Gents,

thanks for your input.

As far as the motor goes, this will be a bit of an experiment. You'll notice that this motor has the dimensions of an inrunner (long and narrow) which was ideal for the Pico. In the spirit of keeping things simple, I also wanted to be able to use the hardware that came with the motor for mounting purposes - a standard FW mount without having to go to separate mounts or a nose ring mount. 15 size models seem to be the turning point for being able to switch from an inrunner (1/2A) to an outrunner.

Were this model glow powered, it would probably spin either a 7" or 8"prop (10 or 15 size engine) so I looked for a motor that would do something similar on 3s. Based on electric calculations, this motor has maximum efficiency on an APC 7x4SF prop and starts pulling amps (~22A) on a CAM7x6, APC 8x3.8SF, GWS 8x4.3 and CAM 8x6F.

On an APC 8x6E it drops to 92.5% etamax but hits close to 28A and 308W (nominal). The APC 8x6 should spin at ~11,250 rpm which keeps the turns at a reasonable figure for eventual folding props. The equivalent APC 8x6SF loads up the motor a little more to an almost even 30A and 330W @ ~10,900 rpm. Based on Andy's experience, I understand that the model should fly nicely in the 200-250W range (1/3 hp).

With that in mind, it should be doable to spin an 8" prop and perhaps even an 8" folding prop depending on how light Ican keep the model. An 8" prop seems like the natural choice for the Pico (at least to my mind).

Finally, I learned that it is possible to also use helicopter wound outrunners with KV ratings in the 2000+. These motors would spin, expectedly, 5"or 6" props in the realm of 1/2A rpm's but that would limit the options of folding props and would produce noise levels higher than desired.

We'll see how it goes.

David.