Hi Geoffers,
Yes there have been at least an history of a drive shaft failure on a 365N.
A close friend of mine experienced a failure of the output flector (# Thomas Coupling ) at the main gear box output level. The design is the same on the N3.
It happened on a rig take-off .... first heavy vibrations with a loud banging jerking noise, than the armed floats deployed uncommanded (due to combined vibrations and the shocks of the ofset turning shaft still attached to the flector banging against the "mechanical Floor" that triggered the floats relay located just above on the "mechanical floor" )
The pilot, on the very early stage of the take-off managed to turn back to the deck, where he slammed the helicopter down as the flector completely broke.
It is interresting to note that the inflated forward floats almost completely impaired his downward vision to aim at the center of this small helideck.
I can add, that after many thousands hours(#8000) on different versions of 365 and also Gazelle flying not only offshore but also aerial work (long line,sling, movie shooting, picture taking, survey, military etc....) I've never experienced, nor never heard one of my colleagues talk of a so called tail rotor stall or fully developed LTE on these types.
Could it be pure luck after all ?
Last edited by cpt; 14th Mar 2016 at 11:19.
Reason: additional info