On October 14, 1996, at 0720 central daylight time, a Bell 206L-3 helicopter, N21497, owned and operated by Petroleum Helicopters, Inc., was substantially damaged during a precautionary landing near Venice, Louisiana. Visual meteorological conditions prevailed for the Title 14 CFR Part 135 air taxi flight. The commercial pilot and three passengers were not injured. A company flight plan was filed. The flight was originating from the Shell Heliport at the time of the accident. According to the pilot, the helicopter was approximately 50 feet AGL during takeoff when he heard a "big pop and the helicopter was shaky and noisy." He initiated a "deceleration to land "due to the wires in front of the helicopter. During the landing, a 2-foot section of the tailboom which included the vertical fin and tail rotor gearbox, separated from the tailboom. Throughout the forced landing he had tail rotor pedal control. The passengers reported that on takeoff they heard a noise like a "backfire," and then the helicopter began to shake. According to the operator, the damage to the helicopter resulted when "a main rotor blade flexed down and severed the tailboom." An examination of the engine by the operator revealed that frogs had been ingested.