Quantcast

Why battery-powered aircraft will never have significant range

HomeBuiltAirplanes.com

Help Support HomeBuiltAirplanes.com:

mcrae0104

Well-Known Member
HBA Supporter
Log Member
Joined
Oct 27, 2009
Messages
3,524
I say 300 km is already significant.
Range of well less than 1% of the circumference of Earth is not a significant accomplishment unless the mission is only to fly across town and then recharge overnight (unless you're comparing aircraft to horse-drawn carriages).
 

Speedboat100

Well-Known Member
Joined
Nov 8, 2018
Messages
1,615
Location
Europe
Range of well less than 1% of the circumference of Earth is not a significant accomplishment unless the mission is only to fly across town and then recharge overnight (unless you're comparing aircraft to horse-drawn carriages).

Everything is relative...now they cannot leave the home base.
 

mcrae0104

Well-Known Member
HBA Supporter
Log Member
Joined
Oct 27, 2009
Messages
3,524
Everything is relative...
Puh-leez. If I can acquire a horse and feed it for less than an "advanced" airplane and cover more territory per day, then the airplane is no technical accomplishment, whether it runs on oats or pedal power or solar energy or nuclear fusion. Yeah, it's relative, TopSpeedBoat100.

 

John.Roo

Well-Known Member
Joined
Oct 8, 2013
Messages
455
Location
Letohrad / Czech Republic
Range of well less than 1% of the circumference of Earth is not a significant accomplishment unless the mission is only to fly across town and then recharge overnight (unless you're comparing aircraft to horse-drawn carriages).
Hello!
So it means that when electric airplane will achieve 400 km range it will be reasonable minimum? :)
Best regards!
Martin
 

Speedboat100

Well-Known Member
Joined
Nov 8, 2018
Messages
1,615
Location
Europe
Hello!
So it means that when electric airplane will achieve 400 km range it will be reasonable minimum? :)
Best regards!
Martin

In a good tail wind a 300 km aircraft can easily fly 400 km. That is plenty, but it is no transcontinental miracle ship.
 
Last edited:

Speedboat100

Well-Known Member
Joined
Nov 8, 2018
Messages
1,615
Location
Europe
How are you going to charge it to get home? Do we now have to add the weight of an onboard charger?
Mr. poormansairforce...in the early days of the computer it was estimated that the whole global demand of the computers would be 4 units. Let's think same in chargers...and hope the second charger will be there where I am going ?

....and some oats...as I like oatmeal in the morning.
 

poormansairforce

Well-Known Member
Joined
Mar 28, 2017
Messages
1,068
Location
Just an Ohioan
Let's think same in chargers...and hope the second charger will be there where I am going ?
Let me know when that becomes reality. There's so little money in GA today that I find it very difficult to believe this will ever happen in my lifetime. You can't even get auto gas at most airports. I can't see airports flocking to put chargers in every hanger as well as for general use on the ramp. And please don't say the words 'solar panel'.....
 

Speedboat100

Well-Known Member
Joined
Nov 8, 2018
Messages
1,615
Location
Europe
Let me know when that becomes reality. There's so little money in GA today that I find it very difficult to believe this will ever happen in my lifetime. You can't even get auto gas at most airports. I can't see airports flocking to put chargers in every hanger as well as for general use on the ramp. And please don't say the words 'solar panel'.....

How about if electric flight will cause a revolution in GA aviation ?

Motors are light...this makes a very light and possibly safe flight possible.

Down side today is an inadequate range...just 100-200 km at best of the systems.

Vin-Fiz-1911.jpg


Maybe we have to look back to find the answers the GA industry is hectically looking for.

Above Vin Fiz a Wright model R in Long Island in 1911.
 

Tiger Tim

Well-Known Member
Joined
Apr 26, 2013
Messages
3,403
Location
Thunder Bay
I still like the idea of building an electric sport plane just for me. Something with an hour or two endurance would be fine and a single seat. I don’t want to span continents, just a fair weather runabout to get a thirty dollar hamburger (electrons are still cheap). Off the cuff I’m thinking some existing reasonably slippery two seater with one seat permanently unavailable due to battery weight should do it, nothing revolutionary. I’m not looking for investors, after all. I bet a Sonerai II or a Tailwind could do it.
 

Dan Thomas

Well-Known Member
Joined
Sep 17, 2008
Messages
5,549
They sport a very capable looking plane: Bye Aerospace eFlyer 2 - Wikipedia
And their numbers don't make sense. From Wikipedia:

"The 57 lb (26 kg) Siemens SP70D has a takeoff rating of 90 kW (120 hp) and 70 kW (94 hp) continuous. Utah-based Electric Power Systems provides the 92-kWh energy storage including battery modules, management and distribution."

  • Crew: one
  • Capacity: one passenger
  • Wingspan: 38 ft (12 m)
  • Wing area: 129 sq ft (12.0 m2)
  • Empty weight: 1,460 lb (662 kg)
  • Gross weight: 1,900 lb (862 kg)
  • Powerplant: 1 × Siemens SP70D[21] electric motor with up to six lithium-ion battery packs, 115 hp (90 kW)
  • Maximum speed: 135 kn (155 mph, 250 km/h)
  • Endurance: 3.5 hours
  • Maximum glide ratio: 20.6:1
  • Rate of climb: 1,050 ft/min (5.3 m/s
How does a 92 kWh battery provide 3.5 hours endurance at 70 kW? How does a 1900-pound airplane get a climb of 1050 FPM on 120 HP? What sort of 38-foot wing gives a 20.6: L/D at 1900 pounds?

There's either some hidden magic, or a lot of mathematical deception. They built one airplane four years ago and flew it two years ago. Got 200 deposits. Are they waiting and hoping for a still-nonexistent battery a lot better than what they have? That's what the Harbour Air electric Beaver is waiting for.
 

Speedboat100

Well-Known Member
Joined
Nov 8, 2018
Messages
1,615
Location
Europe
And their numbers don't make sense. From Wikipedia:

"The 57 lb (26 kg) Siemens SP70D has a takeoff rating of 90 kW (120 hp) and 70 kW (94 hp) continuous. Utah-based Electric Power Systems provides the 92-kWh energy storage including battery modules, management and distribution."

  • Crew: one
  • Capacity: one passenger
  • Wingspan: 38 ft (12 m)
  • Wing area: 129 sq ft (12.0 m2)
  • Empty weight: 1,460 lb (662 kg)
  • Gross weight: 1,900 lb (862 kg)
  • Powerplant: 1 × Siemens SP70D[21] electric motor with up to six lithium-ion battery packs, 115 hp (90 kW)
  • Maximum speed: 135 kn (155 mph, 250 km/h)
  • Endurance: 3.5 hours
  • Maximum glide ratio: 20.6:1
  • Rate of climb: 1,050 ft/min (5.3 m/s
How does a 92 kWh battery provide 3.5 hours endurance at 70 kW? How does a 1900-pound airplane get a climb of 1050 FPM on 120 HP? What sort of 38-foot wing gives a 20.6: L/D at 1900 pounds?

There's either some hidden magic, or a lot of mathematical deception. They built one airplane four years ago and flew it two years ago. Got 200 deposits. Are they waiting and hoping for a still-nonexistent battery a lot better than what they have? That's what the Harbour Air electric Beaver is waiting for.

Their estimate is based on low cruise consumption.

Their AR is just 12.....so 20,6 : 1 glide ratio may be a bit extented.

I'm trying to push my small under 70 kg planes limits and got 14,25 AR.....I might have now 20-24 L/D.
 
Last edited:
Top