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Is electric propulsion worth it?

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Speedboat100

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That style of RC biplane is actually happy to have the extra drag of the extra wing. Pattern flying judges judge on constant speed of the aircraft. They don’t want to perceive the plane speeding up or slowing down. Those planes have double the power to weight so up lines there is plenty of power to accelerate upward. Downwards the drag keeps the plane from accelerating due to gravity. Fuselage is fat because of that too. Very fun to fly. Very stable; not fast. Very agile.

I am not after crazy fast...but sustainable fast.


 

poormansairforce

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I counted that this gentleman had 1 kwhr battries weighing 25 lbs...almost twice what Tesla batteries would have weighed with same energy.
Okay so 1 kwh battery at 12.5 lb which equals 1.34 horsepower for 12.5 lbs. So a 50 horsepower motor would require a 466 lb battery. I'll take the gas please.
 

TFF

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That’s why a biplane is terrible for speed. At Reno the biplane class is about 40-50 mph slower than F1 with similar airframe rules and almost 75% more horsepower.
 

Speedboat100

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That’s why a biplane is terrible for speed. At Reno the biplane class is about 40-50 mph slower than F1 with similar airframe rules and almost 75% more horsepower.

I hear you...but having a low wing loading is a must in order to reach longer duration....on batteries.
 

Speedboat100

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The pedal power airliner went down in flames. Topspeed now plans to defeat known physics with a handful of AA batteries.
I have also solarpowered airplane design but it is forbidden subject here so don't start the rant again.
 

poormansairforce

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300 km...which ever speed is required. 120 mph:ish...150 tops.
okay in another post you indicated you want to do it in about an hour unless I'm mistaken.
I have also solarpowered airplane design but it is forbidden subject here so don't start the rant again.
It's not a forbidden subject here, anti-physics is forbidden here! 🙂
 

Speedboat100

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okay in another post you indicated you want to do it in about an hour unless I'm mistaken.

It's not a forbidden subject here, anti-physics is forbidden here! 🙂
Nothing anti physics involved here just excellent designing.

I have a flying model of the solar passenger plane...terrific glideratio.
 

Sockmonkey

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I've seen reports that some of the European car makers intend to be totally electric within a very short time frame, and just within the last couple of days I read an publisher's piece in an automotive industry (not consumer) magazine titled 'Canary in the Coal Mine', that said that there are no new internal combustion engines being developed at the major car makers. *That* is something to chew on.
Could be significant, but ICE tech has pretty well reached it's apex in terms of power and efficiency. That's not to say they can't be made better, but at this point it would involve making them more complex and expensive.

If I could understand how they can turn Radioactive Material into electricity, without generating steam driving a Generator, it might be a winner. I know they can generate electricity from heat fluctuations, but to what level of power I don't know.
I'm no physicist, but I would imagine the conversion works like a solar cell, only using atomic radiation rather than light to stimulate current flow. I really hope it's legit.
 

pictsidhe

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I'm no physicist, but I would imagine the conversion works like a solar cell, only using atomic radiation rather than light to stimulate current flow. I really hope it's legit.
The NDB has an infinite supply of energy. It extracts power from bullpoop.
 

Dan Thomas

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I hear you...but having a low wing loading is a must in order to reach longer duration....on batteries.
A biplane is not the way to reduce wing loadings. Biplanes are chiefly used in aerobatics because they can be built very strong yet light and have a good roll rate due to short wingspan.

Airliners have some very high wing loadings and yet they have high L/Ds too. Low wing loadings only give lower stall speeds, generally, and they are slow, too.
 
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rv7charlie

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Well, to stir the pot a bit :)
edit: sorry, google killed the link
which was last legal at Reno around 1983, and
edit: sorry, google killed the link
which is still legal, and still winning.
And to push the definition envelope a bit,
https://www.planeandpilotmag.com/images/stories/iad/2010/aug/homebuilt/viking-dragonfly.jpg

I could see a purpose-designed tandem wing as a viable option for electric operation. Two more intersection drag items, but no other related drag, and lower structural weight to support extreme span. I wouldn't ask for air race level performance; just efficiency at reasonable speed.

Charlie
 
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