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        Discussion 049 Cox Cessna Skylane

#1 haybale22 Sep 27, 2012 09:41 AM

049 Cox Cessna Skylane
 
I was given a never been flown before 049 Cox Cessna Skylane from the late 1980s. Still had the starter pack with the can of fuel, starter battery and the 2 channel radio. I have never had a glow style plane before but I got a new battery and tried starting it last night. I managed to get it to fire up a few times but never got it to run for very long. Obviously a bit of a learning curve trying to get the right needle valve setting etc. while not taking off my finger ;)
If I get it running better I would like to try to fly it however I heard that it can be a challenge to fly with no throttle control.
I like the idea of keeping it original but also have thought about converting it to electric. I have seen a few threads on this but am wondering what the general thought is on this. Is it worth doing and if so what would be a good power combo for this model?

#2 Majortomski Sep 27, 2012 10:06 AM

The fly just great w/o throttle. You just have to be up high when the fuel runs out. Start with the needle valve open three turns then turn it in to peak the engine. I wouldn't use the sanwa radio if u are used to a radio with aileron and elevator one stick. You'll probably bend the right stik trying to add up elevator

#3 haybale22 Sep 27, 2012 12:37 PM

Hopefully the weather will cooperate and I will get a chance to take it up this weekend. Took me awhile to get it started the other night and it really surprised me when it finally did fire up. I am sure that the look on my face was pretty funny. The plane had just been sitting in my friends garage since he bought it. He put it together but never fired it up or flew it for whatever reason.

#4 Majortomski Sep 27, 2012 12:45 PM

check the firewall after a couple of flights they tended to vibrate themselves out of the foam. If it does just epoxie it back in

#5 haybale22 Sep 28, 2012 07:20 AM

Thanks for the tip. If I did want to convert it to electric, what would be a good power combo to use?
I have a GWS EPS-350C sitting around. Would that work? Not sure how I would mount that though.

#6 Majortomski Sep 28, 2012 01:47 PM

I have know idea, the last time I flew one was in the 80's and that was on the cox engine.

Best of luck

#7 super kupfer Sep 29, 2012 07:44 PM

Cox engines start a lot easier if you prime it, keep priming it over and over, it should start easier.
They get a lot easier to start when they are warm.

The Cox .49 Black Widow was my first engine when I was a kid.

#8 groundfx Oct 05, 2012 11:25 PM

I'd fly it as glow if you have a place to do that. Keep simple, simple.

However should you decide to convert it, here's some thoughts...

A Cox QRC .049 turns a 6x3 prop at about 14000 rpm for a typical engine. This is about 60 watts to the prop and a pitch speed of about 40 miles per hour.

For reference, these props and RPM's all use the same amount of power and give the same amount of thrust and pitch speed.
Code:

dia        pit        rpm
6        3        14000
7        4        10500
8        5        8100
9        7        6200
10        8        5100

Assuming a 75% efficient brushless motor, that means you need about a 80 watt motor. Using the 3 watts per gram rule, you need at least a 27 gram motor to do this. Any old generic 2208 or 2212 sized motor can handle this with ease. To avoid balancing problems, I'd probably try a 2212-10 (1400 Kv) motor on 800 to 1300mah 2S battery with a 8x6 prop. Should you want more power, switch to 3S and a 7x4 prop.

However, before picking motor and battery, I'd mock it up with weights to ensure it will balance on the CG correctly. Pick motor and battery sizes so you don't need to add any weight to balance.


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