Using R/C engines in experimental aircraft

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hogheadv2

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2009-Polaris-Sportsman-XP-550-8.jpgIf your thinking that way, ATV engines with the divorced trans set-up may be a viable choice for low cost high torque [ Tq does the work, HP is just a math equation of tq and speed.] Put a second plug in the head, have the flyback from the mag/coil [off lawn tractor charge battery] Pushes those heavy ugly things 45-60mph through the dirt..... Air is a breaze =D
 

Dana

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Like a bike engine, an ATV engine isn't made for sustained high power.

"Torque does the work" is not the whole picture, it's power that does the work at speed. You can't ignore rpm (or airspeed), and then you're talking about power.

-Dana

Puritanism: the haunting fear that someone, somewhere, may be happy.
 

Richard6

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Lithium Iron batterys have a greater engery density than ni-cads. But like ni-cads, you have to watch the discharge voltage. On the plus side of Lithium Iron batts, you can charge them with a standard lead cell charger.

Richard
 

autoreply

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Lithium Iron batterys have a greater engery density than ni-cads. But like ni-cads, you have to watch the discharge voltage. On the plus side of Lithium Iron batts, you can charge them with a standard lead cell charger.

Richard
As far as I've understood it, you need a lot of care during charging. The wrong approach can blow up your plane and change the flight in a ballistic trajectory and might it surive the blast, it'll quickly burn. It's also necessary (dependent on where you fly) to heat up the batteries before and during use to get any useful power. Given the large number of cells (and the accompanying large risk of a single one going south) I'd advise extreme caution.

Two 747's have recently crashed because the passive freight (indeed, lithium batteries) lit up...
 

matthass

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Oct 11, 2009
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Hi Guys,

ok so its not quite an RC engine but UAV designed by 3W.
546cc and 40hp and 16kg..

:shock:

Just got it so still havent started it up and will let you know how it goes!
 

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BBerson

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Very interesting indeed!!! I wonder if rain would be a factor for the electric motors?
I just returned from Oshkosh.
Dale Kramer flew his electric Lazair ultralight everyday at Osh using RC model batteries and controllers. The Joby motors were not harmed by rain (I asked).
 

Dana

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Hi Guys,

ok so its not quite an RC engine but UAV designed by 3W.
546cc and 40hp and 16kg..

:shock:

Just got it so still havent started it up and will let you know how it goes!
Are you going to mount a redrive and/or starter on it?

Keep us posted...

-Dana

America is at that awkward stage. It's too late to work within the system, but too early to shoot the bastards.
 

Richard6

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As far as I've understood it, you need a lot of care during charging. The wrong approach can blow up your plane and change the flight in a ballistic trajectory and might it surive the blast, it'll quickly burn. It's also necessary (dependent on where you fly) to heat up the batteries before and during use to get any useful power. Given the large number of cells (and the accompanying large risk of a single one going south) I'd advise extreme caution.

Two 747's have recently crashed because the passive freight (indeed, lithium batteries) lit up...
Your are thinking of the Lithium Polymer batteries like typically used in laptops and model airplanes. The Lithium Iron batteries are almost indestructible. Yes they may not work well when very cold, but then neither do I. Here is a link to a discussion on the Lithium Iron batteries:

LiFePO4 Lithium batteries EV battery Lithium Iron Phosphate batteries electric vehicle ebike electric car battery
 

autoreply

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Your are thinking of the Lithium Polymer batteries like typically used in laptops and model airplanes. The Lithium Iron batteries are almost indestructible. Yes they may not work well when very cold, but then neither do I. Here is a link to a discussion on the Lithium Iron batteries:
I stand corrected :)
 

dino

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florida
Hi Guys,

ok so its not quite an RC engine but UAV designed by 3W.
546cc and 40hp and 16kg..

:shock:

Just got it so still havent started it up and will let you know how it goes!
Please do.

Dino
 

challenger_II

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Fisher County, Tx. USA
Lithium Ferrite batteries are way more robust than lithium polymers, though they do not have the same energy density.
From the experiments I have conducted, the "round cells" are better suited to high discharge, and charge, rates than the "soft pack" LiFe (the one's that look like the LiPoly's used in model planes) batteries. Niether will self-ignite, and burn your plane down, like a LiPoly in thermal overload (caused by over discharge, etc.). On the round cells, you should have a low-voltage cut-off set for 2 volts per cell, to prevent damaging the cell.
Having played with lithium-driven electric power systems, for larger model planes, I can tell you that you'd better have some DEEP pockets!


Your are thinking of the Lithium Polymer batteries like typically used in laptops and model airplanes. The Lithium Iron batteries are almost indestructible. Yes they may not work well when very cold, but then neither do I. Here is a link to a discussion on the Lithium Iron batteries:

LiFePO4 Lithium batteries EV battery Lithium Iron Phosphate batteries electric vehicle ebike electric car battery
 

topspeed100

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Oulu/Finland
Hi Guys,

ok so its not quite an RC engine but UAV designed by 3W.
546cc and 40hp and 16kg..

:shock:

Just got it so still havent started it up and will let you know how it goes!
This is awesome...2 of those and you could go after the FAI records in under 661 lbs calss.
 

delta

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May 26, 2011
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Brookside Utah
I tend to judge people (and the things they're selling) on the quality of their writing, and based on the description of the engine...

-Dana

Clothes make the man. Naked people have little or no influence on society.
Snake oil? I couldn't find any pro's or con's via google. For the price and the fact that I'd need two or three of them, I guess Continental wins.

Rick
 
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