A six-man diving unit is on the site of the sunken Tit Bonhomme in Glandore Bay, off west Cork, where it went down on Sunday morning.
It is the first time that the weather and Atlantic swells have eased sufficiently to allow divers to get near the wreck, where search teams are looking for five missing fishermen.
Nets and other debris being washed in and out of the trawler have also posed serious dangers as the search entered its fourth day.
The bodies of skipper Michael Hayes (52) and crewmen Kevin Kershaw (21), Said Mohammed (23), Wael Mohammed (35) and Attea Ahmed Shaban (26) are believed to be on board the sunken trawler.
Navy spokeswoman Lieut Cmdr Roberta O’Brien said a team of six Navy divers and a co-ordinator were taking advantage of the break in the weather.
It is understood an initial 10-minute assessment dive is normally carried out before divers take to the water for a more extensive search. The swell dropped to 0.5m, and the wind shifted direction from southerly to westerly overnight, helping to ease conditions at the wreck site.
Relatives of the missing men have maintained pier-side vigils since the alarm was raised at 6am on Sunday.
The search for the five Tit Bonhomme crewmen was hampered yesterday by strong winds and rough seas, which prevented divers from diving on the wreck near Adam Island at the entrance to Glandore Harbour.
Relatives of the missing men gathered on the pier for a third consecutive day as they waited for news. Mr Hayes is from Helvick Head in Waterford and Mr Kershaw is from Dublin. The other three crewmen are from Egypt.
Relatives of some of the missing men became very frustrated. It is understood relatives of some of the Egyptian men brought in a commercial Egyptian diver to examine the vessel, but he was dissuaded from going down as it was too dangerous.
Fishermen yesterday reported the aluminium wheelhouse of the 21m steel-hulled boat had been virtually demolished by the repeated battering against the rocks it received since sinking at about 6am on Sunday morning.
It is understood the sole survivor, Abdul Mohammed (43), also from Egypt, was swept out the door of the wheelhouse and, despite suffering a broken collarbone, swam almost half a mile to shore, where he was rescued by Toe Head Irish Coast Guard boat.
Searchers hope the remains of the five men may be on board the sunken vessel, though they are puzzled as to why no bodies have been found on the surface if the men had the chance to put on life jackets with flotation devices, as some reports have suggested.
Baltimore and Courtmasherry RNLI Lifeboats yesterday continued a search with local trawlers. Smaller craft crewed by locals searched caves and inlets in the harbour where debris from the vessel has been found.
Bishop of Cork and Ross Dr John Buckley led locals in a multidenominational prayer service on the pier side last night and paid tribute to the local community for their help and support over the past three days.
Earlier yesterday, a Muslim prayer service was lead by religious leader Aymen Essa.
Cork-based Muslim religious leader Morad Gharib said the Egyptian community was deeply moved by the level of support offered locally.
Additional reporting PA