Parnaiocas,
well done for the AW139 analysis, simply because few non-AW users knows about S/N logic for this particular rotorcraft line.
However,
if you had investigated a little bit more, you would know that:
- (new) fuselages are not manufactured separately, but they are rawly prepared in Poland and reworked in an Italian facility, while (new) blades are completely manufactured in Italy - while repair stations are located around the world.
- both in Vergiate and in Philadelphia final arrangements and test-flights are performed. If you look at the no. of helos released from Vergiate and Philly, you will notice that we are absolutely not around 50%/50%, but 80%/20%.
Therefore, in case of a mechanical/structural failure, assessing the historical data, I'd rather not look only at where the helicopter has been passed through a completion centre, but the whole history of a certain S/N and the components subject of a failure.
The first investigation criteria is to face the incident/accident scenario without pre-concepts, cleaning our mind from any possible mis-concept: in case of dynamic failure of a component, a manufacturer has to patch it, and patch it quickly,
but the stressing factors of an accident are multiple and have to be deeply assessed.
Providing uncomplete or misleading data creates only white noise.