Well I dono. Final answer.
But - 31.5" used to be the standard 60 class X-Cell boom. When 60s got stretched to .90s the standard tail boom become 33". This was required to accommodate 700+ mm main blades and 105+ mm tail blades. All my 90 class X-Cells have 33" booms.
It wouldn't supersize me at all if X-Cell used the shorter 31.5" boom on 50 class heli. After all, latest generation 50 class helis often have 55 or 60 engines in them and they have more in common with the older 60 class heli than the older 50 class heli. (50 heli engines used to be 46s.) I would be quite suprised to see a 33" boom on an X-Cell 50.
Again, someone will give you a better answer.
Part number 128-140. In stock. 10 bucks.
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