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Electric Sky Bird?

Old 03-03-2021, 09:35 AM
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ec121
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Default Electric Sky Bird?

Has anyone ever put a motor in a 132" Sky Bird? I have one, but we don't use the winch anymore. I want to know what size motor and prop
Old 03-04-2021, 08:19 PM
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speedracerntrixie
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I would go with this motor with a 12x6 folding prop, 50 amp ESC and the smallest battery that will result in the correct CG. Most guys are running between 850mah to 1,000mah 3S lipo with a minimum of 75C discharge rating. That said, any power setup that will fit in the nose and deliver 400-450 watts of power should do the job.

https://alofthobbies.com/dualsky-xm3040-9-1350kv.html
Old 03-08-2021, 05:37 PM
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I like the motor suggestion but to allow for a couple or three climbs and still have a good reserve power I think I'd want more like a 1500mah 3S pack for this big and heavy a model.

The website with info says 68 oz or 1930 gms flying weight for the model. So we'd want around 400 to 450 watts for a sporty climb of around 30 seconds to get to 300 to 350 ft. But at 450 watts off a 3S pack the current is 38'ish amps. And that means a full power run time from the 850mah of 0.85/38 x 60min/hr= only 1.4 minutes or a bit less of full throttle run time to LVC. That's pretty shy even for only one climb up to altitude if not flying in a contest. I'd suggest that for sport flying where you want to climb up two or three times or catch a thermal on the first climb and don't want to change the battery after landing from the one climb that a 1500 to 2200 might be a nicer option. 2200 is likely overkill but I think a good 1500mah pack would be a nice "three climb and still soar for an hour" option.

Another motor option which is in stock is THIS SUPPO MOTOR OPTION . The Dr Kiwi notes in the link on that page suggests a 12x6, 12x7 or 12x8 might fit with this motor nicely for what you're doing. Or their LEOPARD LC3536-8T looks like a similar weight and performance on a 12x6 or 12x7.
Old 03-09-2021, 05:13 AM
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speedracerntrixie
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Bruce, keep in mind that I had stated " the smallest battery that gets the correct CG " I did use the 850mah as an example of what I personally use in my 3.4 meter Supra. I can get 3 climbouts with the 850 but I agree if CG is correct with a 1000 or up to 1500 that would be better for sport flying. The key here is to not sacrifice optimal CG for the sake of run time. Batteries in this size are cheap and it takes less then a minute to change them. I keep 4 batteries for my Supra and can fly all day by cycling them between the sailplane and charger.
Old 03-15-2021, 06:39 PM
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That is true... It's important to keep the proper CG or what's the point of it all?
Old 04-11-2021, 02:56 AM
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All the panel parts are in. And, SWMBO says it is time to get "all that crap" out of the living room and up to the shop for the build.


PanelPreCon.jpg

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