An independent review recommended by the Air Accident Investigation Unit in its interim statement into the Rescue 116 crash off the Co Mayo coast is to be carried out.

Minister for Transport Shane Ross said the review will be carried out by an external party and it will take account of the previous and ongoing work cited in the AAIU report in relation to the search and rescue aviation oversight.

In a statement, the minister said the aim of this review will be to ensure that our arrangements in this regard are sufficiently robust and measure up to international best practice models.

The Air Accident Investigation Unit published its interim statement on the progress of its inquiry into the crash today.

The company that operates Coast Guard rescue helicopters was told to conduct a full review of its safety management systems by the agency.

The AAIU says it has concerns about the efficacy of the systems operated by CHC and has recommended that they be fully analysed.

The AAIU says it is examining all aspects of the fatal flight, including the initial tasking of the crew on the night in question.

A second recommendation has been made in relation to the data recorders used on the helicopter.

This comes after concerns that a software issue could cause some information regarding the flight to go unrecorded.

The AAIU says it has all the necessary information it needs regarding the R116 flight but that its investigations have revealed a possible glitch that needs to be addressed. 

The report also recommends that the Minister for Transport should carry out a thorough review of all Search and Rescue (SAR) aviation operations to ensure there are appropriate processes, resources and personnel in place to provide effective, continuous and comprehensive oversight of all aspects of these operations.

The statement outlines the extent of the inquiry to date, provides an update on responses to earlier findings and makes what have been described as "significant safety recommendations". 

Four Coast Guard crew members died with their helicopter crashed into Blackrock Island, in the early hours of 14 March 2017. 

The bodies of Captain Mark Duffy and Captain Dara Fitzpatrick were recovered in the days following the tragedy but those of their colleagues, winch operator Paul Ormsby and winchman Ciarán Smith, remain lost at sea.

It is the second significant update on the course of the investigation, since the inquiry was launched on 14 March last year.

Last April, the AAIU published a preliminary report into the circumstances surrounding the crash.

It contained detail of the final moments on board Rescue 116 and identified problems with navigational equipment used by the crew, as well as issues with safety devices on their life jackets. 

Today’s interim report comes after the AAIU announced in January, that it would not complete its full investigation before the first anniversary of the crash. 

Last Wednesday relatives, friends and colleagues of the four crew members gathered in Blacksod to mark the first anniversary of their deaths. 

The interim report into the crash of the Irish Coast Guard Rescue 116 helicopter off the north Mayo coast last March has recommended a thorough review of all search and rescue aviation operations.