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What size engine would I need for this aicraft? (details and pictures inclosed) Answered

I am building an R/C extra 300 and am about to buy the engine, but im not so sure what to get.
I think I should buy a 30. sized brushless or up engine, by what make should I get. I would like to power it electricly

wingspan= 4.5ft
Lenth with cowling= 42 inches
wieght w/ servos and pushrods but without radio, lipo battery, motor and speed controler. = 1lb 4 oz
width (at largest part) 5 inches.
Servos: 4.5v 1.5kg torque

I would also like to know what speed controler and battey I would need.




You might try here?
I didn't look too hard, but I keep thinking of guys I know who's planes are now largely held together with tape... I guess you'll not be flying that into the ground?


The last thing on my mind is flying it into the ground. I have spend about 2 months so far on this, thats why I havn't published many instructable's recently...
But on the good side im nearly finished, I just need to finish the front of the plane and im waiting for some other bits to get vacuum formed. etc. I will be publishing this as an instructable in 1 to 2 months, Im hoping to get it in the newsletter.



What size glow motor did the plans say to use?  Most electric motors are marked for glow equivalancy.

Was this kit made for glow/electric use?  If not then it's not up to holding the extra weight of the batteries without making provisions for them.

Its not a kit or made from plans. I drew the plans and  made it my self to be electricly powerd. Its going to be an instructable

You did it yourself!  Great for you!

You need about 750 watts of power for that sized plane.

Google "glow to electric conversion" and you'll get several sites that help you decide which engine you put in your plane.  Alot depends on the final weight of the plane.  That will change with the engine/battery combination you decide on.  So you see it's not a cut and dried answer.

What brushless motor would you suggest? I don't know where to start if im looking at 750 watts of power.


750W sounds much more than enough, large wings, slow speed?


It's an acrobatic plane so it needs to be a little over powered.

You're optimistic. But yes, if you want speed and performance you need a lot of power. What sort of LiPo (?) pack do you reckon for that power?