What do you think about "e-soaring"?

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henryk

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My proposal did not include springs.

-in youth we have bad L/D hanggliders...for longering fly time/distance
we was "pumping" wing via trapetze.= weavy trajectory needs smaller energy as strait one !


=trajectory for JANTAR glider...(circa 100 km/h)
 

John.Roo

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Comparison of top ICE Paramotor to latest Electric Paramotor is interesting....
If Electric range could be doubled to 2 hours,probably everyone would fly electric.....electric has so many advantages!

Compare top electric and gas paramotors | OpenPPG
I wonder how much power paraglider needs to stay in horizontal flight....
According to specification of Open PPG is max. power of motor 25 kW.
Personally I don´t like to take 25 kW of power from 4,4 kWh battery...

Weight is 12.7 kg (28 lb) for motor installation + 20,5 kg (45,2 lb) for 4,4 kWh battery.
So on your back is 33-35 kg of extra "propulsion weight".
Honestly I don´t beleive you can takeoff and fly 60 minutes with paraglider with 4,4 kWh battery...
Takeoff and climb will request a lot of battery capacity, however could be a "sustainer" - when you "takeoff" from top of hill and you need to seek for thermals during horizontal flight 👍
 

EzyBuildWing

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Sep 23, 2009
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Sydney NSW Australia
Bahamas Paramotoring.....real-cool......this pilot transports his complete flying-machine to the launch-area, in an electric bicycle-trailer.......!!!!
This is the first flying-machine I've seen that you can store in you garage at home then tow it in a bicycle-trailer to your local airport and take-off....
Scenery in this proximity-soaring vid is breath-taking (absolutely stunning)....!!!!
See also his other incredible vid: Getting Stranded on a Desert Island.

 

John.Roo

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Electric airplane ELECTRON from Australia....

1637211757404.png

Looks "a little bit" like Millenium Master - only with "straight" elevator :cool:
1637212000409.png

Australia... beautifull coutry with a lot of sun and legendary gliding conditions.
Pitty that new Australian projects looks more like "normal" tandem seat airplane....

"On the MGM-Compro web site, the motor is priced at 7,875 euros (9,065 U. S. dollars). At current market prices, lithium-ion batteries cost about $137 U. S. per kilowatt-hour. The pack would cost $6,302 at those prices. Adding costs for a battery management system and associated cables could mean a total powerplant price under $20,000."
Sorry but 6 302 USD is far too optimistic price for 46 kWh battery :D

Nevertheless - lets watch this project. I wish to ELECTRON team good luck! 👍
 

John.Roo

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Hello!
Winter is comming so it is more time to dream :D
Before I already mentionned idea of "as light as possible" and "affordable" electric one seater with power 15-20 kW and small 6-7 kWh battery (= 1x takeoff and endurance arround 60 min + small reserve).

Draft one - typical "FES like" way.
Concept 1.jpg
Draft two - "Windex like" way. Retractable pylon is theoretically possible (even in draft one) however than is problem with place for rescue system installation. I mentionned this version anyway ;)
Concept 2.jpg
Draf three - "EXEL like" way = pusher config. To keep front profile small it could be short pylon retractable.
Concept 3.jpg
So here are 3 drafts. Each has some advantages and disadvantages.
Performance is not most important however each concept has L/D better than 1:30.

Comments on what concept you would most like (and why) are welcome 👍
 

henryk

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here are 3 drafts.

+ 4-th "draft"= modyfied STEMME (ELFIN)


-NO mooved nase, only conical semiring,when drifted back=open place for CRpropellers.

-first propeller 3-blade, second 2-blade (lower interference noise).

-circa double RPM (light,cheap) motor in DIFFERENTIAL mode (autrunner or innrunner),
NO gear ,
only sliding contacts !

-good aircooling (big air inlet + ROTATING stator).

=NO need in circular nase (universal).

=?

PS=clean fuselage in soaring phase (max L/D) !
 
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jedi

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Aug 8, 2009
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Sahuarita Arizona, Renton Washington, USA
Hello!
Winter is comming so it is more time to dream :D
Before I already mentionned idea of "as light as possible" and "affordable" electric one seater with power 15-20 kW and small 6-7 kWh battery (= 1x takeoff and endurance arround 60 min + small reserve).

Draft one - typical "FES like" way.
View attachment 118103
Draft two - "Windex like" way. Retractable pylon is theoretically possible (even in draft one) however than is problem with place for rescue system installation. I mentionned this version anyway ;)
View attachment 118104
Draf three - "EXEL like" way = pusher config. To keep front profile small it could be short pylon retractable.
View attachment 118105
So here are 3 drafts. Each has some advantages and disadvantages.
Performance is not most important however each concept has L/D better than 1:30.

Comments on what concept you would most like (and why) are welcome 👍

I like Draft one - typical "FES like" way. Prop in front.

A quick and simple start when needed. Can see that all is well and working. Possible cockpit heat (limited) from motor cooling air. Thrust on centerline is the biggie.

Second choice is Draft two - "Windex like" way. Still a quick and easy start. Clean aerodynamics. But long run from batteries to motor.
 

ypsilon

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Austria
Comments on what concept you would most like (and why) are welcome 👍
FES - Type, anytime.
Advantage: (Structurally) Simple, Aerodynamically (clean in the sense that the prop doesn't need to chop turbulent air), quickly and easily deployed (This is very important in real-life gliding. Outlanding accidents usually happen with motorgliders (mostly sustainers) - and there is a reason for that).

Disadvantage: Little clearance when launching on grass, which probably means that you'd go for a retractable gear, which adds complexity and weight again.
 

henryk

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="suck" is not right word for fenomenon of propeller thrust generation...

-it is no possibility to pull air (N2 +O2 molecules),
they have big kinetic energy (E=mV^2= kT) , circa 150 kJ /m^3 !

=the only forces between molecules are push one.

-propellers are nonsymmetrical "vacuum pumps",
but NO turbomolecular (very high RPM, >50 000 /min)
 

blane.c

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Jun 27, 2015
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capital district NY
="suck" is not right word for fenomenon of propeller thrust generation...

-it is no possibility to pull air (N2 +O2 molecules),
they have big kinetic energy (E=mV^2= kT) , circa 150 kJ /m^3 !

=the only forces between molecules are push one.

-propellers are nonsymmetrical "vacuum pumps",
but NO turbomolecular (very high RPM, >50 000 /min)

Apparently "my humor" doesn't transcend the language barrier. "Suck" wasn't meant literally, but meant as humor. AKA "it sucks".
 

John.Roo

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Letohrad / Czech Republic
Thanks for interesting opinions.
According to installation seems FES simpliest, however I see 2 main problems.
1) electric motor lifetime - on typical grass airfield is a lot of dust (small stones, grass etc.) and in this type of installation is motor very low and there is high risc that after few year of intensive operations it can be a problem. Could be solved with liquid cooled motor.
2) as mentionned - lower gound clearance = smaller prop = lower efficiency during takeoff and higher noise. Typical FES prop diameter is smaller than 1 m. If would be larger it means higher undercarriage. Modern glider profiles don´t like high angle of attack so until tail of glider goes up you can have problems with ailerons efficiency. Really not nice during takeoff with crosswind (personal experience).

Plus one safety problem... FES instalation needs to install power lines really near (arround) pilot seat. Can be done perfectly, however during ground impact is pilot zone absorbing deformation = higher risc of power wiring damage. Don´t forget that carbon is well leading electricity. To achieve lower weight of power wiring we typically try to reduce current. However "affordabe" battery voltage is arround 100 V (24S fully charged) = still 150-200 Amps during takeoff....

Just to thing about ;)
 
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