# Electric Ultralight (Goat)

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#### Orsovolante

##### Active Member
Interesting.
In Italy a manufacturer proposes the "Zigolo", a very similar vehicle, and is currently preparing an electric version.
Some considerations. In my opinion it is absolutely necessary to provide some brake that prevents the propeller from being dragged when flying with the engine off. This thing dramatically worsens efficiency.
On the other hand, with an electric motor, even with a fixed pitch propeller, you could get a sort of reverse that replaces air brakes and other necessary mechanisms to shorten landings out of range.

#### Topaz

##### Super Moderator
Staff member
Log Member
Interesting.
In Italy a manufacturer proposes the "Zigolo", a very similar vehicle, and is currently preparing an electric version.
Some considerations. In my opinion it is absolutely necessary to provide some brake that prevents the propeller from being dragged when flying with the engine off. This thing dramatically worsens efficiency.
On the other hand, with an electric motor, even with a fixed pitch propeller, you could get a sort of reverse that replaces air brakes and other necessary mechanisms to shorten landings out of range.
Most propellers won't auto-rotate above a certain airspeed. With internal-combustion engines, there's a fairly substantial hysteresis between that speed, where the prop stops rotating, and the speed where you can get it started again. Fortunately, both speeds tend to be well above the minimum sink speed (and probably even the best-L/D speed, depending on the engine and prop) of a glider like the GOAT.

#### Orsovolante

##### Active Member
in the movie we see the glider that takes off and the propeller turns, in my opinion dragged by the relative wind.
also in other phases of the film my impression is that it turns not because the engine is driven, but because it is set in rotation by the wind.
An electric motor offers little resistance. I think the hysteresis between the two speeds is very minor.

#### saini flyer

##### Well-Known Member
Log Member
I am building a Zigolo and considered switching over to E power, but chose not to for now for a few reasons.
1. The E-power system will weigh a fair amount more and I am already 220lbs/100Kg and could not afford to push the gross any higher. Also with IC as I burn fuel the gross goes down and performance upn whereas on Epower weight is fixed as Performace/Charge degrades
2. I will fly out of a Class D controlled airport that tolerates UL flight but all UL's must vacate the area so the limited range of the electric would not work for the area I will fly out of. Were is a non towered airport with a fair amount of thermal activity the E power would have been ideal as I could power down and stay within the relative safety of the airport. As it is now, I need to vacate so chances are I will never shut the engine down completely unless I find a new place to fly. Being in Los Angeles area my UL legal places are limited and the one other good place with tons of thermal activity is blown out by 10am whihc is also less than ideal.

I guess what I am saying is make sure to consider the actual mission you want to do before being lured into E-Power for aviation.

#### Bille Floyd

##### Well-Known Member
I am building a Zigolo and considered switching over to E power, but chose not to for now for a few reasons.
1. The E-power system will weigh a fair amount more and I am already 220lbs/100Kg and could not afford to push the gross any higher.
...

I guess what I am saying is make sure to consider the actual mission you want to do before being lured into E-Power for aviation.
I think current solutions for E-power , work OK, for clean aircraft
with L/D's, of 22:1 or better ; draggy machines are probably
better off with petrol engines , (for now) ?

My main mission is to gain enough
altitude to soar with a glider ; 3 re-starts , to altitudes
to 500 or 800-ft AGL, will do just fine. 1 climb to 1000-ft
AGL, with energy to get me home from 30-miles out will
also work ; i wouldn't take-off, unless i was reasonable sure
i could soar, and a 4-meter RC glider can tell me that , before
i ever leave the ground.

SO -- is that 220Lb because you Like pasta ; or 220Lb
because your a Big Stout Dude, and i better watch what
i say ?
Watch what i say , because with 2 fake legs , i ain't gonna
be able to run away; that's why i keep cold beer around . Ha !!!

I weigh a solid 205Lb ; but 10Lb of that is in my carbon
and SS legs & feet ! I sink like a rock, in lake water.

Bille

#### Topaz

##### Super Moderator
Staff member
Log Member
in the movie we see the glider that takes off and the propeller turns, in my opinion dragged by the relative wind.
also in other phases of the film my impression is that it turns not because the engine is driven, but because it is set in rotation by the wind.
An electric motor offers little resistance. I think the hysteresis between the two speeds is very minor.
I was speaking of internal-combustion engines, not electric. In post #3, you were discussing both. Unless the prop is geared, a pure-electric installation would probably require a prop brake, yes.

#### Victor Bravo

##### Well-Known Member
HBA Supporter
For a Zigolo, you could use a Sig Kadet or a Senior Falcon instead of a 4 meter glider

#### saini flyer

##### Well-Known Member
How much is the REX30? Is there a specific prop that is recommended & at what costs?

ROTEX electric The engine REX 30 should be enough for use on the plane. The price is now $1,800 without VAT. The usable controller is HBC 50063 (50V) 14 battery cells or HBC 280120 (100V) 28 battery cells (manufactured by MGM-compro.com). Price around$ 2630 excluding VAT

Pretty spendy...

#### Bille Floyd

##### Well-Known Member
...
The usable controller is HBC 50063 (50V) 14 battery cells or HBC 280120 (100V) 28 battery cells (manufactured by MGM-compro.com). Price around \$ 2630 excluding VAT

Pretty spendy...
Try getting a price , for the controller, from these guys , (the German
outfit i first recommended ).
https://www.geigerengineering.de/avionik/produkte

For a Zigolo, you could use a Sig Kadet or a Senior Falcon instead of a 4 meter glider
I won't be flying a powered Zigolo ; with the Mods i do to my
rigid-wing HG, i should get 22:1+ L/D @ 45-mph.

Bille

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#### pictsidhe

##### Well-Known Member
BLDC motors are easy to brake to a near standstill. Just short out the windings. Controllers could be programmed to do that.

#### Bille Floyd

##### Well-Known Member
BLDC motors are easy to brake ...
Just short out the windings.
...
Is that how the controller on my 2-meter RC glider works
when i stop the motor ? When the break doesn't work
that thing windmills, in a BAD way ; L/D goes down the toilet.

Knowing that, (above) ---- i want a mechanically deployed prop-break
and NOT an electrical one. With the prop behind my head ,
(what if i need to bail out) , and toss Laundry ; a spinning,prop
might make for a Very Bad day !!

Bille

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#### henryk

##### Well-Known Member

=for take-off ... ???

##### Well-Known Member
Log Member
I think current solutions for E-power , work OK, for clean aircraft
with L/D's, of 22:1 or better ; draggy machines are probably
better off with petrol engines , (for now) ?

My main mission is to gain enough
altitude to soar with a glider ; 3 re-starts , to altitudes
to 500 or 800-ft AGL, will do just fine. 1 climb to 1000-ft
AGL, with energy to get me home from 30-miles out will
also work ; i wouldn't take-off, unless i was reasonable sure
i could soar, and a 4-meter RC glider can tell me that , before
i ever leave the ground.

SO -- is that 220Lb because you Like pasta ; or 220Lb
because your a Big Stout Dude, and i better watch what
i say ?
Watch what i say , because with 2 fake legs , i ain't gonna
be able to run away; that's why i keep cold beer around . Ha !!!

I weigh a solid 205Lb ; but 10Lb of that is in my carbon
and SS legs & feet ! I sink like a rock, in lake water.

Bille
Bille,
I am 220lbs and 6'4" tall. I could stand to lose 15 lbs and hope I can get to 205 lbs before the Zigolo is finished. Although that is a tough goal as I do like Pasta and Pizza...