NTSB Identification: CEN12FA321
Nonscheduled 14 CFR Part 135: Air Taxi & Commuter
Accident occurred Monday, May 28, 2012 in
Aircraft: BELL 206-L4, registration: N7077F
Injuries: 1 Fatal.
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 May 28, 2012, approximately 1610 central daylight time, N7077F, a Bell 206-L4 helicopter, was substantially damaged when it collided with the Ensco 99 oil rig derrick while on approach to the South Timbalier (ST67B) production platform in the Gulf of Mexico. The commercial pilot, only occupant, was fatally injured. The helicopter was registered to and operated by PHI INC, Lafayette, Louisiana. A company visual flight rules flight plan was filed for the flight that originated from its base in Grand Isle, Louisiana, at 1514, and destined for the Mississippi Canyon (MC397) and ST67B oil platforms. The pilot landed at MC397 at 1541, dropped off a box, and then departed for ST67B at 1543 to pick up a passenger. Visual meteorological conditions prevailed for the on-demand offshore flight conducted under 14 Code of Federal Regulations Part 135.
The ST67B production platform is a permanent structure equipped with a 24-foot-long by 24-foot-wide helipad with a 3-foot-wide solid safety fence. The Ensco 99 oil rig, which is a mobile jack-up rig, was connected on the northside of the ST67B platform and had been in place for approximately four months. The Ensco 99 rig, which was being operated by Ensco for Energy XXI, was also equipped with a helipad that was 65 feet in diameter. At the time of the accident, the Ensco 99 oil derrick was positioned over the ST67B helipad by approximately seven feet. The height above the helipad to the bottom of the derrick floor was approximately 30-35 feet. There was also a lift boat, the Alliance I, stationed at the southeast corner of the two rigs. The boat was staffed with a captain, first mate, and crew.
The captain and first mate of the Alliance I witnessed the accident. According to the captain, he was sitting in his office on the boat when he heard the helicopter approaching. It alarmed him because the noise of the helicopter was so loud and he thought the ST67B helipad was closed because of the oil derrick's position over the pad. He watched as the helicopter approached the pad and he could see a worker on the Ensco 99 rig trying to wave the pilot off from landing. Due to the relatively close proximity of the helicopter to the boat, the captain thought he saw the pilot trying to "pull back" but "it was too late" and the main rotor blades struck the southeast corner of the oil derrick. The helicopter then spun rapidly and the tail boom separated from the fuselage. The helicopter flipped and descended into the water inverted. The Captain immediately sounded the general alarm. The emergency floats on the helicopter were not deployed and the helicopter began to sink. In less than a minute, rescue boats were in the water but the helicopter had already sunk from view below the surface. The captain said he had never seen a pilot make an attempt to land on the ST67B helipad before.
The first mate said he was in the boat’s wheelhouse when he heard the helicopter approaching. He looked outside the window and saw the skids of the helicopter going by. He said was concerned because he thought the ST67B helipad was out of service due to the close proximity of the oil derrick over the helipad. The first mate was watching a person on the Ensco 99 rig trying to wave the pilot off from continuing the approach when he heard a “pop, pop, pop” noise. At that moment, he knew immediately that the main rotor blades struck the base of the oil derrick. When he looked back at the helicopter it had spun around suddenly and he thought the tail rotor struck the helipad. He said, “The helicopter jumped violently and the tail seemed to fold and the chopper fell along the northeast side of the platform…” The first mate then assisted the captain and other parties in an attempt to rescue any survivors. The first mate said that he has never seen a pilot attempt to land on the ST67B pad before.
Another witness was working on the north side of the oil derrick when he heard the helicopter make two passes around the oil rig. He then heard the helicopter approaching the ST67B helipad and it sounded "normal." Shortly after, the witness heard the main rotor blades impact the base of the oil derrick (rig floor). The witness then rushed down a set of stairs on the east side of the rig floor and looked over the railing. At that point, he saw that the tailboom had separated from the fuselage, and both sections were descending into the water. The witness stated that he had been stationed on the Ensco 99 rig for approximately four months and he had never seen a helicopter land on the ST67B helipad.
According to the Ensco 99 Offshore Installation Manager (OIM), the passenger that the pilot was to pick up was waiting in the Ensco 99 waiting area, which was just south of the Ensco 99 helipad. He also said that the oil derrick had been positioned over the ST67B helipad for approximately 3 months since they were drilling on a specific well. The OIM had been stationed on the Ensco 99 for approximately 4 months and had never seen a helicopter land on the ST67B helipad. He said that the pilots always used the Ensco 99 helipad.
According to PHI, a Notice to Airmen (NOTAMs) declaring the ST67B helipad "closed" due to encroachment of the oil derrick had not been issued prior to the accident. After the accident, PHI issued a NOTAM that stated the helipad was closed. In addition, Energy XXI had a red "X" painted on the helipad.
The helicopter wreckage was recovered several hours after the accident and transported to PHI’s facility in Lafayette. The wreckage was examined on May 30, 2012, under the supervision of the NTSB investigator-in-Charge. The helicopter sustained impact damage on the left side of the nose and along the left side of the fuselage. The roof of the fuselage was partially crushed into the cabin and the skids were spread.
The tail boom had separated from the fuselage at the point where the tail boom attached to the fuselage. The tail boom exhibited minor damage. The tail rotor assembly and both blades were not damaged; however, the main rotor blades exhibited impact damage and were fragmented. Both main rotor blades remained attached to the mast, but only about four feet of each blade remained. The missing pieces of the main rotor blades were not recovered. Flight control continuity was established for all flight controls to the cockpit.
The helicopter was equipped with an Intellistar engine monitor, which was removed for further examination and download.
The emergency external float system was intact, so it was manually activated from the cockpit during the wreckage examination. All but the middle float on the right rear expanded fully.
The pilot’s seat (front right) was intact and no visible damage was noted to the seat frame or box. The front right door was not damaged and functioned normally when tested. The pilot's 4-point seatbelt/shoulder harness assembly was intact and both the lap belt buckle and inertial reel system worked when manually tested. According to information provided by the company that recovered the helicopter, the pilot was found upright inside the cockpit of the helicopter and his seatbelt/shoulder harness assembly was not fastened.
The pilot was wearing his company issued life vest at the time of the accident and the two bladders were found outside of their vest pockets. The life vest was retained and examined. The vest had two bladders that could be inflated manually by pulling down on two pull-tabs on the front of the vest (one for each bladder). When the tab is pulled it activates an 02 cartridge. Once the cartridge is activated, a red locking pin built into the system is sheared. Examination of the O2 cartridge on the left side of the pilot's vest (which feeds the front bladder) revealed that the red locking pin was sheared and the O2 cartridge had been activated. Examination of the front bladder revealed a 3-inch-long diagonal tear on the front left side of the bladder. The tear appeared to have been made with a sharp object. The seams of the bladder were inspected and no other tears/leaks were noted. Examination of the red locking pin on the right O2 cartridge assembly (which feeds the rear bladder) revealed it was intact and the cartridge had not been activated. No tears or leaks were observed in the rear bladder. The O2 cartridge was then activated and the bladder filled immediately with air.
The pilot held a commercial pilot certificate for rotorcraft-helicopter, and instrument helicopter. His last Federal Aviation Administration (FAA) First Class medical was issued July 18, 2011. A review of company records and also one of the pilot’s logbooks found in the helicopter, revealed he had accrued approximately 1,645.1 hours; of which 363 hours were in Bell 206-L3/4 model helicopters.
Weather at Fourchon, Louisiana (K9F2), approximately 15 miles north of ST67B, at 1700, was reported as wind from 240 degrees at 12 knots, visibility 7 miles, few clouds 3,000 feet, temperature 32 degrees Celsius, dewpoint 25 degrees Celsius, and an altimeter setting of 29.87 inches of Hg.