Optimum ArduCopter motor shaft to motor shaft distance?

[Bill Sanford]

First, what is the span or distance from motor shaft to motor shaft on the shipping ArduCopter?

 

Second, is it better for stability to reduce the span, or increase the span.

 

I understand that yaw control is better with less span,

 

Thoughts?

[Sebastian Gralla]

http://code.google.com/p/arducopter/wiki/ArduCopter_QuadIntroduction

stability is the same on big and small quads (because you change the PID according to it's size)

small quads may have more agillity

bigger quads may can fly more smoothly

 

the exception proves the rule

[Jani Hirvinen]

Exact distances for official ArduCopters are 60cm Shaft-to-Shaft with longer 28cm arms and 46.5cm S-t-S with shorter 21.5cm arms.

 

Empty weight for 60cm ArduCopter without receiver or battery is 775gr. Receivers are usually 12-20gr each. Batteries (usable) starting from 150-180gr and up.

 

 

[Bill Sanford]

Thank you!