The top three finishers from each of the heats advanced directly to the semifinals.
Perri and Diba were disqualified for underweight boats after their heats, but the decision was reversed when judges announced that the super sensitive electronic scales had responded to a change in atmospheric pressure.
Raced on July 31, the top three finishers from each of the three semifinals advanced to the final.
Helm, the youngest competitor of the event, was fifth at the 250 meter mark, then made his move at the last quarter of the race.
Passing Csapó, he shouted for joy as he crossed the finish line in victory.