The crew member recovered after this morning's helicopter crash has died, the Irish Coast Guard has confirmed.
The deceased Coastguard member has been named as Captain Dara Fitzpatrick who was a senior pilot with the coastguard with 20 years experience. She had spent time working with R117 in Waterford in recent years.
At a briefing at Blacksod lighthouse the Search and Rescue operations manager with the Irish Coastguard, Gerard O'Flynn, said the news was a hammer blow.
Captain Fitzpatrick had been transferred to Mayo University Hospital after being found in a critical condition.
She was a well known member of the Coast Guard service and was also involved in several water safety campaigns.
Dara was one of very few female civilian pilots worldwide, and was featured in the RTE series Rescue 117 filmed at Waterford helicopter base.
The other three crew members have yet to be recovered.
Meanwhile, the Garda Water Unit has arrived at the pier beside Blacksod Lighthouse to assist the search.
Five Coast Guard jeeps are also at the scene.
A Department of Transport representative said: "All possible assets have been deployed to the scene".
The Taoiseach Enda Kenny who is on a visit to the United States is being briefed on the mission in Blacksod.
In a statement he says his thoughts are with the families of the crew and the emergency services working in the area.
