The family of an Irish Coast Guard member who has been missing for almost three weeks have described the tragedy as a "living nightmare".
Orla Smith, sister of missing winch operator Ciaran Smith, yesterday made an emotional appeal to local fishermen for help in bringing him home.
Rescue 116 crewmen Ciaran (38) and Paul Ormsby (53) have not been located since their helicopter collided with Blackrock Island off the Co Mayo coast in the early hours of March 14.
It was hoped the coast guard members would be found in or near the wreckage of the Sikorsky S-92 helicopter, but efforts to locate the two missing men have so far proved unsuccessful.
Ms Smith said the kindness and generosity shown by locals and people across the country has helped her family through the terrible tragedy.
She also praised the efforts of rescue workers and investigators, while appealing for local fishermen to help bring her brother and his colleague home.
"It is a living nightmare for all of us," she said.
"We're doing our best to keep going, to stay as strong as possible and to stay as positive as we can.
"But it is tough - it is really, really tough. We need those boys home now. We really do.
"My parents need them home, my sister-in-law needs him home, my nieces need him home. They have to come home now.
"We're asking all fishing vessels, big and small, from Achill Island to Aran Mor.
"We are appealing to them to please come to help us now. We need them, we need their knowledge and we need them in the ongoing efforts to find Ciaran and Paul.
"We need them and we need their help. We want them to go out and look in a coordinated fashion.
"The RNLI have agreed to coordinate this. We want them to do it in a safe fashion and we want to try and find Paul and Ciaran.
"If they're in the sea and they're there to be found, we need to use the fishermen's knowledge to try and find them."
As the search operation entered its 21st day yesterday, surface and shoreline searches were continuing, but weather conditions again hampered extensive searches for the two missing crewmen.
Ms Smith also said that safety was paramount in further search operations following the loss of four lives.
Her brother was due to celebrate his 39th birthday this Sunday, with his family including his wife Martina and his three young girls aged 12, 10 and seven.
"We do not want anyone to be harmed, injured or God forbid killed in this process," said Ms Smith.
"It is absolutely essential that everyone remains safe and we want it done in a coordinated and safe fashion.
"We want everyone to be kept going and to be kept safe through all of this. We've lost four lives. We don't want anyone else becoming harmed in this. We've had enough now.
"Both families need their men home. The Ormsbys need Paul home and the Smiths need Ciaran home.
"Huge work and huge effort has gone into this search and rescue operation so far," she added.
"Again, we are eternally grateful to those people for putting their lives on hold for everyone who has been lost here.
"We didn't get the result we were hoping for here yesterday.
"We were hopeful that the two guys would be with the wreckage, but they're not. So we need to broaden the scope.
"We need to keep moving forward, keep focused and devise a new plan.
"The guys who have been involved in the rescue operation so far, and are still involved, have been amazing. They've worked nonstop. You can see it in their faces, they're exhausted. They've continued to push to try and find Ciaran and Paul.
"They've had a win already; they found Mark Duffy and brought Dara Fitzpatrick home to her family as well."
Ms Smith was speaking to reporters at the community centre in Eachleim, near Blacksod Lighthouse, which has seen dozens of volunteers feed rescue workers and grieving families with the help of donations from across the country.
Preliminary inspections carried out by the Air Accident Investigation Unit (AAIU) indicate that there were no mechanical anomalies with the Irish Coast Guard helicopter before the fatal collision.
Chief Inspector with the AAIU, Jurgen Whyte, said that the focus will now shift to the operational aspects of the aircraft and journey, adding that the investigation was "a long way" from concluding.
Last week, prayers were said at the funeral of Captain Mark Duffy for the return of the bodies of the two missing coast guard members.
In a tribute at his funeral, read out on her behalf, Capt Duffy's wife Hermione told how he loved his job.
"When Mark came home, he would come in and say, 'Oh Hermione, I love getting home to you and the kids, but I love flying that helicopter'," she said.
"Our charming, handsome, and bashful daddy hero. Guess how much I love you? I love you to the moon and back."