Jetscream 32,
You point out some valid points regarding the 'Hasell' checks. How many of us when doing our clearing turns automatically look down and call clear and neglect to also look up?! Perhaps a few of us?!
I am sure the AAIB will determine the most likely cause of this dreadful accident. Accidents do happen sadly.
Sincere condolences to all those who sadly died in this incident.
Big Sand.