I'm relatively new at all of this, and have question . . . Why do the 'performance' helicopters seem to come with ccpm/eccpm control but the 'lower' end tend to come with the 'regular' style? My raptor 50 v2 uses the 'normal' type (according to my JR 378, that is) but the JR Helis that I've seen seem to prefer the CCPM . . . .

thanks!

Mark F. Sanderson

CCPM/eCCPM/EMS = same thing

Mechanical mixing or electronic mixing are just 2 different ways of accomplishing the same thing. There are advantages and disadvantages to both. Whether a helicopter is a 'performance' helicopter or not has little to do with whether it uses CCPM or mechanical mixing.

Ben

Ben,
What might be those dis/advantages?

Thanks!
Mark

Advantages of CCPM: Fewer parts, less complicated to assemble and repair, distibutes the forces over several servos.
Disadvantages of CCPM: Almost demands very precise servos, very sensetive to proper setup or you end up with interaction between functions (even with proper setup you can have a small amount of interaction).

Advantage of mechanical mixing: Less confusing radio programming, no interaction between controls
Disadvantage of MM: More parts, not much else - mechanical mixing works just fine

Ben

What do you mean by 'interaction'? Does this mean that operating collective could 'accidently' mix in some cyclic in the wrong direction if not perfectly setup - or something to that effect?

Mark F. Sanderson

Yes. Since you have 3 or more servos all controlling the swashplate at the same time if they don't travel at the same speed and/or have exactly the same endpoints - you will get an interaction.

Most new CCPM helis have been designed to reduce this situation, but it still requires careful setup of the servo arms, pushrods, and bellcranks. Using precise servos, like digitals, will also make it easier to set up. Most computer radios have some features to help with this too.

Ben

Go to our club site for some details on mixing types and pros/cons.

www.scotiabladerunners.ca

Go technical, then theory of flight.