Most Efficient Airframe

weirdjim

weirdjim

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weirdjim
In the back of my head I'm starting (JUST STARTING) to think about building an electric vehicle.

It seems like we have several choices of airframe ... all the way from standard wing-fuselage design to dirigible and everything (powered parachute, powered hang glider, gyroplane, etc.) in between.

So, let's put together some sort of design limitations. Let's say we want to carry one or two humans for a distance of 200 miles between charges. That's pretty much the fundamental limitation, but I'm sure as we go on there will be others. It MIGHT be nice to be able to land on the offramp of a freeway and taxi to an electrical plug somewhere, but perhaps not.

What would be your choice of craft and why (current regulations are NOT a limiting factor in this exercise)?

Thoughts appreciated,

Jim
 
Tandem sailplane, with pod for motor/prop.

Or, that Virus thingy sans engine.

You won't make it 200 miles in pretty much anything else that will not have an IC engine. Maybe 140 miles or a bit more. Meh - you could slow down to max L/d and maybe make 200 miles.
 
What kind of environmentalist pinko crap is this? We don't need no stinkin' electric airplane - we need more coal-powered aircraft. And I don't mean no stinkin' clean coal - good old fashioned dirty coal-powered airplanes. With a tailwheel.

Now whan I've gotten that out of my system, I agree with doc - a powered glider like the Pipistrel Virus would be a good starting point.

Didn't Pipistrel at some point plan a hybrid and all electric version of the Panthera?
 
Why not go LTA? You could have the full captain's wheel that turns around and a fancy uniform and a few lower power higher endurance engines since they wouldn't be doing the work :D Plus of course more time to log if you weren't in a rush.

Plus I wish that that age didn't end. They just looked so cool, like real air ships! Now you're confined to a seat ;)
 
Flying Viking said:
What kind of environmentalist pinko crap is this? We don't need no stinkin' electric airplane - we need more coal-powered aircraft. And I don't mean no stinkin' clean coal - good old fashioned dirty coal-powered airplanes.
Click to expand...
Electric is coal powered.
 
overdrive148 said:
Why not go LTA? You could have the full captain's wheel that turns around and a fancy uniform and a few lower power higher endurance engines since they wouldn't be doing the work :D Plus of course more time to log if you weren't in a rush.

Plus I wish that that age didn't end. They just looked so cool, like real air ships! Now you're confined to a seat ;)
Click to expand...

Efficiency wise, LTA stinks if you're trying to go anywhere. You're fighting a lot of wind resistance to make any speed at all, and headwinds and crosswinds greatly degrade your X/C progress.

Now if endurance is your mission...
 
In the experimental forums there are folks who will discuss this endlessly with you
And there are already electric airplanes flying - so you are plowing old ground
Now they don't fly very fast or very long, but they fly
The limiting factor is the battery
And the weight
And cost


If you think our ancient technology gas engines are god awful expensive wait until you calculate what the cost of a LiPo battery set divided by the life expectancy comes to per hour
If you want to advance the art of flight, work on a natural gas powered engine
 
Dr. O said:
In the experimental forums there are folks who will discuss this endlessly with you
And there are already electric airplanes flying - so you are plowing old ground
Now they don't fly very fast or very long, but they fly
The limiting factor is the battery
And the weight
And cost


If you think our ancient technology gas engines are god awful expensive wait until you calculate what the cost of a LiPo battery set divided by the life expectancy comes to per hour
Click to expand...

Having just done a solar system for off grid - this post is spot on. The cost of light weight element batteries needed for aircraft, and the weight of the motor, cables, voltage regulator(throttle) makes battery flight at least impractical.

The only real upside to motor over engine is the excellent torque avail at very low RPM where props can be super long and efficient. Also I guess the motor is quite a bit more thermally efficient, but that doesn't translate well to driven energy. Sadly, a super long prop has ground clearance issues where you need a 5' tall gear to make it work well.

By the time you get enough battery and cabling on board to go anywhere the weight savings of the motor is rather paltry. Fun engineering project, but for efficiency in flight, the free air gas turbine engine is king.

<edited for clarity.>
 
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Put a wind generator on top to charge the battery.
Hehehehe
 
Somedudeintn said:
Although becoming less and less. I'm just waiting for natural gas prices to spike once the majority of the coal plants are shut down.
Click to expand...
Me too.
I have mineral rights for a tiny slice of a producing natural gas well in Texas. I used to get monthly checks around $200. Now I get a check about every 3rd month for around $100. Can't even go out for a hamburger for that.
 
Solar panels on the top of the wings. :D
 
High aspect ratio, laminar flow airfoil, conventional tail that's unloaded when trimmed for L/D max, everything you can do to reduce drag and weight...basically a glass slipper with electric assist. Prove you can do the fundamentals (200 miles between charges) then trade additional capability against performance

Nauga,
and his point design
 
Dr. O said:
In the experimental forums there are folks who will discuss this endlessly with you
And there are already electric airplanes flying - so you are plowing old ground
Now they don't fly very fast or very long, but they fly
The limiting factor is the battery
And the weight
And cost


If you think our ancient technology gas engines are god awful expensive wait until you calculate what the cost of a LiPo battery set divided by the life expectancy comes to per hour
If you want to advance the art of flight, work on a natural gas powered engine
Click to expand...

Any conventional Otto cycle engine can be converted to run well on natural gas. The trick is storing the stuff in the quantity needed to get anywhere. Work on fuel storage, not engine technology.
 
Capt. Geoffrey Thorpe said:
Electric is coal powered.
Click to expand...

Depends where in the country you are. Even here in this area where I live in the shadow of a coal powered steam station, it's only about 40% coal generated.

As far as coal powered aircraft goes, it's been done (allegedly). Gustave Whitehead's plane was powered by a coal fired boiler.
 
flyingron said:
Depends where in the country you are. Even here in this area where I live in the shadow of a coal powered steam station, it's only about 40% coal generated.
Click to expand...
It also depends on if you consider the average source of electricity or the marginal source that comes on line when you plug your battery charger in.
 
weirdjim said:
In the back of my head I'm starting (JUST STARTING) to think about building an electric vehicle.

It seems like we have several choices of airframe ... all the way from standard wing-fuselage design to dirigible and everything (powered parachute, powered hang glider, gyroplane, etc.) in between.

So, let's put together some sort of design limitations. Let's say we want to carry one or two humans for a distance of 200 miles between charges. That's pretty much the fundamental limitation, but I'm sure as we go on there will be others. It MIGHT be nice to be able to land on the offramp of a freeway and taxi to an electrical plug somewhere, but perhaps not.

What would be your choice of craft and why (current regulations are NOT a limiting factor in this exercise)?

Thoughts appreciated,

Jim
Click to expand...

Arion Lightning. www.flylightning.net
 
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