Not helicopter related but the classic 'distraction causing an accident' accident occurred on December 29, 1972 just West of Miami over the Everglades. An Eastern Airlines Lockheed L1011 on approach for landing. One of the Gear Down lights fails to illuminate. The crew of three becomes so preoccupied with what is likely a burnt out lightbulb that they allow the aircraft to descend into the swamp, resulting in 99 fatalities.