A report is due within 12 months but this will not be possible according to investigators
A final report into the Rescue 116 crash which claimed the lives of four coastguard members will not be available ahead of the first anniversary of the tragedy.
The four crew members of the R116 - Captain Dara Fitzpatrick, Captain Mark Duffy, winch operator Paul Ormsby and winchman Ciarán Smith - died in the tragedy at Blackrock, Co Mayo on March 14.
In a statement the Air Accident Investigation Unit (AAIU) said investigators are "still in the process of gathering factual and background information and is making steady progress".
Under legislation a report must be completed in 12 months of the date of the accident - or in the event that is not possible an interim statement on the progress of the investigation must be published.
The AAIU said it is "endeavouring to issue this interim statement before the anniversary; however, it is not possible to say at this time when the interim statement will be published".
Last year a preliminary investigation into the downed Coastguard helicopter revealed the vehicle 'pitched up rapidly' in its final seconds.
The report also revealed that the helicopter's on board warning system did not have data related to Blackrock island.
An obstacle data base on their system did not list the lighthouse on Blackrock, and the terrain database did not have information on the terrain on the island.
Audio data revealed Captain Dara Fitzpatrick and co-pilot Mark Duffy had discussed earlier in the flight that it had been a long time since either had visited the island.
It showed that the helicopter was in stable level flight at 200 feet on a track towards Blackrock in the moments before impact.
The warning system provided a callout of “ALTITUDE, ALTITUDE” 26 seconds prior to the initial impact.
Captain Dara Fitzpatrick identified the reason for the alert as a small island below the helicopter which she said was “just a small little island…”.
At the time of the aural alert FDR data placed the Helicopter in the vicinity of an outcrop of two rocks, Carrickduff and Carrickad, which are located approximately 0.65 nm to the west of the Blackrock.
In the final seconds, the helicopter pitched up rapidly, impacted with terrain at the western end of Blackrock and 'departed from controlled flight', the report states.