NTSB Identification: DFW08FA053
Nonscheduled 14 CFR Part 135: Air Taxi & Commuter
Accident occurred Saturday, December 29, 2007 in Venice, LA
Probable Cause Approval Date: 07/15/2009
Aircraft: Bell 206L1, registration: N211EL
Injuries: 1 Fatal,1 Serious,2 Minor.
NTSB investigators either traveled in support of this investigation or conducted a significant amount of investigative work without any travel, and used data obtained from various sources to prepare this aircraft accident report.
According to an interview with the pilot, while en route to an unmanned offshore platform South Pass 38 in the Gulf of Mexico, the cloud ceilings were about 500 feet and the visibility was about 5 miles. However, as the helicopter neared the destination platform, the flight entered deteriorating weather. The pilot estimated that the cloud ceiling was about 300 feet and that the visibility was about 1 mile when he began circling to land on the platform. Although the weather conditions did not meet Air Logistics’ operating minimums, which required a 500 foot cloud ceiling and 3 miles of visibility, the pilot decided to continue to the destination platform, despite having the option to divert to another station.
About 1 mile from the platform, as the pilot was maneuvering in an attempt to reduce the airspeed, the helicopter began an inadvertent descent and then entered an aerodynamic buffet that hindered the pilot’s ability to maintain straight and level flight. The buffet was most likely caused by the helicopter entering transverse flow effect (unequal lift vectors between the front and rear portions of the rotor disc) and by a reduction in lift vectors, which resulted from the tailwind that was present. After encountering the buffet, the pilot was unable to maintain control of the helicopter or to stop the helicopter’s descent before it impacted the water.
The accident helicopter was equipped with externally mounted floats, which could have been deployed by actuating a trigger mounted on the cyclic. The helicopter was also equipped with two externally mounted liferafts that could have been deployed either by pulling an interior T-handle near the pilot’s left leg or by pulling one of the two externally mounted T-handles on the helicopter’s skid cross bar. According to a supplemental type certificate for the helicopter, a placard was only mounted near the interior T-handle.
According to a pilot interview and a written statement obtained by Air Logistics, the pilot did not attempt to activate the helicopter’s flotation system or liferafts before water impact because he was preoccupied with recovering from the buffet. The accident pilot provided no indication why he did not deploy the external liferafts using the internal T-handle when the helicopter entered the water, even though he had received training on external liferaft deployments. Air Logistics’ training program and operating manual expected company pilots to deploy the floats before water impact but did not address pilot expectations in the event of water impact without floats deployed. Lacking additional guidance, the pilot reverted to his water survival training and immediately exited the helicopter.
All of the occupants survived the impact, exited the helicopter, and inflated their lifejackets. The pilot was unable to reach the external liferaft T-handles on the skids and attempted to direct the passengers to deploy the liferafts. However, because the pilot had not conducted a passenger briefing (including instructions on how to deploy the liferaft system), the passengers did not know that liferafts were available externally and did not understand how to deploy the liferafts using the external T-handles before the helicopter sank. Under 14 CFR 135.117, the Federal Aviation Administration (FAA) requires pilots to ensure that, before flight, all passengers on flights involving extended overwater operations are orally briefed on ditching procedures and the use of required flotation equipment; however, the accident flight did not meet the 14 CFR 1.1 definition of an extended overwater operation because it was operating within 50 nautical miles of the shoreline.
Per the Air Logistics flight operations manual (FOM), a passenger briefing was required that would have included the location of emergency equipment, such as seat belts, exits, lifejackets, and fire extinguishers. The FOM did not specify that liferaft locations were to be part of the briefing. Regardless, no passenger safety briefing was provided before departure. Air Logistics passenger briefing cards, which were stowed in a pouch on the cabin sidewall for each passenger seat, provided directions on how to operate different emergency equipment; however, the briefing cards did not provide guidance on which equipment was installed on the helicopter. In addition, at the time of the accident, there were no placards to aid in recognition of the external liferaft activation handles.
The passengers and the pilot attempted to swim to the platform, which was about 100 yards from the impact location, but were separated by high waves and were moved away from the platform by the current. About 1551, an Air Logistics radio operator mistakenly recorded the helicopter as “landed” in the company’s flight-following database. Because the helicopter was placed in the “landed” status, the flight-tracking program did not trigger any overdue notifications. About 34 minutes later (1 hour after the crash), the error was discovered by the Air Logistics base manager in Venice, Louisiana, because the pilot had not reported his status before sunset. As a result, the company diverted a field boat toward the offshore platform to search for the helicopter; however, the field boat was too far away to aid the survivors. The weather conditions precluded the launch of another helicopter to assist in the search. About 1 hour 15 minutes after the crash, the crewmembers of a shrimp trawler contacted the U.S. Coast Guard to report that they had retrieved two survivors and a deceased passenger from the water. The water temperature near the accident location was about 49 degrees Fahrenheit, and the passenger died of hypothermia secondary to asphyxia from drowning. A Coast Guard ship rescued the severely hypothermic pilot more than 4 hours after the estimated time of the crash.
The pilot did not report engine power loss or control malfunction. The passengers did not report seeing any warning lights or hearing any aural warnings before the accident. An examination of the airframe and engine did not reveal any anomalies that would have precluded safe flight or the production of engine power.
On October 20, 2008, the NTSB issued two recommendations pertaining to this accident. Safety Recommendation A-08-83 asked for the installation of a placard for each external T handle on turbine-powered helicopters with externally mounted liferafts that clearly identifies the location of and provides activation instructions for the handle. Safety Recommendation A 08-84 recommended that all operators of turbine-powered helicopters be required to include information about the location and activation of internal or external liferafts in pilot preflight safety briefings to passengers before each takeoff. Both recommendations are classified “Open—Response Received.”
Safety Recommendation A-07-88, which the NTSB issued on October 19, 2007, also applies to this accident. In the recommendation, the NTSB asked the FAA to require that all offshore helicopter operators in the Gulf of Mexico provide their flight crews with beacon-equipped personal flotation devices; Safety Recommendation A-07-88 is currently classified “Open—Acceptable Response,” based on the FAA’s plan to consult with operators on the best ways to increase the chance of survival in a ditching and the issuance of an information for operators that describes recommendations to mitigate the risks and hazards for helicopters that may have to ditch in the Gulf. As a result of the accident, Air Logistics has initiated a program requiring that each pilot be provided a lifejacket equipped with a 406-megahertz emergency position indicating radio beacon that has full two-way voice capability and that is waterproof to 10 meters. This program requirement is consistent with the intent of the recommendation even without the FAA requiring it.
Additionally, personal locator beacons (without two-way voice capability) have been installed in Air Logistics liferafts. Air Logistics also has started installing water-activated switches on the flotation system and liferafts for its Bell 407 helicopters; the switches are being installed during each helicopter’s next maintenance or inspection visit. Placards have also been placed on the underside of aircraft showing the mechanism for manual deployment of liferafts when the aircraft is upside down in the water. To standardize the briefing information given to passengers, the preflight briefing checklist, passenger briefing cards, and passenger briefing tapes have been revised to include information on the location and operation of liferafts.
In addition, the company produced an initial and recurrent training video to include more detailed information on how to deploy the flotation system and liferafts installed on its helicopters, including footage of an actual deployment, and has revamped its aircraft type-specific briefing videos for passengers. The training and briefing videos are shown to all first-time passengers before they depart their shore base. Air Logistics also has a separate video specifically on raft and float deployment, which includes manual deployment from outside the aircraft; according to the company, this video usually runs continually in the waiting rooms at the shore base. Thus far, Air Logistics pilots and passengers have given positive feedback on the training and briefing videos.
To address the problem of misreporting helicopter status, a senior company pilot now assists the radio operator with oversight of helicopters, and helicopter pilots are required to provide position reports every 30 minutes, regardless of whether their helicopter is airborne or has landed. The radio operator and the senior pilot monitor any pilot who requests a longer delay to eat lunch or take a restroom break, for example. Also, to eliminate inadvertent changes in helicopter status, an additional keystroke has been added to confirm that a helicopter has landed.
The National Transportation Safety Board determines the probable cause(s) of this accident to be: The pilot’s decision to continue to the destination landing platform in weather conditions below the company’s weather minimums and his failure to maintain aircraft control during the approach. Contributing to the passenger fatality and the severity of the occupant injuries were the lack of a passenger briefing on how to deploy the liferaft, which was required by the company but not by the Federal Aviation Administration because this flight was not an extended overwater operation; the pilot’s failure to deploy the liferafts; and the company radio operator’s misreporting of the helicopter’s “landed” status, which delayed the rescue response. Full narrative available
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