He will now join the crew of a decoy ship: looking like an ordinary fishing schooner, its crew pretending to be civilians, it will actually have a concealed radio to summon the sub chasers as needed.
He will now join the crew of a decoy vessel: resembling an ordinary fishing schooner, its crew pretending to be non-combatants, it will actually have a concealed radio to signal sub chasers as required.