The S-76 was doing 145 knots, this one was doing zero knots.
Ooh la! la! Steady on!
Actually, we believe it was transiting to base so probably something like 120Kts at the "occurrence" I expect. It clearly arrived with a considerable vertical velocity too - maybe half of that, plus a fair bit of horizontal before a all that smashed timber stopped it. To achieve damage like that? How about 6000fpm (60Kts ) down and 30 - 60 forward? That's my guess.
A herring gull in the face at 120Kt would easily incapacitate the pilot totally, perhaps doubled over the cyclic pushing it forward and the lever down, or perhaps blinded. The rest I leave to your imagination, but it seems to fit everything we know so far which is more than can be said of most of the theories here.
Highly unlikely the result of an auto or an auto gone wrong, (simply cos its a twin) I can't believe there was
any control available
at all from that arrival so the sort of event described by the AAC chap above describes the behaviour of the airframe but how would an operational Ec130 ever get there?
A fenestron failure in the cruise is surely no more than a nasty surprise at the time as the fin is designed to unload the fan at that speed (Speaking from Gaz experience only) but correct me if I'm wrong.
Unless anyone thinks they were in a hover or at very slow speed at the time (and I haven't seen any suggestion to this effect at all) fenestron and autorotation just don't add up.
They wouldn't risk lifting it via a damaged MGB.
Fuel starvation falls into the auto argument, and in any case is too far fetched for tech/piloting reasons to be credible.
Suspicion of uncontained engine failure would result in fleet grounding and is reasonably easy to check for in situ.
All else I can see is some big and unexpected hydraulics/control failure (but then lifting via m/r head and grounding order arguments apply)
This leaves sabotage/interference or anything else that is so unlikely that no one's yet seriously considered it.
We'll know soon enough.