What do you think about "e-soaring"?

Homebuilt Aircraft & Kit Plane Forum

Help Support Homebuilt Aircraft & Kit Plane Forum:

WonderousMountain

Well-Known Member
Joined
Apr 10, 2010
Messages
2,750
Location
Bellingham, Wa
Looks very experimental.

Placing dihedral on the low wing set only holding the upper straight will give positive stability in the Roll axis. Anhedral reacts badly in multiwing X-plane simulations.
 

EzyBuildWing

Well-Known Member
Joined
Sep 23, 2009
Messages
606
Location
Sydney NSW Australia
a little off-topic, but this electric motive-power, like for aircraft, also makes a lot of sense for boating on inland lakes(I'm thinking of Lake Como, and the Aero Club Como which could offer smooth/silent excursions down to Villa d'Este for lunch!
 

henryk

Well-Known Member
Joined
Mar 8, 2010
Messages
7,313
Location
krakow,poland
Nenadovic biplane. I have no source to get better ones.



=?
 

John.Roo

Well-Known Member
Joined
Oct 8, 2013
Messages
1,863
Location
Letohrad / Czech Republic


=?
Hello!
Thanks - I know where to find info about Nenadovic or his theory.
But I could not find any "nice and modern looking" airplane following Nenadovic ideas ;)
 

John.Roo

Well-Known Member
Joined
Oct 8, 2013
Messages
1,863
Location
Letohrad / Czech Republic
a little off-topic, but this electric motive-power, like for aircraft, also makes a lot of sense for boating on inland lakes(I'm thinking of Lake Como, and the Aero Club Como which could offer smooth/silent excursions down to Villa d'Este for lunch!

I think it is interesting info 👍
As with airplanes.... I don´t see problem with e-motors and with e-motors installation.
Problem are batteries.
Boat usually need some weight on the bottom (low CG position is required) so battery weight is not as important issue as in case of electric airplanes.
Another advantage - on boat is not a problem to use "normal" solar panels ;)
 

Sraight'nlevel

Well-Known Member
Joined
Nov 4, 2021
Messages
371
I know Concordia project - interesting 👍
And performance is impressive...
"The predicted performance is very impressive with max L/D in the +70 range and an L/D of 50 at 210 km/hr with full ballast."
I figure long wings are a must, but how "short" wings could be in theory to get 70+ L/D ?

AR plays a pivotal role too I assume ?

Wingloading and interference drag are inportant too ?

Air speed has gotta be the best too: What is the definition of "best L/D"?
 
Last edited:

John.Roo

Well-Known Member
Joined
Oct 8, 2013
Messages
1,863
Location
Letohrad / Czech Republic
I figure long wings are a must, but how "short" wings could be in theory to get 70+ L/D ?

AR plays a pivotal role too I assume ?

Wingloading and interference drag are inportant too ?

Air speed has gotta be the best too: What is the definition of "best L/D"?
You are right - L/D optimalization depends on all details like AR, wingloading, drag reduction etc....
I agree with argument that L/D is not the most important parameter.
Of course is nice to have super high L/D, but you have to consider also typical use.
Concordia, ETA... all this super high end projects are pushing limits forward. It is "pure competition gliding".
However now we are in category 200K EUR plus....

What do you really need?
Unless you are competition pilot you need to have fun.
Fun for me =
... no stress with Takeoff. It should be self launch.
... no stress with assembling. Ideally light and simple enough to be assembled by one person.
... easy to fly etc.

In simple words - I need to be independent because when I want to go to the air I should go to airport and fly.

Performance is also important, but we are in category of "reasonable performance".
L/D 70:1 means high end glider - like a flying "rolls-royce".
If you have very low sink ratio at low speed, you can use weak or narrow thermals and quickly get altitude.
But light small glider cannot reach high L/D.... and here is (in my opnion) space for electric "L/D sponsoring".
Argument from glider pilot wil lbe that this is not "pure gliding" anymore....
But it doesn´t mean that this type of flying is not "pure fun" ;)

My "dream goal"?
Take off using electric motor. Use propulsion to first thermal, switch off motor and use lift up to cloud base.
Leave could base and let solar panels to feed electric motor and increase L/D with few kW of solar power.
Maybe can solar power already help during climbing - why not?
My "ultimate dream goal" will be achieved when we "harvest" enough solar energy for horizontal flight.... 😇

Actual goal?
Make prototype with electric motor (at the beginning without solar panels) and measure real data.
For example....
- how much energy I need for horizontal flight
- how far can I get with 5-6 kWh battery after 1x takeoff
- how fast can I recharge from "standard" electric plug
- what is temperature of solar panels on direct sun (installed on wing samples)
- how much solar energy I can really get with actually available solar panels
- etc...
....so many usefull informations I cannot get without real tests... 🤔
 

henryk

Well-Known Member
Joined
Mar 8, 2010
Messages
7,313
Location
krakow,poland

=I cant finde more "nice and modern looking" ...



-but was finde "funny" motor/generator !

 
Last edited:

blane.c

Well-Known Member
Supporting Member
Joined
Jun 27, 2015
Messages
6,151
Location
capital district NY
Looks very experimental.

Placing dihedral on the low wing set only holding the upper straight will give positive stability in the Roll axis. Anhedral reacts badly in multiwing X-plane simulations.

I was thinking that the upper wings straight and the lower wings dihedral would lock the wings stiff or have a tendency to. Wouldn't it be better to have at least a little dihedral in the upper wings as well, for more flexibility?

The "endplates" or "winglets" whatever they are when placed at a 45 degree angle should have flexible joints to allow a bit of movement between the wings?

Making it rigid kinda' give's me the creeps.

Though originally thinking tapered wings, I have changed my mind to a wing plan looking more like sunseeker except because Nenadovic' (Neanderthal) type wing you need to keep the rear wing leading edge straight (from plan view only) and upper wing trailing edge straight (from plan view only) then the taper at the outer section of the wings becomes obvious. This not only allows 4 Hershey bars to put solar panels on it also allows both wings to have equal dihedral until the outer section of the wings.

The outer tapered section of the wings is maybe were we "cheat". Maybe we stop the lower wing altogether and begin the endplate/winglet thingy and it tapers up to the upper wings tapered wingtip? Perhaps it is an all flying aileron? By increasing the dihedral of the upper wings tapered section we can increase the length of the aileron? Some deliberation as to how steep an angle an aileron can be and still be an aileron? But being on a angle obviously will reduce adverse aileron yaw, of course go to far and you need rudder input in the opposite direction per usual. So not to much of a good thing is better.

Using a Nenadovic' (Neanderthal) wing, only inverted for the horizontal stabilizer will also reduce drag and the size of the horizontal tail.

P.S. I suppose wing chord should be dictated by solar panel size and proper placement on the wings, Then span is a given per wing area requirement.

Pretty much need to know solar panel size to begin design.
 
Last edited:

WonderousMountain

Well-Known Member
Joined
Apr 10, 2010
Messages
2,750
Location
Bellingham, Wa
Blane: Wouldn't it be better to have at least a little dihedral in the upper wings as well, for more flexibility?

LouPai: Sort of, Box-wing end-plates are not going to induce no stress.

Blane: Making it rigid kinda' give's me the creeps.

LouPai: The Racking dynamic is structurally unappealing, but you ought be calculating & testing for off ideal loading anyway.

It sounds like you have thought out the planeform, but single taper single wing dihedral would be reasonably simple built.

Blane: So not to much of a good thing is better.

LouPai: It's fine that you're looking for an edge, but
it might need more mulling about.

Blane: Using a Nenadovic' (Neanderthal) wing, only inverted for the horizontal stabilizer will also reduce drag and the size of the horizontal tail.

LouPai: Yes that's a neat idea, but I wouldn't try it first testing.

Blane: Pretty much need to know solar panel size to begin design.

LouPai: I don't think it's critical, the modules are built of cells, so you will pretty much be within a few inches of goal Chord.
 

EzyBuildWing

Well-Known Member
Joined
Sep 23, 2009
Messages
606
Location
Sydney NSW Australia
Electron-tech.......better batteries on the way....

Contemporary Amperex Technology Co. Ltd. unveiled an electric-car battery it said has a range of over 1,000 kilometers (620 miles) on a single charge and is 13% more powerful than one planned by Tesla Inc., a major customer.

CATL is the world’s biggest maker of electric-car batteries, will start manufacturing the next-generation “Qilin” next year, according to a video the Chinese company streamed online Thursday. The battery charges faster than existing cells, and is safer and more durable, CATL said.

The Qilin battery, named after a mythical Chinese creature, has an energy density of up to 255 watt-hour per kilogram.
 

EzyBuildWing

Well-Known Member
Joined
Sep 23, 2009
Messages
606
Location
Sydney NSW Australia
Electron-tech.......some numbers: Electrons cost say 30 cents per kWh.........so that's 30 cents per 7.5 miles........pretty impressive for smooth and silent cruising......!

Mercedes-Benz announced it has tested its Vision EQXX electric car through a 750-mile trip on a single charge. The vehicle was driven from Stuttgart, Germany, to Silverstone, U.K., reaching highway speeds on its way to the Eurotunnel.
  • The trip took 14 hours and 30 minutes, driven at an average speed of 52 mph.
  • The road test is Mercedes' second for the Vision EQXX, having previously driven the vehicle from Stuttgart to Cassis, France.
  • The car has an energy consumption of 7.5 miles per kWh, with an energy content of the battery under 100 kWh.
 

kjlpdx

Member
Joined
May 20, 2022
Messages
8
Electron-tech.......some numbers: Electrons cost say 30 cents per kWh.........so that's 30 cents per 7.5 miles........pretty impressive for smooth and silent cruising......!

Mercedes-Benz announced it has tested its Vision EQXX electric car through a 750-mile trip on a single charge. The vehicle was driven from Stuttgart, Germany, to Silverstone, U.K., reaching highway speeds on its way to the Eurotunnel.
  • The trip took 14 hours and 30 minutes, driven at an average speed of 52 mph.
  • The road test is Mercedes' second for the Vision EQXX, having previously driven the vehicle from Stuttgart to Cassis, France.
  • The car has an energy consumption of 7.5 miles per kWh, with an energy content of the battery under 100 kWh.
my 2015 Leaf can only get about 4.2 average?
 
Top