Four months after the Rescue 116 disaster off Black Rock fresh questions have been raised about when the company responsible for an onboard warning system were first alerted to shortcomings in the system,
RTÉ's Prime Time have revealed that a pilot had previously flagged the absence of Black Rock from the onboard warning system four years ago.
The programme revealed that the pilot who carried out test flights on the new safety systems reported the lethal danger inherent in the absence of Black Rock but the error was not corrected at that time.
The Coast Guard’s Search and Rescue service is run by a private operator, CHC Ireland, which is a subsidiary of global helicopter services provider based in Canada.
The company won a 10 year €500 million contract to provide the service in 2012.
All of the Coast Guard’s Search and Rescue helicopters have been equipped with an Enhanced Ground Proximity Warning System since 2013.
The safety system is designed to warn pilots to take corrective action to avoid a collision if they get too close to terrain or a known obstacle but the system can only work if its database has a complete picture of the terrain and obstacles on a flight path.
Because Black Rock Island was not in the system, the pilots flying Rescue 116 did not receive a warning and did not see the island until it was too late.
All four on board lost their lives while out on a rescue mission.
Nine days after the crash, it was discovered that the data relating to the location of Skellig Michael on the safety system was also dangerously inaccurate.
RTÉ Prime Time have revealed there was numerous emails sent between Sligo base Coast Guard pilots and a senior CHC manager regarding Black Rock Island in 2013.
The emails highlighted the absence of Black Rock and stated it was a safety concern as the 282 foot island was on the route approved by the company for approaching the refuelling base at Blacksod Bay from the South.
According to a source quoted in the RTÉ Prime Time programme, Coast Guard personnel were told at a meeting in April, six weeks after the Rescue 116 crash, that management was trying to establish if this information had been passed on to the company that supplied the database for their system.
The company responsible for supplying the database, Honeywell, told Prime Time that they could not comment as it was an ongoing investigation.
Prime Time also revealed that search and rescue pilots had complained that the system was alerting them to avoid an obstacle that did not exist.
A spokesperson for CHC told RTÉ that the company is prevented from responding to their queries under international protocols governing air accident investigations.
The spokesperson said the company "has multiple systems and programmes that encourage employees to report any safety concerns...Our focus remains on supporting the families and friends of all of those affected by this accident."
The Irish Aviation Authority’s State Safety Plan has said that the Authority provides terrain and obstacle data for use by database suppliers.
It told RTÉ that: "Black Rock Island was not shown as it does not constitute an obstacle under ICAO (International Civil Aviation Organisation) Standards".
The Authority said it has no record that it was advised that Black Rock Island was not in the Coast Guard’s EGPWS system.
They also confirmed that it only learned that Skellig Michael was inaccurately depicted on their official maps nine days after the Rescue 116 crash.
The official Aviation Authority aeronautical map had previously indicated that Skellig Michael was just 174 feet.
This was the height of the lighthouse, not the island's highest point.
The Authority alerted pilots immediately and issued a new map last month which increased Skellig Michael to its actual height of 712ft.
The Irish Airline Pilots Association refused to comment specifically on the ongoing investigation stating it would be inappropriate.
However, the Authority said: "Separately from the Rescue 116 accident and its ongoing Annex 13 investigation, the Irish Air Line Pilots' Association has raised concerns with successive Ministers for Transport on the effectiveness of the Irish Aviation Authority in fulfilling its Safety Regulatory and Oversight obligations."
It said the concerns raised by IALPA with successive Ministers for Transport are germane to the questions and issues raised in the RTÉ Prime time report.
The Aviation Authority rejected this.
It said: "We note IALPA’s view. However, this is not shared by anybody in the industry, specifically the international organisations that continuously audit Ireland’s safety oversight regime. The IAA is one of Europe’s most respected aviation bodies and is clearly recognised as a leader in its field."