The probable cause of the Manx2 plane crash at Cork Airport in February 2011 that killed six people was a "loss of control" during an aborted landing, a report has found.
There were 12 people on board the flight from Belfast, which crashed in fog after failing to land on its third attempt.
The Irish Air Accident Investigation Unit report described poor visibility and a tired crew as "significant" and says the crew continued with the third descent without "adequate visual reference being acquired".
A prohibited manoeuvre led to a rapid deceleration and the aircraft to roll - a difference in power between the two engines may have made this situation worse.
The crew pairing is described as "inappropriate" and they both went on duty without their prescribed rest.
The recently promoted Spanish pilot was inadequately trained in the command role and the English co-pilot had just joined, his duties were changed and his final training was incomplete.
The report also questions the whole Manx2 operation.
While Manx2 as ticket seller, had an arrangement with the overall owner to supply aircraft and crew, there was neither a contract nor communications between Manx2 and the Spanish-based flight operator Flightline.
It's also revealed Spanish authorities were unaware the plane was operating in the U.K. and Ireland.
In conclusion, the report says Manx2's commercial model was not in the best interests of passenger safety because of a lack of accountability.