A fresh effort to locate two missing Irish Coast Guard Rescue 116 airmen has been stood down in north Mayo after further intensive sea searches around Blackrock island.
"We have covered everything we aimed to, and a bit more," Supt Tony Healy of Belmullet Garda station said on Tuesday evening as the Irish Lights ship Granuaile prepared to steam south to Galway.
A weather window over the weekend had allowed for settled sea conditions around the crash site at Blackrock island, 13km west of the Mullet peninsula.
It is over four months since the Sikorsky S-92 helicopter collided with the rock, claiming the lives of Capt Dara Fitzpatrick, Capt Mark Duffy and winch team Paul Ormsby and Ciarán Smith.
The bodies of the two winch crew have still not been found, and the new Garda-led search aimed to return to areas where weather and swell had restricted efforts previously.
Without the swell that is a constant around Blackrock for much of the year, the Granuaile was able to deploy the Marine Institute's remotely operated vehicle (ROV) on a 24-hour basis over a period of four days.
Garda Water Unit divers assisted, while a group of 25 Irish Underwater Council-approved club divers searched Duvillaun to the south and the Inishkea islands to the north at the weekend.
The Marine Institute said its team of six ROV operators conducted a "detailed and thorough" search, using the high-definition cameras and lighting system, assisted by a surveyor with its advanced mapping section.
“Previously examined areas were revisited in the calm conditions, and the search was also expanded as terrain would allow to the north and south of Blackrock, and to the east of the crash site,”it said.
Items of debris were located, but there was no sign of the missing crewmen, and the Marine Institute said it wished to extend its sympathies to the families of all the victims of the crash.
A representative of the Air Accident Investigation Unit (AAIU) was on board the Granuaile to provide aviation expertise in case further parts of the aircraft were located.
An AAIU spokesman emphasised that the priority was finding the missing crewmen.
Last week a fishing vessel fitted with a “bespoke “ net had also trawled around the island.
Donegal's Sheephaven Sub Aqua Club, which participated with trained search and recovery divers from Mayo's Granuaile, Galway and Donegal Bay clubs, said that water conditions were "at their optimum" with good visibility, and this allowed for detailed searches of coves, inlets and gullies.
The divers were accommodated and fed by local families in Eachléim and the wider Blacksod peninsula.
Supt Healy said all the information gathered during the past eight days would be assessed. “If evidence turns up again, in the form of debris or whatever, we will pursue that.”.