The fire began on the 79-foot boat at 10 a.m. while seven members of a marine salvage company were on board. They managed to get out safely by jumping overboard.
"I thought they kicked over the engine at first, but when more and more black smoke started to develop out of it, I knew something wasn't right," said witness Chris Beeson.
The commercial fishing vessel is home-ported in Honolulu and was returning from American Samoa.