The family of Capt Dara Fitzpatrick have said the crew of Rescue 116, who were killed when the Irish Coast Guard helicopter crashed in 2017, were "badly let down".
A final report by the Air Accident Investigation Unit (AAIU), published on Friday, found several navigational issues and problems contributed to the crash.
Capt Fitzpatrick, Capt Mark Duffy and winch team Paul Ormsby and Ciarán Smith all died when their Sikorsky S-92 helicopter crashed at Blackrock island, 13km west of Blacksod, Co Mayo, in March 2017.
In a statement, the Fitzpatrick family said “our thoughts today are with the other three families and all who love the four crew who died”.
The AAIU report had highlighted “many failings in the operation of the air-sea rescue service operated by CHC Ireland”, it said.
“We believe that Dara and the other crew members of the Rescue 116 were badly let down by the operator CHC not providing them with the safe operating procedures and training that they were entitled to expect.”
The family said the crews often operated in “extreme weather conditions” and at night, while they might be fatigued.
The statement called for recommended changes and reforms to be implemented “urgently”. The air rescue service should “in future pay attention to the feedback they get from flight crew as to any inadequacies and hazards in the operation, so that such an accident will never happen again”, the family said.
CHC Ireland welcomed the final report and said it would implement all recommendations for safety reforms.
Rob Tatten, general operations manager, expressed “deepest sympathy” to the families and friends of the four crew who died in the “terrible tragedy”.
“We continue to honour the memories of Ciarán, Dara, Mark and Paul. They will never be forgotten,” he said.
The Department of Transport has said it fully accepts the recommendations of the report, and “will continue to evaluate the findings of the report in the coming weeks”.
Minister for Transport Eamon Ryan described the crash as a “tragic accident that claimed the lives of four individuals who were dedicated to saving the lives of others”.
The Irish Air Line Pilots’ Association (Ialpa) said the report showed the loss of life was “preventable”, and highlighted “regulatory and systemic issues” that put the crew in danger.
The statement said the helicopter crew were “exemplary in the performance of their assigned task” while operating “offshore in challenging conditions”.