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Discussion in 'Soaring' started by John.Roo, Dec 5, 2013.
Also interesting article
Fuel-Free Flight: The State of Electric Airplanes - Tested
Solar Flight SUNSTAR – a New High-Flyer – CAFE Foundation Blog
Hello dear friends,
maybe interesting for you...
Here you can download final version of our movie (sorry, so far only in Czech language).
1000 mil na
Very nice, Martin. Well done.
What is current status of ePhoenix project?
Thank you dear friend,
it was real adventure
Especially not expected landing in Duba airstrip and then emergency landing in the corn (cereal) field.
I beleive it was the best recorded emergency landing of electric airplane ever
However also this is part of development and it shows simple fact valid also for „normal“ airplanes – you have to expect engine failure at any time…
And what we are planning to do now?
I really don´t know…
I would love to try another challenge.
To fly over Mt. Blanc, across La Manche channel…
There are interesting (and very well sponzored) projects comming like for example:
Perlan Project (http://www.perlanproject.org/)
… and all this projects are aiming very high
Or we can focus ourselves on „business“ goal – how to make something like Tesla in the air.
Use our actual knowleadge and experience and convert it into airplane really able to be operated in private hands or aeroclub…
If some of you have suggestion for us – every idea is welcome
=single wire line...
=однопроводная линия электропередачи.
-it is possible to transmitt electric energy by high resistance \thin carbon wire or
laser beam\ single isolated from yearth line...
=very economic solution for electric glider launching!
E-Soaring is not only a question to fly to new records. It also can be realized with slow&light.
Two examples (under construction) you can find at the following links:
UL-Segelflug.de - GFW-4: Neuer Meilenstein im UL-Segelflug
UL-Segelflug.de - Revolutionary ULF-1 Concept "Made in USA"
Best regards from Germany
Hello dear Klaus,
thank you for links to interesting UL-Segelflug projects.
To use electric motor for light flying machines is even easier.
You need less power = lower weight requirements for installed battery.
There is only one problém - “financial paradox”.
Owners of small UL airplanes (Straton, Banjo etc…) are buing that airplanes due to low price.
But even low power electric solution is too expensive – they can use engine from Trabant for “nearly free” so to convince them to electric motor is not easy.
If you want to convert to electric power airplane normally using Rotax 912 then is “psychological difference of cost” smaller
And one nice example - my friend is making beautiful electric (or gasoline engine powered) trike based on wing from ATOS (ULTRALIGHT DESIGN s.r.o.)
Performance and weight is great – two seat version will be released soon.
I definitely don´t work on our electric plane only for record flights – but true is that record flights are “speeding up development”
During our flight “around” Czech Republic we had to solve a lot of small problems in very short time = great experience for future common use.
that is interesting idea…I don´t understand how to receive electric energy from scalar field, but if this theory will work then will be useful for all moving machines…
I am only sure that is not simple and easy – I don’t remember any system available on the market powered by scalar field.
be happy you live in Zcech Republic, where such things seem to be done much easier and with less problems by Aviation Authorities.
I am a great fan of electric-powered airplanes and I realy am convinced, that this is the future, especially for our
The GFW-4 designed by my friend Gerhard Wagner will be the first one of that kind, second will be a Horten delta
also 120kg-class by my friend Andres Chavarria-Krauser from Heidelberg. I have a blog at my website about flying-wings, where you can see this Horten as RC-Model used for test-flying. We all wait to see both ultralight-gliders to be
finished getting up into the air.
B.t.w.: I have seen such ATOS-Wing your friend builds, only with cobustion-engine. Just great and with E-drive even much better!!!
=NO wire curent loses,
only driver and transmitter loses,circa (10+10)%.
what about idea of in flight energy recovery/recharge?
=-22 C*,full comfort...
=2-place rigid wing trike=very interesting!!! \no wing/trike inertia problems?\
=scalar field can transmitt electric energy,no generation...
\electric energy from cheap but heavy "ground" power,f.e. accumulator\.
Hello dear friends,
generally I am open to all new ideas incl. “scalar energy transmission”.
Only I am afraid that is not so easy…
It means that actually we have to use what we have = Li-ion or LiPo cells.
Promising is also new technology of super capacitors or hybrid batteries (cells and capacitors).
Now I am following (just theoretically) idea of electric trainer.
I found this article
AEAC Pulls in First 20 Deposits – CAFE Foundation Blog
…and I have been thinking about how to modify our airplane to make nice small electric trainer.
Phoenix or electric Phoenix are airplanes nice to fly, but not ideal for standard pilot training purpose.
For that purpose I also recommend to have tricycle gear and “standard wing” (flaps instead of flaperons and spoilers).
High-wing configuration may would be even better, however I prefer low-wings
Possible performance with actual stage of batteries…
No problem for 80-100hp power for takeoff. Electric motors with that power are now available also with liquid cooling systems.
Due to known aerodynamics I expect to have requirements of approx. 12 kW of power for horizontal flight = approx. 70-75 kg battery.
It means we can replace in the front Rotax 912 with electric motor and battery with capacity able to keep airplane in the air for 60 minutes.
possibility to use all existing wing extensions (10,6 m wings span and 15 meters wing span)
reasonable requirements for hangar space (10,3 meters wing span without wing ext.)
due to “glider system” of assembly would be possible to dismantle airplane to trailer in 15 minutes practically without tools
possibility to make glider aero towing (yes, I know it is may too much dreaming – but who knows)
battery in the front = easy exchange of batteries
No fuel = reserve of weight for another 70-75 kg battery (in luggage compartment = also easy access) increasing endurance to 120 minutes (normally we have 2x50 liters fuel tank).
No development – all is already done.
Only small modification of fuselage necessary (taildragged to tricycle gear)…
=+solar foil cells...\accu lader\.
I am very interested to learn where is the off the shelf 80-100HP electric motor that can be bought as a complete plug and play system. The Emrax comes to mind in that HP range but then you need to buy the controller, charger, stack up the battery bank etc as they do not have a plug and play system at that HP. The eGull uses Zero's 55HP powertrain and that is as close to the plug and play system that you can get but again it is only 55HP.
We on this side of the pond do not have a lot of exposure to what is going on in Europe and would appreciate it if you can direct me to some of these developments as it can help the HBA community overall.
Emrax or FES are pretty much the only ones that are even close to "ready to fly" packages.
For a hybrid, the high power-density batteries make a lot of sense. Up to 3-4 kW/kg with an energy density of 400 kJ/kg is available on the market now. (Saft V6L for example)
Jarno, you have suggested both of these before but they both require a lot of head scratching for implementation. I am not an engine guiy and nor am I an electrical engineer to have confidence that I can get the Emrax up and running in an aircraft. The FES is very expensive Vs the Zero powertrain.
I know we will have a plug and play electric powertrain in the near future and want to keep myself involved. The comment about the availability of 80-100HP made me dig it a little deeper.
Your input on all the electrical side of propulsion is incredible. I appreciate it a lot.
Dear friends interested in electric motors suitable for airplanes,
please forgive me that I go now a little bit back to the history to explain you actual situation with electric motors…
In 2011 we did a first flight with our D-14 electric Phoenix – at that time we used our own electric motor with peak power of 44 kW. Controller was from company Kelly Controllers. With LiFePo cells we did 16-20 minutes flights.
In about the same time big aeronautical company Evektor started development of electric airplane EPOS.
Evektor - SportStar EPOS - an Electric Airplane Concept
The difference between our ideas was following – we did maximum to decrease power necessary for horizontal flight (retractible gear, “glider” wing etc…), they modified the airplane EUROSTAR (different wing tips to increase wing span), however main idea was to replace 80 hp Rotax 912 with electric motor. Czech Technological Agency supported project EPOS financially so in 2013 has been introduced electric airplane with 60 kW electric motor powered by LiPo cells from Kokam.
We also changed LiFePo cells to LiPo cells (GEBattery) so we achieved 45-50 minutes flights, however at that time still with our electric motor and Kelly controller...
In 2014, when EON and Czech TV were interested to make a document about our activities, we decided to stop development of our own electric propulsion systems and we started cooperation with companies Rotex and MGM.
And now starts part answering your questions
Yes, they are already available electric motors with power 60-74 kW. You can have air cooled or water cooled version.
More details you can find here:
For motor with power like this you need controller. We use now controller from MGM Compro (as EPOS / Evector, as E-Fan / Airbus, as experimental glider KKB-15/18 etc…).
More details here:
They offer wide range of controllers from 3-60/74 kW. They are also able to help with battery system (BMS) and chargers.
Due to our decision to use medium/low voltage controller with max power of 33 kW we had to reduce our nominal voltage from 144 V to 99,9 V.
Therefore we used only 34 kg part of our 50 kg LiPo battery and therefore we reduced flight time to only 30 min.
After more than 1 000 km in the air I can say that this system is working very well.
Of course I fully recommend you to read manual carefully and check datalogs after every ground test / test flight – you can precede unexpected landings for example in corn field (my personal experience well recorded in the movie)
1000 mil na
I hope this info will help you to stay safe in the air with “zero emission airplanes” dear friends.
Nor am I an expert in electric propulsion. I have talked to several suppliers and builders of hybrid/electric aircraft however, including FES.
You get what you pay for - in that sense it's not unlike conventional (piston) engines - and the more expensive systems are worth their money, unless you're willing to invest your own time like Martin.
I'm afraid the whole "let's put in a 500US$ engine plus battery" is an illusion for man-carrying aircraft. The fire risk alone warrants investing in proven system, meant for man-carrying craft.
Very well written, I fully agree…
We had the same idea – let’s built our own electric motor and let’s buy cheap controller. If is working in the RC models no reason why doesn´t work with a bit higher power.
Because of that mistake I am definitely holder of world record in number of emergency landings with electric airplane
I burned many times motor or controller in flight even if was everything looking OK during ground test.
The only difference is that combustible engines are difficult to build. Electric motor is relatively simple.
I am sure that when Chinese producers of controllers and electric motors will really enter to the market prices will drop down.
Due to Tesla monster production of Li-Ion cells we can also expect better prices for batteries.
So (as I wrote before) I thing that future really is “electric” for small sport aviation – especially for self-launch gliders / motorgliders.
However – I still recommend you to make a glider pilot license before you want to start flying with electric motors
But generally I recommend this to every pilot, because I had engine failure even with legendary Rotax 912 (mechanical fuel pump failure).
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