VeeAny, I'm glad that you took that 5 minutes to give it some thought. Thanks. You gave my brain something to work on before it exploded.
The splines at the back to the engine gearbox in a 206 are driven from a shaft in the freewheel unit not the engine.
So true! For those that find that a little confusing, please see the attached drawing. The freewheeling unit shaft outer race (#14) is driven by the engine. The inner race shaft (#1) attaches to the main drive shaft and is driven by #14. The spline adapter shaft (#28) leads to the tail rotor.
So, we're in agreement that all the torque goes through the freewheeling unit. What I'm not sure about is that it all goes through the main transmission, counting against the torque limit.
Please note that I'm not saying to exceed any limits! Don't do that. I don't do that. I'm just using that as an example. I should have said 90% instead of using 100%. I was just trying to figure out if the engine torque demanded by the tail rotor goes through.... oh you know.
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