[niterdr]

With all of the wonderful new Brushless motors available today how do you ever decide which one to use? I have just gotten back into RC after a brief time away and I guess I missed the intro and fundamental information about the technology. Now there are so many brands and models to choose from that it is confusing to an ol' fart like me. Life was simple when you picked an engine according to the size of the aircraft or the instructions in the kit, now with electrics we have Wattage, Windings, Outrunners and geared Brushless power systems, not to mention Brushed motors. Dang ya blink and new technology just leaves ya in the dust!

Is there a calculator or a guide written to help a newbe to the world of Brushless with the selection or dodo we just go by what the Hobby Shop recommends? Are there any web sites that can help with information?

I have just received some plans for a small (36" Wing Span) twin boom pusher designed for an old pre-nitro gasoline engine and would love to update it to brushless RC.

Cheers,
Alex

[matteo]

www.rcgroups.com has alot of info on motor selection, one of the better electric sites. But if you give a rough estamite im sure that people here can help you out. If its a light 20-30oz plane i would go with 2 axi 2208/26 or equivelent and thats really good power. OR a custom CDR double would be good also.

oh and welcome to rcc

[monty_11]

http://brantuas.com/ezcalc/dma1.asp is a good site for helping to determine the size of motor you need. Generally speaking you want around 75W output power per pound of model for good 3D performance. Most motor specs will give the maximum Amperage or Wattage they are rated for.

Peter.

[Terry Gauvin]

75 Watts per pound will not give good 3D. If you search the net you will find vaiations on this"rule of thumb" performance estimator but hey are all very similar;

Performance Level (Watts per pound Performance Potential)

< 50 watts per pound Unable to rise off ground

50 to 60 watts per pound Can rise off ground and perform simple aerobatics

60-75 watts per pound Easily loops from level flight. More impressive aerobatic performance.

75-100 watts per pound "Fighter"-like performance. Aggressive climbs

100-150 watts per pound Extended vertical runs. Unlimited aerobatics

> 150 watts per pound Wings are unnecessary

[monty_11]

You are right... sorry about that . ..... what I meant to say is 75W/lb would give good aerobatics - not 3D. Definitely over 100W/lb would be needed for good 3D.

Peter.

[niterdr]

The plane will probably weigh in around 1 1/2 Lbs fully loaded and being that it is a semi scale I think I will keep it at the 75 watts per pound to start.
Thanks for the info guys!

Alex