What do you think about "e-soaring"?

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John.Roo

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The whole electric thing is so wrapped up in geopolitical nonsense it often overrides one's true perspective.

If one just wanted cheap self launcher just put a IC engine on the blasted contraption and go. Obviously reduced carbon footprint is the primary motivation for most wanting electric propulsion even if some (most?) of that reduction in carbon footprint is put off into the future regarding reduced carbon footprint in infrastructure and manufacture not currently existing.

So for those who believe it is a duty or obligation to reduce our carbon footprint it kinda' boils down to how much is a breath of clean air for your grandchild worth? Or blue sky instead of maybe some other color? And work backwards from there.

There isn't anything you can say to the others their heads are lodged to far up their *.
Why not?
As I wrote many times - actually we have unique freedom to use propulsion system we want.
Just... this "freedom" will not stay forever and unfortunatelly decission is not on us.
Politics are making decissions without any technical knowleadge.
We can discuss long time about opinions if makes sense or not but we are heading to situation when electric propulsion will be only "affordable" way to fly.
Am I too pesimistic? I hope so....
I personally don´t agree with ideas to stop production of cars with ICE in few years (as anounced in many EU countries) however when this will happend we will notice very high rise of fuel prices.
Some EU airfields and airports are already under pressure of local people to start to fly without emissions. Sounds crazy but again - this has nothing to do with "logical thinkning".
Finally we will be forced to fly with "zero local emissions" (I wrote "local" because obviously many countries are producing electric power with emissions).
And when this will happend I hope I will have nice and safe electric airplane for my sons and grandchildren ;)
 

John.Roo

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Well... to be realistic... actually are both my sons not really thinking about flying (or electric flying)...
They were very succesfull on Czech Bowling Championship 👍
Michal - silver medal (juniors boys up to 9 years age)
Martin - bronze medal (juniors boys 10-12 years)
And their good friend Eliska - gold medal (junior girls 16-18 years)
All of them from one small team 😊

Sorry for off topic....
1628697007360.png
 

John.Roo

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Just for perspective, the Rotax 912 Si is somewhere north of $20k, weighs 130+lbs. dry, uses about 30 lbs of fuel per hour, and the configuration of the propulsion is limited to the immediate vicinity of the engine (no distributed propulsion). Electrical is not cheap or easy, but the current standards have a not insignificant cost, weight, and limitations.
Yes, 912iS is not cheap and light and look for price and weight of 915iS...
Also fuel consumption is raising far over 20 lit / hour.
So I still love good old 912 or 912S... :)

Therefore I like ideas of "available / affordable propulsion sets" like mentionned by
EzyBuildWing
 

John.Roo

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=Greate congratulations ,for Father too !

BTW=how many E-flyers is in Czech Republic ?
Hello!
If I rememer well they are following electric airplanes in CR:

- D-14 Phoenix

- U-15E Phoenix

- electric EGO Trike

- Sagitta

- Epos (electric Eurostar - actually not flying)

- electric JA-400 from Jihlavan (actually no news - no info about flying)

- soon will fly electric Terej (self launch glider)

- certified gliders with FES. HPH 304S Shark and KKB-15 (now Diana 3 = fuselage from KKB-15 and wings from Diana 2)

- soon will fly electric aerobatic experimental homebuild looking like smaller Zlin-50

- if I remember well it was flying also electric paraglider

I hope I didn´t missed some project...
Martin
 

John.Roo

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Detailed info about electric propulsion system used on Aerolite 103...

Pricing
Electric Propulsion System with 2 Batteries and 2 Chargers. Price 9,750 USD (weight 101 lb / 46 kg)
Electric Propulsion System with 3 Batteries and 3 Chargers. Price 11,850 USD (weight 137 lb / 62 kg)
Electric Propulsion System with 4 Batteries and 4 Chargers. Price 13,950 USD (weight 173 lb / 79 kg)

15 kW max. cont. power
25 kW max. power
Each battery pack has 2,6 kWh capacity and his own charger.

According to all available info - for light self launch glider or light trike could be used battery system with two batteries. 46 kg weight, 5,2 kWh battery capacity and 15 kW of power are interesting numbers 👍

The only possible problem are relatively low max. RPM = need to use prop with larger diameter.
For trike is not a problem, but for self launch gliders this could be significant limitation.
 

flyndude

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Cincinnati, Ohio
The whole electric thing is so wrapped up in geopolitical nonsense it often overrides one's true perspective.

If one just wanted cheap self launcher just put a IC engine on the blasted contraption and go. Obviously reduced carbon footprint is the primary motivation for most wanting electric propulsion even if some (most?) of that reduction in carbon footprint is put off into the future regarding reduced carbon footprint in infrastructure and manufacture not currently existing.

So for those who believe it is a duty or obligation to reduce our carbon footprint it kinda' boils down to how much is a breath of clean air for your grandchild worth? Or blue sky instead of maybe some other color? And work backwards from there.

There isn't anything you can say to the others their heads are lodged to far up their *.
Reduced carbon footprint is not even on the list of why I chose electric. It's a side benefit. In sailplanes we are using small 2 stroke motors, not known for being the most reliable ( a friend has had 6 engine outs) Have you ever ridden in a sailplane under power with a 2 stroke? Unbelievably loud. Like sitting in a 55 gallon drum with the motor screaming. They vibrate like crazy, you hope they start when you need them. Electric is lightweight, smooth, quiet, and the prop WILL instantly turn when you push the button.
 

PiperCruisin

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Idaho
Reduced carbon footprint is not even on the list of why I chose electric. It's a side benefit. In sailplanes we are using small 2 stroke motors, not known for being the most reliable ( a friend has had 6 engine outs) Have you ever ridden in a sailplane under power with a 2 stroke? Unbelievably loud. Like sitting in a 55 gallon drum with the motor screaming. They vibrate like crazy, you hope they start when you need them. Electric is lightweight, smooth, quiet, and the prop WILL instantly turn when you push the button.
I would like to push "Like" on this multiple times. Also, there are some advantages to distributed propulsion which can provide better configurations versus the typical turtle deck deployment. Also, I don't like rope breaks and tows.
 

emotodude

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Messages
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Detailed info about electric propulsion system used on Aerolite 103...

Pricing
Electric Propulsion System with 2 Batteries and 2 Chargers. Price 9,750 USD (weight 101 lb / 46 kg)
Electric Propulsion System with 3 Batteries and 3 Chargers. Price 11,850 USD (weight 137 lb / 62 kg)
Electric Propulsion System with 4 Batteries and 4 Chargers. Price 13,950 USD (weight 173 lb / 79 kg)

15 kW max. cont. power
25 kW max. power
Each battery pack has 2,6 kWh capacity and his own charger.

According to all available info - for light self launch glider or light trike could be used battery system with two batteries. 46 kg weight, 5,2 kWh battery capacity and 15 kW of power are interesting numbers 👍

The only possible problem are relatively low max. RPM = need to use prop with larger diameter.
For trike is not a problem, but for self launch gliders this could be significant limitation.
Hey, I designed this system ;) It is most efficient with a large slow prop. The "standard" motor is 27kv which is about 2000 RPM at 72v nominal voltage. This works very well with a 3-blade 60" prop. The other motor option is 44kv which is good for ~3200 RPM nominal. And works well with a 2 blade 53" prop.
 

proppastie

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Hey, I designed this system ;) It is most efficient with a large slow prop. The "standard" motor is 27kv which is about 2000 RPM at 72v nominal voltage. This works very well with a 3-blade 60" prop. The other motor option is 44kv which is good for ~3200 RPM nominal. And works well with a 2 blade 53" prop.
If I wanted 6k rpm for a 32" prop is that an option?
 

EzyBuildWing

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Sydney NSW Australia
Anyone know if Pipistrel electric can have longer wingspan and go "motor-gliding" with only the pilot aboard?
Propeller would just "free-wheel" or consume minimal kw on a "zerodrag-zerothrust"setting.
As an aside, I notice Tesla Plaid seats are now being referred to as "acceleration-couches"........
Tesla Plaid now has a "cult-like" following...... aviation needs something similar.to excite .....anything on the horizon????
 

John.Roo

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Hey, I designed this system ;) It is most efficient with a large slow prop. The "standard" motor is 27kv which is about 2000 RPM at 72v nominal voltage. This works very well with a 3-blade 60" prop. The other motor option is 44kv which is good for ~3200 RPM nominal. And works well with a 2 blade 53" prop.
Hello!
I understand and agree that large slow prop is more efficient (and is also producing less noise), but sometimes is just not possible to use it...
Very good that you offer also other versions. +-3 200 RPM is OK 👍
 

John.Roo

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Letohrad / Czech Republic
Anyone know if Pipistrel electric can have longer wingspan and go "motor-gliding" with only the pilot aboard?
Propeller would just "free-wheel" or consume minimal kw on a "zerodrag-zerothrust"setting.
As an aside, I notice Tesla Plaid seats are now being referred to as "acceleration-couches"........
Tesla Plaid now has a "cult-like" following...... aviation needs something similar.to excite .....anything on the horizon????
Hello!
I tested both versions of Pipistrel electric airplanes (Velis and Alpha Electro). Both versions are based on high wing Virus - not on TMG Sinus. Theoretically should be not a problem to install electric propulsion to Sinus because fuselage is similar. Velis and electric Alpha have batteries in fuselage so the only question is if Sinus 15 m wing is designed for MTOM 600 kg.
I personally prefer a bit more electric Alpha - on Velis I missed air brakes (Velis has only flaperons).

So you look for "flying Tesla"? :cool:
Depend what do you want from electric airplane.
I don´t see problem with available power of electric propulsion systems.
For few minutes you can already have same available power like from Rotax 915 iS. Or even more.
But (as Tesla) you decrease range significantly if you accelerate too often and too much.
Problem is (as discussed on HBA many times in different threads) weight / capacity / price of batteries.
So I would like to start with price - lower price could "compensate" actual disadvantage of lower range.
And good would be on board charger (ideally arround 10 kW or more) to be independent because I am affraid that it will take some time till we will see superchargers on small airfields.

What I expect in future?
Better battery cells will come (sooner or later). Than we will wait till they are well tested in automotive industry and price will drop down. And at that time we will replace actual Li-Ion cells ;)
 

emotodude

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Messages
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What I expect in future?
Better battery cells will come (sooner or later). Than we will wait till they are well tested in automotive industry and price will drop down. And at that time we will replace actual Li-Ion cells ;)
Yes exactly. The Zero Motorcycles battery uses 220Wh/kg cells. The cell manufacturer Farasis is now producing 320Wh/kg cells for Daimler. It will be another 3-5 years before we can get them, but that is almost 50% increase in energy density! This means my electric Xenos will go from 100 miles range to 150 miles range, just by changing batteries :) A more efficient aircraft like the Onyx could probably do 200-300 miles! And an extreme efficiency aircraft like the Goshawk could go 500 miles! The future is bright :)
 
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