Complex sentence: Raphaël Dinelli's boat capsized and he was rescued by Pete Goss; then, within a few hours of each other, two other boats capsized, and their occupants were rescued by Australian rescue teams.
Split into simpler sentences: Raphaël Dinelli's boat capsized, and he was rescued by Pete Goss. Then, within a few hours of one another, two other boats capsized, with both rescues performed by Australian rescue teams.