A major search operation has failed to locate any sign of two men whose boat has been missing off South Australia's Eyre Peninsula since last week.
Derek Robinson and Tony Higgins left Coffin Bay bound for Goolwa in a wooden-hulled fishing boat named Margrel last Thursday.
The men, from Fleurieu Peninsula, made contact with a friend saying they were having engine trouble on Friday and were going to divert to Kangaroo Island.
The men have not been heard from since.
Eyre and Western Local Service Area Superintendent Paul Bahr said despite the search area expanding, there had been no sign of the men or their boat.
"There has been no sign of any debris, we still don't have a distress signal," Superintendent Bahr said.
"Every minute we go without hearing from them increases the level of concern."
He said the aerial search would be reviewed before determining the way forward.
Aircraft from Perth, Essendon and Edinburgh air bases have covered an area larger than Tasmania in the search south and east of Port Lincoln.
The search has been widened from an initial strip from Eyre Peninsula tracking to Victor Harbor, to now extend from West of Coffin Bay to south of Kangaroo Island, following strong northerly winds yesterday.
It is understood the boat underwent maintenance before leaving Coffin Bay.
SA Police have asked anyone with more information on the journey plan or who may have seen the boat to contact them on 131 444.
