A Canadian Coast Guard crew was monitoring the tow of the sealing boat L'Acadien II on the night it capsized, killing four fishermen, says a draft report by the Transportation Safety Board.

Four fishermen from the Magdalen Islands died shortly after midnight on March 29 when their disabled ship overturned during what was supposed to be a routine trip to shore with the coast guard.

Don Eaves, who led a team of 10 that just completed a draft report into the sinking, told CBC News on Thursday that, contrary to eyewitness testimony following the sinking, there was someone on deck supervising the tow.

"Based on anecdotal statements and electronic data, we are convinced that there was a watch," said Eaves.

The report has not yet been released, and there are many details Eaves won't share, such as how fast the coast guard ship was moving when it towed the L'Acadien II, or how the captain reacted when it capsized.

"Unfortunately, I can't share that with you," he said.

Wayne Dickson said he would contest any part of the report that said there was a coast guard watch. (CBC)Wayne Dickson, captain of a ship that was sailing behind the L'Acadien II, said he remembers every detail of that night.

Speaking for those who died

"As far as I can say, we're the only guys, the witnesses that saw what happened. We have to speak for [the four men who died,]" said Dickson.

While he has not yet had a chance to read the report, Dickson is taking issue with the details that have been released. He said he'll contest any part of the report that states there was someone on deck of the coast guard ship when L'Acadien II sank into the ocean.

He is also questioning the usefulness of two simulations of the accident that Transportation Safety Board investigators observed in July, saying it would be impossible to recreate the conditions of that night.

"The boat was in the water and ice, continuously; we were sailing through broken-up ice," he said.

"The icebreaker was parting it, and there were pieces going here and pieces going there, and on both sides of us was still solid ice."

Dickson says the Coast Guard icebreaker pulled the rudderless L'Acadien II over an ice floe, and that's what caused it to lose stability.

The draft report has been released to specialists, experts and witnesses for their comments.