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Ranger electrically powered?!?

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henryk

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But they do have very skilled pilots and favorable weather conditions.


BJC
-tailles Kaspers glider BEKAS-N can soar long time low level in athermic weather
(windy,gusty) transforming gusts energy into level increase...
 

litespeed

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Fritz,

What is your expected power needs including cruise in hp or KW?

What engine do you expect to use?
What is the weight of that engine package including fuel and all systems related to it ?
What is your expected payload ?
Total AUW?

With that in mind we can look at what can be done as electric or hybrid.
 

12notes

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And...Lazair is capable to cruise 3 hrs + on electric...but is thus no longer a Part 103 ac but an LSA.
This is completely false. The electric Lazair may have managed a 3 hour flight if it thermaled/ridge soared (which it is capable of doing) with the motor off, it did not cruise for 3 hours. Lazair itself says it only has enough battery for "about 1 hour of flight endurance", which is identical endurance to every other light electric plane available at the moment. This is not a surprise, since they're all using the same battery, lithium ion with an energy density of ~260 Wh/kg. They even have a pilot report on their website of a pilot landing with 20% charge left after 35 minutes.

http://lazairinfo.com/electric-lazair/
http://lazairinfo.com/electric-lazair/fourteenth-pilot-report/

It also has 2 Joby JM1 motors, each are rated at 13.2 kW continuous, I don't know how you got 3 kW total for the aircraft. Cruise power is generally 60-75% of maximum power, not 11%.
 
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Speedboat100

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This is completely false. The electric Lazair may have managed a 3 hour flight if it thermaled/ridge soared (which it is capable of doing) with the motor off, it did not cruise for 3 hours. Lazair itself says it only has enough battery for "about 1 hour of flight endurance", which is identical endurance to every other light electric plane available at the moment. This is not a surprise, since they're all using the same battery, lithium ion with an energy density of ~260 Wh/kg. They even have a pilot report on their website of a pilot landing with 20% charge left after 35 minutes.

http://lazairinfo.com/electric-lazair/
http://lazairinfo.com/electric-lazair/fourteenth-pilot-report/
I think I just saw a video where they claimed over 3 hour endurance. But the plane is no longer Part 103 but a LSA.

I try to find the video.
 

12notes

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I think I just saw a video where they claimed over 3 hour endurance. But the plane is no longer Part 103 but a LSA.

I try to find the video.
I think what the company claims on their website is a lot more reliable than a random video, especially if the claim is less impressive on their website.
 

stanislavz

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1 hours endurance for far 103 is totally ok in my mind. It is still not a tourer of any kind. And just as i had calculated for autogyro with rotax 447 (~40-45kg engine with mufflers starter fuel with tank etc.. ) - it is same in weight as same power ev motor with 7-10kwh batteries. So it will have to cruise on 50% of power for 30-40 minutes.. But you can and should go in different way with electric power - batteries in wing-tip, or in separate pod, few motors with separate propellers etc.. Not one big chunky motor with dangerous batteries in front of you.
 

Speedboat100

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I think what the company claims on their website is a lot more reliable than a random video, especially if the claim is less impressive on their website.

Sorry Lithium-Nickel-Manganese-Cobalt kinda batteries...2 hrs +:
 
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litespeed

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He may mean minimum power for level flight.

But what is that figure?

But given it has 26.4 kW (35hp) continuous, and a great deal more for bursts of short duration, I can't imagine you would be needing 65% of that much power for cruise. At approx 23hp for cruise , I expect it would be quite fast for part 103. So the true cruise might need quite a bit less power.

The mk1 had only two 5 HP motors- gutless and slow to climb.

Mk2 generally had rotax 185 which are 9.o HP (7kw) each , so 14 kW total at max power. 65% is 9 kW or 12 HP.

Pushing 23hp at cruise with the electric is way more than needed and probably way over part 103 speeds.

Sure you can prop it to go heaps slower but it will still climb like a angel given its got so much grunt when propped for max efficiency at cruise speeds. It should use only about 37% power at similar cruise speed as two rotax 185 when the are at 65%. Actually given lower drag might be 35% for electric.


The one in the report of course has floats and weighs a porky 400lbs. So a big diet would help and reduce a lot of drag. As such changes the figures a bit.

The gutless pioneer motors had 10 HP total at 65% assuming it can cruise in that little power is 6.5hp or about 4.8 kW.

So not 3 but potentially 4.8kw. So a min speed might actually get the 3kw just floating along slow under power. But I reckon it would be not far off stall speed.

That of course assumes it could get reasonable figures on only two 5 HP motors of the original.
 

BJC

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I consider the Lazair to be a well done design, both aerodynamically and structurally, but I am curious as to any real interest in owning and operating one, either electric or gasoline powered.

When they were being produced, there were lots of young hang glider pilots who were satisfied just to get into the air. The Lasair provided that function well, as long as weather conditions were favorable. (It has a very light wing loading and a stall speed under 20 mph.)

So, who would like to own one, and where would you keep it and fly it?

Thanks,


BJC
 

pictsidhe

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For under an hour. A kitfox was built with a zero power system. Updates stopped just before endurance testing. I suspect it was around 20 minutes...
 

Speedboat100

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A 2hr endurance electric ranger is not currently feasible.

Something lighter and aerodynamically sound could...even 3 hrs...and 400-500 km range....assisted with solar 700-1000 km ( not being a Solar Impulse III ). I'd say minimum span at 14-15 meters.
 

Speedboat100

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Strap a power system to a glider, otherwise, you are just dreaming.

You can get around 16 KW from solar cells in 14 m spanned aircraft.

Very few understands that Solar Impulse's electric engines couldn't even use all the current the cells produced during day time in it..they charged the batteries for night flying. That is why it was so huge.
 

erkki67

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Weight is the enemy #1, even for the Ranger.

2h of flight time in an electrically powered Ranger, makes electric flight interesting.

When ever there is the talk for high performance clean design requirements, this nonsense for the Ranger, as this bird is a flying barn door, and its never going to be something else then a flying barn door.

So, let’s think about the tech required to make this barn door flying electrically powered for 2 hours.
 
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