiring such a controller was deemed unacceptable and the
research and development team, in cooperation with a key electronics
expert, began designing a proprietary AeroConversions electronic motor
controller.

The controller can commutate the motor in two different ways: using
Hall effect sensors to determine the magnet core’s position in
relation to the coils, or using the motor’s back-EMF to sense rotor
position, eliminating the need for Hall sensors. The AeroConversions
controller will initially employ a Hall effect sensor-equipped motor,
but back-EMF controlling will also be explored to potentially further
simplify the AeroConversions motor design. The AeroConversions
controller will also provide in-cockpit monitoring of battery power
levels to the pilot.

• Electric Power; AeroConversions Battery System: Most contemporary
electric powerplants for gas-electric and pure electric cars and
previous generations of RC electric vehicles utilize Lithium Ion
battery technology. While much improved in power density and discharge
rate over lead-acid and NiCad batteries, Li-Ion batteries still do not
offer enough power discharge-to-weight ratio to support an electric
powerplant for an aircraft that is based on battery power alone and
has a market-viable endurance. Newer RC electric vehicles, cell phone,
laptop computers and other mobile devices have been moving toward
Lithium Polymer cells. Li-Poly battery cells can safely discharge at a
rate of 25 times their capacity, or “25c.”

With all the extra energy of a Li-Poly cell, however, comes extra
volatility. The E-Flight design team has engineered and constructed 10
battery “safe boxes” intended to contain 8 Li-Poly battery packs per
box and consolidate their charge/discharge and balancing wiring into
two sets of multi-pin connectors. The Boxes will accommodate natural
cell expansion and contraction while safely securing each cell pack
and facilitating cell cooling with “cooling foam” padding. Cooling
will further be aided by heat sink surfaces on each box that will have
cooling inlet air directed over them. Additionally, the boxes are
designed to contain and safely direct fire or explosion within the box
through a “blow hole” in the box that will be connected to a small
exhaust manifold.

For the proof-of-concept aircraft, the battery boxes will be removed
from the aircraft and charged individually. The charging units need to
be configured to safely keep all cells balanced during charging.
Lessons learned from the proof-of-concept systems will lead to the
design of more advanced charging and balancing systems allowing safer
battery handling by consumers, including a single-plug charging system
that may remain in the aircraft at all times, featuring easy exchange
of battery boxes to enable consecutive back-to-back flights in a short
period of time by pilots who wish to invest in spare batteries.

Future generations of safer, more powerful Li-Poly batteries show the
near-term possibility of further extended flight duration while
personal electronics and transportation will undoubtedly continue to
push improvement of the technology in years to come.

“By developing a viable electric motor and controller system for this
proof-of-concept aircraft, we will open a door to future flight that
we have only been able to dream of,” comments Monnett. “Self-launching
electric powered gliders already exist. The potential of electric
power goes beyond that single use and relates directly to sport
flying, aerobatics and high altitude flight in purpose-built
airframes. It is essential that our proof-of-concept vehicle is a
conventional aircraft that the majority of aviation enthusiasts can
relate to.”

One remarkable reality about the E-Flight electric aircraft project is
that, by necessity, the entire R&D project for the proof-of-concept
stage of the project will cost less than the price of the average
ready-to-fly LSA aircraft available today. This project undeniably
highlights the spirit of EAA in that it is truly a grass-roots effort
to push technology for advancement of our sport and improvement of our
planet’s ecosystem and it has been accomplished, not by a large
aerospace firm or government agency, but by EAA members on an
extraordinarily cost-effective budget.


http://www.aeroconversions.com/

--------------------------------------------------------------------------------
The official daily newspaper of EAA AirVenture Oshkosh

Volume 8, Number 4 July 25, 2007

--------------------------------------------------------------------------------

Sonex rolls out electric plane
By Randy Dufault

Jeremy Monnett shows off the electric motor and mount employed in a
proof-of-concept Waiex airframe to demonstrate the potential of
compact electric power and advanced-technology batteries. Photo by
Dave Higdon

With the price of oil rising faster than an F-15 in an unrestricted
climb and the potential for $6 per gallon self-serve avgas a real
possibility, alternate ways of powering aircraft, ways that require
much less fossil fuel, are going to be important to the future of
sport aviation.

On Tuesday, Sonex Aircraft LLC took the wraps off its previously
secret e-Flight initiative.

"This is an exciting announcement and one that you are really going to
appreciate," EAA President Tom Poberezny said at the beginning of the
press conference. He added, "It addresses the grass-roots research
that is important to the integrity of EAA and the homebuilt movement.
More importantly, it is growing aviation by making it more
economical."

The most visible aspect of e-Flight right now is a Sonex Waiex
airframe equipped with a proof-of-concept prototype electric
powerplant. The aircraft, which is expected to fly later this year,
will be used to further develop the motor, along with the requisite
control systems, charging systems, and of course, battery systems.

"It was [apparent] that once we started down this path to developing
an alternative power source for the airplane, that we had to do it in
very specific steps," John Monnett, Sonex founder and president, said
when he introduced the electric plane. "The whole object of [the
proof-of-concept] is to come up with a powerplant that is equivalent
in weight and in power to our AeroVee-powered Sonex and Waiex
[models]."

Monnett went on to add the sole mission of the airplane displayed here
is to develop the technologies that will ultimately result in
production systems. The test-bed airplane is also expected to test
other, as yet unspecified, electric power sources.

The prototype powerplant uses brushless, cobalt motor technology and,
according to AeroConversions, is the most powerful, lightest weight,
and efficient motor of the type ever produced. It was developed with
the help of Bob Boucher of Astro Flight Inc. Astro Flight is a major
producer of electric radio-controlled model motors.

The 200-amp motor is 90 percent efficient and operates on 270 volts of
direct current electricity, as advertised by the Waiex’s tail number,
N270DC.

According to Pete Buck, Sonex’s chief engineer, the motor was
manufactured in-house. He added that Sonex expects to construct
virtually all of the components of the future production systems
themselves. Production systems, unlike the current AeroVee engine,
likely will not be offered as kits, due to the critical tolerances and
potential dangers with some of the electrical components.

Monnett pointed out that a couple of technologies are key to making
electric flight a reality. Of course, powerful and light batteries are
a must, but a motor controller capable of managing the high power
involved also is required. A charging system, capable of replenishing
the batteries in a reasonable amount of time, is another must. Sonex
is developing both technologies.

Target flight duration for the proof-of-concept airplane is 25 minutes
to 45 minutes. Production systems are expected to allow for one-hour
flights. Buck says an hour’s endurance is difficult right now but
ultimately is very possible as both the system and the available
technologies are further developed.

In addition to the electric Waiex, Sonex’s e-Flight initiative also
involves two other aspects: the practical use of ethanol fuels in the
AeroConversions AeroVee 2.0 engine and developing other enhancements
to the AeroVee, improving its already-impressive efficiency.

Sonex partnered with Wisconsin-based Renew Fuel Stations, a
distributor of E85, a blend of up to 85 percent ethanol and 15 percent
gasoline, to develop an AeroVee engine configuration that can use the
fuel. Renew’s interest in the project is expansion of the market for
ethanol fuels. Testing is under way right now.

The idea of electric flight is not new to Sonex. It dates back to 1994
when Monnett and Buck looked into the possibility of building an
electric plane specifically for the purpose of establishing speed
records for a new class of aircraft. Although the project was deemed
to be practical, Sonex put the project aside to further develop its
current set of kit airplanes and to support their customers. The
company is committed to completing the effort this time, though
Monnett stated firmly that the e-Flight program will never detract
from Sonex’s commitment to its customers.

Sonex is financing the entire effort itself.

Once production systems are available, Sonex plans to make them
available to the experimental market for installation on other
airframes.

Sonex will present a forum on the e-Flight project Wednesday at 11:00
a.m. in Forum Building 11. More information about the project is
available on the web at www.AeroConversions.com/E-Flight.


================================================== ========



The RAeS General Aviation Group aims to encourage the development of
light aviation through the promotion of technologies, in particular
those that minimise its impact upon the environment.

The 2007-8 design competition therefore offers awards for technical
developments that can include:

• whole aircraft design
• propulsion
• operational methods
• specific technologies within the aircraft.

The competition is open to any individual or group; entries are
particularly encouraged from teams from educational institutions or
RAeS corporate members.

Entries should be received by Friday 2 May 2008 and consist firstly
of a 10 page report , showing how it works, its benefits both to
light aviation and to the environment, and who is responsible for the
entry.

A shortlist of entrants will then be selected, who will be invited to
give a 20 minute presentation at a special event at RAeS Headquarters
in London during mid June 2008. At that event, a judging panel will
select the final winning entries; prizes and final award categories
will be announced nearer to the entry deadline.

Judging criteria will be based upon feasibility, originality,
reduction of impact upon the environment and the potential benefits
to light aviation overall. Final presentations will also be judged
on presentation quality and response to questioning.

The judging panel will consist of highly qualified light aviation
professionals – including representatives from industry, regulatory
authorities and academia.

Further Details:
General Aviation Group
Royal Aeronautical Society
No.4 Hamilton Place
London, W1J 7BQ, UK


  #2  
Old August 5th 07, 06:53 PM posted to rec.aviation.piloting,rec.aviation.homebuilt,rec.aviation.ultralight,rec.aviation.soaring
Phil
external usenet poster
 
Posts: 110
Default Electrically Powered Ultralight Aircraft

On Aug 5, 11:52 am, Larry Dighera wrote:
Electrically Powered Ultralight Aircraft

Below is a report of an electrically powered ultralight aircraft.
Further down is information about Sonex's electrically powered
home-built aircraft, and below that is information about Royal
Aeronautical Society's 2007-8 design competition (submissions close
May 2, 2008).

Personally, I'd like to see an electrically powered parachute
(http://skyhighflying.com/homepage.html) design attempted. Surly the
lighter weight would require less power. It would seem that
lithium-ion polymer batteries are a potential enabling technology.

AVGAS? WHO NEEDS IT? TRIKE RUNS ON BATTERIES
(http://www.avweb.com/eletter/archive...ll.html#195816)
While concerns over price, availability and environmental impact
have aviators worried about the future of fuel, one ultralight
flyer in New Jersey has already solved that problem. Randall
Fishman has been testing lithium-ion polymer battery packs to
drive the prop on his ultralight trike, and he says they work
great. They are powerful, smooth, sturdy, safe and quiet, Fishman
claims. "The closest thing to a magic carpet ride ever," he says
on his Web site (http://www.electraflyer.com/). The quiet is not
only enjoyable for the pilot, it improves relations with
neighbors, he notes. The batteries will run for up to two hours
and cost about 60 cents to charge via a standard electric outlet.
However, the batteries are expensive -- $3,800 to $7,500,
depending on size.
http://www.avweb.com/eletter/archive...ll.html#195816

First attempted takeoff video:http://www.youtube.com/watch?v=Wksx-jmhY7c

Brochu
http://www.electraflyer.com/brochure.pdf
Technical Specifications:
Motor - 18 H.P. High Torque - 90% Efficient at Cruise
Controller - Electronic, Pulse Width Modulation, For High
Efficiency and Smooth Control
Battery Packs - Custom Built, Lithium Ion Polymer, Super High
Capacity Choose the Size You Want
Voltmeter - To Monitor How Much Power Is Available
Ammeter - To Monitor How Much Power You Are Using
Thrust - With Folding Prop - 140 Pounds
With Big, Ultra Quiet Prop - 155 Pounds
Duration - Up to Two Hours Depending on Battery Pack Chosen, Total
Weight and Efficiency of the Wing - 1 to 1.5 Hour Flights Most
Common
Total Weight - 210 to 250 Pounds Complete With Wing and Battery
Packs The ElectraFlyer is a True Legal Part 103 Ultralight

Electric Aircraft Corporation
Randall Fishman, President
phone: 561-351-1190
website:www.ElectraFlyer.com
email:

http://www.electraflyer.com/52_53_womf.pdf
An EAA MEMbEr First...
The ElectraFlyer, an Electric-Powered Trike!

http://www.electraflyer.com/lightsport.pdf
Light Sport and Ultralight Flying July 2007

================================================== =
Sonex web site:http://www.sonexaircraft.com/

Photo of Sonex e-flight electric aircraft:http://www.sonexaircraft.com/news/im...flight_058.jpg

Photo of electric powerplant:http://www.sonexaircraft.com/news/im...light_5947.jpg

Diagram of e-Flight powerplant:http://bioage.typepad.com/.shared/im...categorized/20...

Pricing:http://www.sonexaircraft.com/kits/pricing.html

Article:http://www.greencarcongress.com/2007...aft-.html#more

http://www.sonexaircraft.com/press/r...pr_072407.html
Sonex Aircraft, LLC and AeroConversions Unveil E-Flight Initiative for
Sport Aircraft Alternative Energy Research & Development

Electric Power; a new mission: The contemporary E-Flight electric
project will benefit greatly by the maturation of technology since our
initial studies. Using a purpose-built AeroConversions brushless DC
cobalt motor, controller, and highly efficient battery and charging
system, the E-Flight electric systems will be able to power a larger
aircraft to higher top speeds with greatly increased endurance.
E-Flight's proof-of-concept prototype will use the flight proven Waiex
airframe, flown single pilot only, so that the emphasis can be placed
solely on powerplant research and development. Initial top speeds will
reach approximately 130 mph, and endurance is expected to range
between 25-45 minutes or longer, depending upon power usage on each
individual flight.

The initial emphasis for the E-Flight proof-of concept aircraft has
been shifted away from immediate pursuit of FAI speed records,
although the possibility remains that those records could be obtained
in short-order after successful first flight. With the advanced state
of the technologies concerned, the goal of the project is to develop
and prove the application of the technology and pave the way for
near-term electric powerplant Sonex and AeroConversions products for
sale to the sport aviation marketplace and beyond.

The current state and growing popularity of electric powered model RC
aircraft leads the layman to assume that an electric powered aircraft
of this type is simply a matter of hooking a bigger battery to a
bigger motor, charging it up in an hour or two and taking-off. While
that is essentially true in raw principle, the reality of this project
is that scaling-up these technologies in a viable manner presents
significant challenges.

· Electric Power; AeroConversions Electric Motor: Brushless DC cobalt
motor technology has advanced significantly since 1994's Flash Flight
study, allowing the design team to now consider their use, however,
just like before, a suitable brushless DC cobalt motor of this level
of power output with an acceptable size and weight does not exist and
can not be built and provided by a third party vendor without
incurring unacceptable costs. As a result, the design team, in
collaboration with Bob Boucher of Astro Flight, Inc., has designed and
built a completely new AeroConversions motor.

This motor is the most powerful, lightest-weight, and efficient unit
of this type ever produced. It is a 3 phase, 270 volt, 200 amp motor
that will be over 90 percent efficient. It uses elegantly designed CNC
machined anodized aluminum and nickel-plated steel parts in
combination with "off the shelf" bearings, races, snap rings, magnets,
etc.

The prototype AeroConversions motor is slightly larger than a 35 ounce
coffee can and weighs approximately 50 pounds. The motor is a
modular, scalable unit. The motor core's design has modular sections
that can be reduced to a lower-output, smaller motor (shortened in
length), or added upon to make a larger motor with a higher power
output.

· Electric Power; AeroConversions Electronic Motor Controller:
Electronic motor controllers for brushless electric motors are quite
commonplace today, mostly used in the electric RC market. A suitable
controller for a 270 volt, 200 amp motor does not exist. Running such
high current requires much larger components. Although there are a
handful of third party vendors who could design and build the
appropriate controller for this project, it would take 6-7 months lead
time and cost 20-50 Thousand Dollars. The time and cost associated
with acquiring such a controller was deemed unacceptable and the
research and development team, in cooperation with a key electronics
expert, began designing a proprietary AeroConversions electronic motor
controller.

The controller can commutate the motor in two different ways: using
Hall effect sensors to determine the magnet core's position in
relation to the coils, or using the motor's back-EMF to sense rotor
position, eliminating the need for Hall sensors. The AeroConversions
controller will initially employ a Hall effect sensor-equipped motor,
but back-EMF controlling will also be explored to potentially further
simplify the AeroConversions motor design. The AeroConversions
controller will also provide in-cockpit monitoring of battery power
levels to the pilot.

· Electric Power; AeroConversions Battery System: Most contemporary
electric powerplants for gas-electric and pure electric cars and
previous generations of RC electric vehicles utilize Lithium Ion
battery technology. While much improved in power density and discharge
rate over lead-acid and NiCad batteries, Li-Ion batteries still do not
offer enough power discharge-to-weight ratio to support an electric
powerplant for an aircraft that is based on battery power alone and
has a market-viable endurance. Newer RC electric vehicles, cell phone,
laptop computers and other mobile devices have been moving toward
Lithium Polymer cells. Li-Poly battery cells can safely discharge at a
rate of 25 times their capacity, or "25c."

With all the extra energy of a Li-Poly cell, however, comes extra
volatility. The E-Flight design team has engineered and constructed 10
battery "safe boxes" intended to contain 8 Li-Poly battery packs per
box and consolidate their charge/discharge and balancing wiring into
two sets of multi-pin connectors. The Boxes will accommodate natural
cell expansion and contraction while safely securing each cell pack
and facilitating cell cooling with "cooling foam" padding. Cooling
will further be aided by heat sink surfaces on each box that will have
cooling inlet air directed over them. Additionally, the boxes are
designed to contain and safely direct fire or explosion within the box
through a "blow hole" in the box that will be connected to a small
exhaust manifold.

For the proof-of-concept aircraft, the battery boxes will be removed
from the aircraft and charged individually. The charging units need to
be configured to safely keep all cells balanced during charging.
Lessons learned from the proof-of-concept systems will lead to the
design of more advanced charging and balancing systems allowing safer
battery handling by consumers, including a single-plug charging system
that may remain in the aircraft at all times, featuring easy exchange
of battery boxes to enable consecutive back-to-back flights in a short
period of time by pilots who wish to invest in spare batteries.

Future generations of safer, more powerful Li-Poly batteries show the
near-term possibility of further extended flight duration while
personal electronics and transportation will undoubtedly continue to
push improvement of the technology in years to come.

"By developing a viable electric motor and controller system for this
proof-of-concept aircraft, we will open a door to future flight that
we have only been able to dream of," comments Monnett. "Self-launching
electric powered gliders already exist. The potential of electric
power goes beyond that single use and relates directly to sport
flying, aerobatics and high altitude flight in purpose-built
airframes. It is essential that our proof-of-concept vehicle is a
conventional aircraft that the majority of aviation enthusiasts can
relate to."

One remarkable reality about the E-Flight electric aircraft project is
that, by necessity, the entire R&D project for the proof-of-concept
stage of the project will cost less than the price of the average
ready-to-fly LSA aircraft available today. This project undeniably
highlights the spirit of EAA in that it is truly a grass-roots effort
to push technology for advancement of our sport and improvement of our
planet's ecosystem and it has been accomplished, not by a large
aerospace firm or government agency, but by EAA members on an
extraordinarily cost-effective budget.

http://www.aeroconversions.com/

---------------------------------------------------------------------------*-----
The official daily newspaper of EAA AirVenture Oshkosh

Volume 8, Number 4 July 25, 2007

---------------------------------------------------------------------------*-----

Sonex rolls out electric plane
By Randy Dufault

Jeremy Monnett shows off the electric motor and mount employed in a
proof-of-concept Waiex airframe to demonstrate the potential of
compact electric power and advanced-technology batteries. Photo by
Dave Higdon

With the price of oil rising faster than an F-15 in an unrestricted
climb and the potential for $6 per gallon self-serve avgas a real
possibility, alternate ways of powering aircraft, ways that require
much less fossil fuel, are going to be important to the future of
sport aviation.

On Tuesday, Sonex Aircraft LLC took the wraps off its previously
secret e-Flight initiative.

"This is an exciting announcement and one that you are really going to
appreciate," EAA President Tom Poberezny said at the beginning of the
press conference. He added, "It addresses the grass-roots research
that is important to the integrity of EAA and the homebuilt movement.
More importantly, it is growing aviation by making it more
economical."

The most visible aspect of e-Flight right now is a Sonex Waiex
airframe equipped with a proof-of-concept prototype electric
powerplant. The aircraft, which is expected to fly later this year,
will be used to further develop the motor, along with the requisite
control systems, charging systems, and of course, battery systems.

"It was [apparent] that once we started down this path to developing
an alternative power source for the airplane, that we had to do it in
very specific steps," John Monnett, Sonex founder and president, said
when he introduced the electric plane. "The whole object of [the
proof-of-concept] is to come up with a powerplant that is equivalent
in weight and in power to our AeroVee-powered Sonex and Waiex
[models]."

Monnett went on to add the sole mission of the airplane displayed here
is to develop the technologies that will ultimately result in
production systems. The test-bed airplane is also expected to test
other, as yet unspecified, electric power sources.

The prototype powerplant uses brushless, cobalt motor technology and,
according to AeroConversions, is the most powerful, lightest weight,
and efficient motor of the type ever produced. It was developed with
the help of Bob Boucher of Astro Flight Inc. Astro Flight is a major
producer of electric radio-controlled model motors.

The 200-amp motor is 90 percent efficient and operates on 270 volts of
direct current electricity, as advertised by the Waiex's tail number,
N270DC.

According to Pete Buck, Sonex's chief engineer, the motor was
manufactured in-house. He added that Sonex expects to construct
virtually all of the components of the future production systems
themselves. Production systems, unlike the current AeroVee engine,
likely will not be offered as kits, due to the critical tolerances and
potential dangers with some of the electrical components.

Monnett pointed out that a couple of technologies are key to making
electric flight a reality. Of course, powerful and light batteries are
a must, but a motor controller capable of managing the high power
involved also is required. A charging system, capable of replenishing
the batteries in a reasonable amount of time, is another must. Sonex
is developing both technologies.

Target flight duration for the proof-of-concept airplane is 25 minutes
to 45 minutes. Production systems are expected to allow for one-hour
flights. Buck says an hour's endurance is difficult right now but
ultimately is very possible as both the system and the available
technologies are further developed.

In addition to the electric Waiex, Sonex's e-Flight initiative also
involves two other aspects: the practical use of ethanol fuels in the
AeroConversions AeroVee 2.0 engine and developing other enhancements
to the AeroVee, improving its already-impressive efficiency.

Sonex partnered with Wisconsin-based Renew Fuel Stations, a
distributor of E85, a blend of up to 85 percent ethanol and 15 percent
gasoline, to develop an AeroVee engine configuration that can use the
fuel. Renew's interest in the project is expansion of the market for
ethanol fuels. Testing is under way right now.

The idea of electric flight is not new to Sonex. It dates back to 1994
when Monnett and Buck looked into the possibility of building an
electric plane specifically for the purpose of establishing speed
records for a new class of aircraft. Although the project was deemed
to be practical, Sonex put the project aside to further develop its
current set of kit airplanes and to support their customers. The
company is committed to completing the effort this time, though
Monnett stated firmly that the e-Flight program will never detract
from Sonex's commitment to its customers.

Sonex is financing the entire effort itself.

Once production systems are available, Sonex plans to make them
available to the experimental market for installation on other
airframes.

Sonex will present a forum on the e-Flight project Wednesday at 11:00
a.m. in Forum Building 11. More information about the project is
available on the web atwww.AeroConversions.com/E-Flight.

================================================== ========

The RAeS General Aviation Group aims to encourage the development of
light aviation through the promotion of technologies, in particular
those that minimise its impact upon the environment.

The 2007-8 design competition therefore offers awards for technical
developments that can include:

· whole aircraft design
· propulsion
· operational methods
· specific technologies within the aircraft.

The competition is open to any individual or group; entries are
particularly encouraged from teams from educational institutions or
RAeS corporate members.

Entries should be received by Friday 2 May 2008 and consist firstly
of a 10 page report , showing how it works, its benefits both to
light aviation and to the environment, and who is responsible for the
entry.

A shortlist of entrants will then be selected, who will be invited to
give a 20 minute presentation at a special event at RAeS Headquarters
in London during mid June 2008. At that event, a judging panel will
select the final winning entries; prizes and final award categories
will be announced nearer to the entry deadline.

Judging criteria will be based upon feasibility, originality,
reduction of impact upon the environment and the potential benefits
to light aviation overall. Final presentations will also be judged
on presentation quality and response to questioning.

The judging panel will consist of highly qualified light aviation
professionals - including representatives from industry, regulatory
authorities and academia.

Further Details:
General Aviation Group
Royal Aeronautical Society
No.4 Hamilton Place
London, W1J 7BQ, UK


Very interesting. It doesn't mention how long it takes to charge the
batteries. It strikes me that if they could get the duration up to
about 2 hours or so, you could use an electric plane for basic flight
training. But you would need to be able to swap out the battery pack.

An electic motor should be more reliable than a piston engine. But I
wonder what the life span of the batteries would be. If they need to
be replaced periodically at the costs mentioned, it's possible that
electric propulsion would be as expensive if not more so than gas.

  #3  
Old August 5th 07, 07:12 PM posted to rec.aviation.piloting,rec.aviation.homebuilt,rec.aviation.ultralight,rec.aviation.soaring
Larry Dighera
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Posts: 3,953
Default Electrically Powered Ultralight Aircraft

On Sun, 05 Aug 2007 10:53:30 -0700, Phil wrote
in om:

Very interesting. It doesn't mention how long it takes to charge the
batteries.




There's a pod-cast here in which Sonex's owner John Monnett and
engineer Pete Buck discuss that topic:
http://www.aviationweek.com/media/audio/sonex.mp3

  #4  
Old August 6th 07, 08:14 AM posted to rec.aviation.piloting,rec.aviation.homebuilt,rec.aviation.ultralight,rec.aviation.soaring
James Sleeman
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Posts: 106
Default Electrically Powered Ultralight Aircraft

On Aug 6, 4:52 am, Larry Dighera wrote:
Electrically Powered Ultralight Aircraft


It's a nice idea, but realisitically there are too many problems, not
the least of which is battery size, weight, cost and safety. I don't
really see batteries as a viable in the near future (I struggle to see
them as viable in the distant future either).

That said though, I recently saw an article somewhere about an
electric car with a stirling engine tucked away in the back (Deam
Kamen was in on it somewhere - he's the Segway and fancy wheelchair
guy).

On the face of it, that seems like not a bad idea for how an electric
aircraft could be realistic - take your stirling engine, hook it
through a smaller, cheaper, lighter battery system to your electric
motor. The battery would act as a buffer (capacitor) to allow for
stored energy to do rapid changes in power to the drive motor, the
stirling engine would tick away at a constant rate feeding it's
generated electricy into the battery.

But then, I'm no engineer, I'm sure it's already been discounted as
impractical by the real engineers Maybe the stirling engine ends
up so big and heavy to produce the power required that it's useless.

  #5  
Old August 6th 07, 01:39 PM posted to rec.aviation.piloting,rec.aviation.homebuilt,rec.aviation.ultralight,rec.aviation.soaring
[email protected]
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Posts: 50
Default Electrically Powered Ultralight Aircraft

On Aug 6, 1:14 am, James Sleeman wrote:
On Aug 6, 4:52 am, Larry Dighera wrote:

Electrically Powered Ultralight Aircraft


It's a nice idea, but realisitically there are too many problems, not
the least of which is battery size, weight, cost and safety. I don't
really see batteries as a viable in the near future (I struggle to see
them as viable in the distant future either).

That said though, I recently saw an article somewhere about an
electric car with a stirling engine tucked away in the back (Deam
Kamen was in on it somewhere - he's the Segway and fancy wheelchair
guy).

On the face of it, that seems like not a bad idea for how an electric
aircraft could be realistic - take your stirling engine, hook it
through a smaller, cheaper, lighter battery system to your electric
motor. The battery would act as a buffer (capacitor) to allow for
stored energy to do rapid changes in power to the drive motor, the
stirling engine would tick away at a constant rate feeding it's
generated electricy into the battery.

But then, I'm no engineer, I'm sure it's already been discounted as
impractical by the real engineers Maybe the stirling engine ends
up so big and heavy to produce the power required that it's useless.


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.


  #6  
Old August 6th 07, 02:33 PM posted to rec.aviation.piloting,rec.aviation.homebuilt,rec.aviation.ultralight,rec.aviation.soaring
Airjunkie
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Posts: 19
Default Electrically Powered Ultralight Aircraft

Eric Raymond has been at it for a long time. Check it out at
www.solar-flight.com



  #7  
Old August 6th 07, 04:18 PM posted to rec.aviation.piloting,rec.aviation.homebuilt,rec.aviation.ultralight,rec.aviation.soaring
Bill Daniels
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Posts: 687
Default Electrically Powered Ultralight Aircraft


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.

Bill Daniels


  #8  
Old August 6th 07, 04:39 PM posted to rec.aviation.piloting,rec.aviation.homebuilt,rec.aviation.ultralight,rec.aviation.soaring
Larry Dighera
external usenet poster
 
Posts: 3,953
Default Electrically Powered Ultralight Aircraft

On Mon, 06 Aug 2007 00:14:14 -0700, James Sleeman
wrote in
. com:

On Aug 6, 4:52 am, Larry Dighera wrote:
Electrically Powered Ultralight Aircraft


It's a nice idea, but realisitically there are too many problems, not
the least of which is battery size, weight, cost and safety. I don't
really see batteries as a viable in the near future (I struggle to see
them as viable in the distant future either).


There is a fundamental problem with attempting to power an aircraft
with batteries: The propulsion system must not only move the vehicle
forward as it would with an automobile, but it must also
simultaneously maintain the aircraft's altitude; unlike an automobile
that only requires a small amount of energy to overcome rolling and
wind resistance once in motion, an aircraft can't coast without losing
altitude, so energy demands for powering an aircraft are considerably
more demanding than those for an automobile.

That said though, I recently saw an article somewhere about an
electric car with a stirling engine tucked away in the back (Deam
Kamen was in on it somewhere - he's the Segway and fancy wheelchair
guy).


Are external combustion engines as efficient as internal combustion
engines? Stirling engines are great for converting waste heat to
mechanical energy, but I'm not sure how appropriate they would be for
aircraft propulsion.

On the face of it, that seems like not a bad idea for how an electric
aircraft could be realistic - take your stirling engine, hook it
through a smaller, cheaper, lighter battery system to your electric
motor. The battery would act as a buffer (capacitor) to allow for
stored energy to do rapid changes in power to the drive motor, the
stirling engine would tick away at a constant rate feeding it's
generated electricy into the battery.

But then, I'm no engineer, I'm sure it's already been discounted as
impractical by the real engineers Maybe the stirling engine ends
up so big and heavy to produce the power required that it's useless.


The comparative light weight and high energy density of lithium-ion
polymer batteries makes them a potential enabling technology for
electrically powered aircraft as well as automobiles. All-electric
automobiles are entering the marketplace finally:

Our customers are a diverse group. All value the sports car
performance of zero to 60 mph in about 4 seconds and a top speed
of more than 130 mph, but many of our customers are also concerned
about the environment. Some, such as customer Stephen Casner, have
owned (and still own) older electric vehicles like Toyota's Rav 4.
(Read his Tesla Motors blog at:
http://cts.vresp.com/c/?TeslaMotors/...4be/9291be675f

Early customers include Google Co-Founders Sergey Brin and Larry
Page, actor George Clooney, comedian Jay Leno, and California
Governor Arnold Schwarzenegger. Tesla Motors continues to take
reservations for the 2008 model year Tesla Roadster at our website
at:
http://cts.vresp.com/c/?TeslaMotors/...4be/d99894a034

Tesla Motors is closing out July with another significant
milestone reached: We have now accepted more than 560 reservations
for the Tesla Roadster toward an anticipated first year production
total of 800 cars.
http://cts.vresp.com/c/?TeslaMotors/...4be/4ed5aad61f

And if this prototype is an indication, all-electric automobiles will
no longer suffer from an image of being slow and impractical:

http://www.gizmag.com/go/6104/1/
The 640 bhp MINI QED plug-in EV
(link to this article)

Page: 1 2

September 4, 2006 Q.E.D. is an abbreviation of the Latin phrase
"quod erat demonstrandum" which means, "which was to be
demonstrated". In simple terms, it indicates that something has
been definitively proven. Accordingly, the MINI QED electric
hybrid is aptly named as it dispels any doubts about the validity
of in-hub electric motors playing their part in the future of the
automobile. PML FlightLink designs and manufacture electric
motors, EV drive systems, joystick controls and controllers and
bespoke motors for specialist applications and the MINI QED was
built to showcase their expertise in wheelmotors, with a view to
supplying what we expect will be a booming market in electric
vehicle applications over coming decades.

The result is a MINI with four times the horsepower of a Cooper S,
supercar performance and the prospects of some very serious EVs in
the near future. The QED is a ripper, using four 120kW (160bhp)
wheel motors complete with invertors to convert momentum back into
stored energy under brakes. With one on each corner you have
Ferrari-like power and very controllable independent drive on all
four wheels.

In the MINI QED, this package offers a 0-60mph time of 3.7 seconds
and a 150mph top speed – supercar territory. An on-board petrol
engined generator offers enough electrons to run continuously at
motorway speeds without depleting the battery, and you can plug it
in at night and commute in full electric mode if you wish.

As the invertor can exert more retardation than brakes, the
conventional disc brakes have been discarded altogether.

The inwheel motors and magnesium alloy wheels, and tyres, have a
total mass of 24kg. The original assembly mass on the MINI One was
22.5kg. With so little difference in unsprung mass (the brake
hubs and discs have been removed), and full regenerative braking,
the ride is claimed to be no different.

More importantly, it means dynamic management of up to 750Nm
torque at each wheel, (3000Nm total) in either direction, to
ensure optimum use of available power. The system can also use
steering (driver intent and wheel alignment) and vehicle attitude
(gyroscopic sensors read pitch, roll and yaw) as inputs to the
traction control and vehicle stability systems. Put simply, the
vehicle stability system will be the key, and it will ultimately
be the software that determines what the optimum tractive
distribution will be at each instant - how the energy stored in
the 300V 70Amp Hour (700Amp peak) Lithium Polymer battery is most
effectively distributed.

...continued: http://www.pmlflightlink.com/archive/news_mini.html

So it would appear that high-performance all-electric automobiles are
viable and in fact being produced commercially now. And while there
have been some successful electrically powered, unmanned aircraft
demonstrated, such as those of Dr. Paul MacCready's AeroVironment:

http://www.avinc.com/uav_lab_project_detail.php?id=40
Pathfinder flew to 50,567 feet at Edwards September 12, 1995, its
first trip to the stratosphere. From there, it was improved and
taken to the Pacific Missile Range Facility (PMRF), Kauai, Hawaii
for test flights in 1997, where it flew to 71,504 feet on July 7,
before performing a series of science missions over the Hawaiian
Islands.

http://www.avinc.com/uas_dev_project_detail.php?id=115
Global Observer is the latest development in High Altitude Long
Endurance (HALE) UAS, being the first operational configuration
able to provide long-dwell stratospheric capability with global
range and no latitude restrictions. Global Observer's unique
combination of both extreme flight duration and stratospheric
operating altitude is designed to deliver advantages in cost,
capacity, coverage, flexibility, and reliability that make it a
compelling complement to existing satellite, aerial and
terrestrial assets.

Missions Communications Relay & Remote Sensing
Features High-Altitude, Long-Endurance platform (all latitude
capability)
Endurance/Range Over 1 week/global
Payload Up to 400 lbs. for GO-1 & 1,000 lbs for GO-2
Operating Altitude 65,000 feet
Expected Availability Within 2 years for U.S. government, with
funding

There are also manned, commercially produced, electrically powered
sailplanes available in the marketplace:


http://www.lange-flugzeugbau.de/htm/...tares_20E.html
Antares 20E

http://lange-flugzeugbau.com/pdf/new...%20issue01.pdf
Today Lange Flugzeugbau received the EASA type certification for
the Antares 20E. (EASA TCDS No. A.092). This is the first time in
the world that an aircraft with an electrical propulsion system
receives a type certificate.
http://www.nadler.com/public/Antares.html


http://www.dg-flugzeugbau.de/elektroflieger-e.html
DG-800E the uncompromised Motor glider with Electro-Power?


Here's a little history:

http://www.solarimpulse.com/the-hist...tion-en20.html
Solar aviation began with reduced models in the 1970s, when
affordable solar cells appeared on the market. But it was not
until 1980 that the first human flights were realised. In the
United States, Paul MacCready's team developed the Gossamer
Penguin, which opened up the way for the Solar Challenger. This
aircraft, with a maximum power of 2.5 kW, succeeded in crossing
the Channel in 1981 and in quick succession covered distances of
several hundred kilometres with an endurance of several hours. In
Europe, during this time, Günter Rochelt was making his first
flights with the Solair 1 fitted with 2500 photovoltaic cells,
allowing the generation of a maximum power of 2.2kW.

In 1990, the American Eric Raymond crossed the United States with
Sunseeker in 21 stages over almost two months. The longest lap was
400 kilometres. The Sunseeker was a solar motor bike-sail plane
with a smoothness of 30 for a tare weight of 89 kg and was
equipped with solar cells of amorphous silicon.

In the middle of the 1990s, several airplanes were built to
participate in the "Berblinger" competition. The aim was to be
able to go up to an altitude of 450m with the aid of batteries and
to maintain a horizontal flight with the power of at least 500W/m2
of solar energy, which corresponds to about half of the power
emitted by the sun at midday on the equator. The prize was won in
1996 by Professeur Voit-Nitschmann's team of Stuttgart University,
with Icare 2 (25 meters wingspan with a surface of 26 m2 of solar
cells.)
http://www.solarimpulse.com/the-solar-impulse-en5.html


And here's a glimpse at the futu

http://www.boeing.com/news/releases/...70327e_pr.html
MADRID, March 27, 2007 -- In an effort to develop environmentally
progressive technologies for aerospace applications, Boeing
researchers and industry partners throughout Europe plan to
conduct experimental flight tests in 2007 of a manned airplane
powered only by a fuel cell and lightweight batteries.

The Boeing Fuel Cell Demonstrator Airplane uses a Proton Exchange
Membrane (PEM) fuel cell/lithium-ion battery hybrid system to
power an electric motor, which is coupled to a conventional
propeller. The fuel cell provides all power for the cruise phase
of flight.

During takeoff and climb, the flight segment that requires the
most power, the system draws on lightweight lithium-ion batteries.
(Boeing graphic)



Photo of Sonex e-flight electric aircraft's electric power plant:

http://www.sonexaircraft.com/news/im...light_5947.jpg


More info:
http://en.wikipedia.org/wiki/Electric_airplane
  #9  
Old August 6th 07, 04:42 PM posted to rec.aviation.piloting,rec.aviation.homebuilt,rec.aviation.ultralight,rec.aviation.soaring
Larry Dighera
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Posts: 3,953
Default Electrically Powered Ultralight Aircraft

On Mon, 06 Aug 2007 05:39:01 -0700, wrote in
. com:

When they start selling cars only powered by batteries I'm going to
invest in a tow truck business.


The time has arrived:
http://www.teslamotors.com/index.php
  #10  
Old August 6th 07, 04:53 PM posted to rec.aviation.piloting,rec.aviation.homebuilt,rec.aviation.ultralight,rec.aviation.soaring
Orval Fairbairn
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Posts: 824
Default Electrically Powered Ultralight Aircraft

In article . com,
James Sleeman wrote:

On Aug 6, 4:52 am, Larry Dighera wrote:
Electrically Powered Ultralight Aircraft


It's a nice idea, but realisitically there are too many problems, not
the least of which is battery size, weight, cost and safety. I don't
really see batteries as a viable in the near future (I struggle to see
them as viable in the distant future either).


Look at the problem this way: In an all-electric machine, you carry ALL
of your energy supply with you: fuel and oxidizer -- to make electricity.

With any IC engine, you carry the fuel only -- the air is free (20%
oxygen), so, at 15:1 air/fuel ratio, you would need 90 lb of air for
each gallon of fuel.

Therefore, for a nominal 50 gallon fuel capacity (300 lb), you would
have to carry an additional 7500 lb of air.

That is a lot of weight for a 3000 lb aircraft!
 




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