David Marr, 45, was skipper of the fishing boat Vertrouwen just after midnight on August 6, 2017, when it passed extremely close to the James 2, which was swamped by waves and sank.
Romanians Mircea ‘Mitch’ Ilie, 43, from Brighton, his brother-in-law Irinel Popovici, 41, and Traian Dumitrache, 51, all drowned.
Elvis Cojocariu, who was 45 at the time, was the only survivor after being picked up from the water five hours after the sinking.
He told Lewes Crown Court yesterday (March 12) that they saw the Vertrouwen from about a kilometre away and had been signalling ‘like mad’ before the collision.
Despite their warnings, the Vertrouwen carried on at the same speed and swamped the boat with waves.
Mr Cojocariu told the court, according to the Crown Prosecution Service, that he had a clear view of the deck as the boat passed and could not see anyone on there.
The prosecution’s Libby Clark said: “It was our case that David Marr had not been paying sufficient attention, if any, when he was on watch.
“Had he done so, he would have seen the men on the James 2 as he headed close to them, who were frantically signalling to him in a bid to avert disaster.
“Instead of constantly checking to ensure he knew what was out there, it appears he was doing other things and, even after his actions caused the James 2 to sink, he continued to sail on, oblivious to the fact that three men were about to die as a result of his not keeping a proper look out.
“The evidence showed that he would have been able to see the lights on the boat for six minutes before the near miss, yet he continued to sail directly towards the boat with tragic consequences.
“It was not unusual for small fishing boats, like the James 2, to be in this area and the defendant should have been alert to that and the fact that small vessels may not be detected by radar at an adequate stage.
“David Marr should have been using every means available to him, as required by maritime regulations, to establish what, if anything, might be in the sea ahead of or around the ship.”
According to the CPS, during the trial the jury heard expert evidence from a master mariner, who explained a proper lookout on a ship requires the watchkeeper to give full attention to their task and to be continually scanning ahead and around the vessel.
They also need to be mindful that smaller vessels may only be detectable at a short range, the mariner said, and that marine guidelines state two people should always be on watch during the hours of darkness.
Investigations showed that both the main and back-up radars of the Vertrouwen were replaced on August 3, 2017, just days before the incident happened, and checks were made to ensure they were working.
The first mate also confirmed that the radar equipment was working correctly when he took over the shift just hours after the incident.
Evidence also showed that the defendant appeared to be using the ship’s laptop computer around the time of the incident and was also sending WhatApp messages to a friend, the CPS said.
David Marr was convicted of failing to maintain a proper lookout, contrary to regulations 4 and 6 of the Merchant Shipping (Distress Signals and Prevention of Collisions Regulations) 1996.
He was jailed for one year.