Yak 54 pictures and CG question

[trent collins]

Guys,
I have just finished my new yak 54. Its from CHmodel in china. Ive also got a Katana and the Pitts S12 from them, best quality ARF kits Ive ever had. Anyhow here's my latest model, a 90" Yak 54 with a 3mm 53cc up front.

Now it didnt come with any instructions so the CG is ????? I balanced it with the C.G on the wing joiner, seemed reasonable to me. Where should a yak 54 balance? Ive had 2 test flights and it seemed pretty close, inverted required only a tiny amount of down elevator however flat spins were not existant at all (confusing) even with 45 degree throws.

I'll take some chord measurements tomorrow and the wing joiner position but where do you think it should balance as a % of chord (most info Ive found gives distance measurements not % measurements that I can directly translate).

My favourite part of the whole model is the aluminium cowl vents, a very cool feature indeed.

[3ddd]

i would think it will be around the 30% mark.25 to 30 is pretty safe on any plane.but your flight report sounds like you nailed it within 1/4 inch or so,i would leave it alone

[Greyhoundman]

Looks nice, do you know what the RTF weight is, and is it really a true 90 inch wingspan?

[trent collins]

The weight is 9.8kg dry. I have two 20oz tanks in it (one for smoke). I think its a little heavy for the 53cc engine, maybe a 75cc would be better. The Katana was 80" and weighed 7.5kg and pulled out of the hover much faster (obviously). Yes its a true 90", I measured it myself to work out a scale pilot size, so its definately 90".