My condoleances to the family and relatives.
This accident reminds me 20 years ago, when an Alouette 2 lost its main rotor while on final. Inquiry reveals that the accident was caused by a human error who used the wrong nut to secure the rotor hub on the rotor mast - The Al 2 and 3 rotor hub to mast attachment were using similar but not identical nut.
D0