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My new wing project. I’ve got foam parts for two sub250g spec racing wings with 59cm wingspan. Got curious to make one as a long-range wing with submerged electronics and integrated 2S Li-Ion cells.

Grabbed electronics nearby and weighted that roughly. It’s going to be light wing.

As a racing wing, it has symmetric airfoil profile, so it would not be as efficient as cruising wing like Nano Goblin. But still, it’s interesting to try how it will feel. So first I need to calculate it’s CoG (Center of Gravity) before spreading the electronics. I use cgCalc – Center of Gravitiy (CG) Calculator that allows you to define the wing’s shape precisely. The result is 111-118mm from the tip.

Next step is to spread stuff around and keep CoG in place. Here I use Flying wing CG calculator, but it doesn’t give a possibility to draw exact shape so I changed the length of the root chord to get the CoG in the area measured above. I set it in 117mm. Then I measured the weights and dimensions of all parts and started playing with positions. Every time I move or add new part red cross shows the current CoM (Centre of mass). At the moment positions look like this. Motor and servos will be installed first, then other electronics. Li-Ion cells will be installed as the last part, as their position will affect on CoM hugely. So with them, I cold adjust CoM better to get into CoG.

2020-08-10

Slow progress. But servos are installed!