From the NTSB web site:
NTSB Identification: MIA04LA132
Nonscheduled 14 CFR Part 135: Air Taxi & Commuter
Accident occurred Wednesday, September 29, 2004 in Gulf of Mexico
Aircraft: Bell 206L, registration: N34CA
Injuries: 3 Uninjured.
This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed.
On September 29, 2004, about 0800 central daylight time, a Bell 206L helicopter, N34CA, registered to and operated by Panther Helicopters Inc., as a Title 14 CFR part 135 on demand air taxi flight, ditched into the Gulf of Mexico. Visual meteorological conditions prevailed, and a company visual flight rules flight plan was filed. The airline transport-rated pilot and two passengers were not injured, and the helicopter sank in the Gulf of Mexico, and is presumed to have incurred substantial damage. The flight originated in Belle Chasse, Louisiana, the same day, about 0700.
The Director of Maintenance for Panther Helicopters Inc., stated that the hour-long flight from Belle Chasse, Louisiana to Viosca Knoll, oil platform No. VK817, had initially been uneventful. He further stated, that during the approach to land on the oil platform, while on short final, as the pilot pulled collective to slow the rate of descent there was a power decrease, and the pilot glanced at the gauges and noticed that N2 and Nr had fallen to 90 percent. He said that the helicopter was about 150 feet above the surface of the water, at that time, and was not positioned to land on the platform, so the pilot lowered the collective to maintain rotor rpm, and ditched the helicopter in the Gulf of Mexico. The helicopter was equipped with flotation gear, but it was not deployed. The pilot and passengers exited the helicopter and were rescued by a nearby boat, and the helicopter sank in about 700 feet of water.