The sunken wreck of the MV Louisa is to be raised as part of an investigation by the Marine Accident Investigation Branch (MAIB).
The shellfish boat sank off the coast of Mingulay as it lay at anchor in calm seas on April 9 with three of the four man crew tragically losing their lives.
Investigators are keen to probe why the vessel became flooded with water and if the boat’s automatic alarm system sounded as it should when a leak is detected.
They also want to find out why the Louisa’s liferaft failed to release and then did not inflate.
South Harris father-of-two, Chris Morrison, 27, and Martin Johnstone, 29, from Caithness died in the tragedy, Skipper Paul Alliston remains missing.
The sole survivor is Lachlan Armstrong, 27, from Stornoway, who managed to swim ashore to rocks.
The boat is lying in about 10 metres of water with its mast visible at low water.
A spokesperson for the MAIB told the BBC: “We have made a decision to raise the wreck and will do so when there is a suitable weather window.
“The aim of our investigation is to establish why the fishing vessel Louisa sank and why lives were lost.
“A full and detailed report will be published at the end of our investigation.
“If we identify any safety issues during the investigation that require immediate action, the Chief Inspector of Marine Accidents will issue a safety bulletin or make recommendations as appropriate.”