"The employee said the pilot then simultaneously brought the helicopter up off the pad and forward. He described the takeoff as "kind of shaky." He said that on other flights, pilots will normally bring the helicopter into a hover, do an instrument check, and then start forward flight. However, in the three times he had flown with the accident pilot, he always took off without hovering."
"The following is an INTERIM FACTUAL SUMMARY of this accident investigation. A final report that includes all pertinent facts, conditions, and circumstances of the accident will be issued upon completion, along with the Safety Board's analysis and probable cause of the accident:"
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HISTORY OF FLIGHT
On October 9, 2013, about 0720 central daylight time, a Bell 206L-3, N54LP, was substantially damaged when it impacted water shortly after takeoff from the Main Pass 107D oil platform in the Gulf of Mexico. The commercial pilot was fatally injured and the three passengers were seriously injured. The helicopter was registered to and operated by Panther Helicopters, Inc., Belle Chasse, Louisiana. A company visual flight rules flight plan was filed for the flight that was destined for the Belle Chasse Heliport (06LA), Belle Chasse, Louisiana. Visual meteorological conditions prevailed for the business flight that was conducted under the provisions of 14 Code of Federal Regulations Part 135.
The purpose of the flight was a routine crew change at the MP107D oil platform. The pilot and three oil platform employees departed 06LA about 0633 and flew direct to the platform. The crew change consisted of dropping the three platform employees off, picking up three other employees, then returning to 06LA. After landing on the platform, the pilot did not shut down the helicopter down and stayed at the controls with the main rotor turning until the crew change was complete.
A witness was standing on the MP108E oil platform, which was about 300-400 yards from MP107D. He had a clear and unobstructed view of the MP107D platform and saw the helicopter sitting on the helipad with its main rotor blades turning. The helicopter was facing east-northeast. The witness said that he saw three people get off the helicopter and then three other people get on the helicopter. He described the weather as "stale" and the wind sock was "limp."
About 1 to 2 minutes later, the witness observed the helicopter pull up into a 3 to 4-foot-high hover over the helipad and make a slight bearing change toward the east. He said at that point, everything was completely normal with the helicopter. The helicopter then moved forward and started to take off toward the east. The witness said as soon as the helicopter cleared the helipad's skirting, he saw a flash and a large (10-foot-high x 10-foot-wide) "poof" or "cloud" of white smoke come from directly under the main rotor blades near the exhaust section of the helicopter. This was followed by a loud, high-pitched, screeching noise, as if the engine were being revved up. The witness said this "poof" of smoke occurred when the helicopter was parallel to a flare boom that extended directly out from the platform and was positioned on the north side of the helipad. The witness said that after he saw the "poof" of smoke, the helicopter nosed over toward the water. The helicopter cleared the helipad's skirting and did not strike the flare boom as it descended.
The witness said he saw the helicopter's emergency floats fully expand before it impacted the water. The helicopter hit the water hard with the main rotors still turning; became completely submerged and rolled inverted. The wintess could see the helicopter's skids near the surface of the water and noted that one emergency float (he could not recall which one) had completely separated from the helicopter.
The witness did not see anyone coming to the surface and used his VHF handheld radio to issue a "may-day-call." He also directed a field boat, which was at the base of the MP108E platform, to the helicopter. He said that by the time the boat arrived, two deck hands were already stripped down and jumped into the jellyfish infested water to help the occupants of the helicopter. Although one of the deckhands had an allergic reaction to the jellyfish stings, they were able to get three of the four occupants out of the helicopter and onto the field boat. The pilot's feet were "caught up in the controls" and it took about 15 minutes for them to get him freed.
The witness said he did not see any methane gas being vented from the flare boom on the morning of the accident; however, he did see a large (size of an automobile) "methane cloud" coming from the flare boom the day before the accident between 12 and 5 pm. The methane cloud was located right where he saw the poof of white smoke on the day of the accident. The witness said he has seen methane being vented from the MP107D flare boom on several occasions. He said they vent "a lot of gas" several times a week.
In a telephone conversation, a platform employee, who was a passenger on the helicopter, stated that he had just completed a 14-day "hitch" on the MP107D oil platform and was headed back to Louisiana. On the morning of the accident, he and the two other platform employees prepared the platform for a crew change and waited for the helicopter to arrive. The employee said that after the pilot landed, he briefly talked to one of the on coming employees about a hunting trip. He then loaded his bags and was the last one to board the helicopter. The employee said he got in the helicopter via the left rear door and sat in the left seat, facing forward. The passenger then donned an inflatable life vest, put on a headset, and fastened his seatbelt. He tugged on the seatbelt to make sure it was secure and snug.
The employee said that once everyone was fastened in, they gave the pilot a "thumbs-up" and the pilot prepared to depart. At this point, everything regarding the flight was "normal."
The employee said the pilot lifted the helicopter up off the platform and began forward flight. When the helicopter was over the water, he heard a loud noise overhead as if the transmission was coming a part. The other passenger that was seated next to him asked, "What's that?" The employee told him to "hold on," and the next thing he knew they hit the water with a "big splash." Prior to impact, he did not hear any alarms going off in the cockpit and did not remember the emergency floats expanding. The pilot did not say anything during the accident sequence.
The employee stated that he may have passed out for a few minutes. When he regained consciousness, he realized he was out of his seatbelt (he did not recall unfastening the buckle). The helicopter had rolled on-to its left side, and he was trying to find the door. When he tried to stand up, he realized he couldn't feel his legs. At this point, the passenger, who had been seated next to him had opened the right door and was climbing out. Although water was entering the cabin, he and the passenger in the front left seat were able to keep their heads above water. There was no movement or response from the pilot.
The passenger said that he sat there for a few minutes, and when the helicopter began to roll inverted, he was able to push himself out of the right rear door where the other rear seat passenger had been sitting. He then tried to inflate his life vest, but when he pulled on the inflation-lanyard it would not inflate. He said that he was not familiar with this particular model vest and he did not try to self-inflate the vest. Shortly after, the front seat passenger was able to get out of the helicopter. The two rescuers who dove in the water from the life boat were trying to get the pilot out, but his seatbelt was "too tight," and his foot was stuck in the windshield.
The employee said that while the pilot was being extracted, the other rear seat passenger was dragged to the life boat via a life ring. At this time, the employee saw a life vest floating in the water. He was able to inflate it and used it to support himself until he was rescued. The employee said he was in a "panic state of mind" and didn't recall getting onto the boat.
In a telephone conversation, another platform employee, who was also a passenger on the accident flight, stated that he had just completed a 14-day "hitch" on the MP107D oil platform. He said that on the morning of the accident, he and the two other employees prepared the platform to be turned over to the on-coming crew. While eating breakfast, he heard the pilot make a radio call that he was 10 minutes out with three onboard. The employee said the platform's lead operator responded to the pilot, and told him he had a "green deck" to land. The employee then grabbed his bags and headed up to the helipad. After the helicopter landed, the three on-coming crew members got off the helicopter and retrieved their bags from the cargo bay. The employee said he placed his bags in the cargo bay and walked around the front of the helicopter. The pilot gave him a "thumbs-up" and a smile, and then the employee got in the helicopter. He sat in the rear of the helicopter on the right side, facing forward. He donned the provided inflatable life vest, a headset, and fastened his seatbelt assembly. The employee said another employee sat next to him on the left side, forward facing seat and the other sat in the front left seat.
The employee said he did not talk to the pilot or notice anything unusual about his behavior. After the crew was onboard, the pilot asked if they were ready to go and they responded they were ready. The employee said the pilot then simultaneously brought the helicopter up off the pad and forward. He described the takeoff as "kind of shaky." He said that on other flights, pilots will normally bring the helicopter into a hover, do an instrument check, and then start forward flight. However, in the three times he had flown with the accident pilot, he always took off without hovering.
The employee said that once the helicopter moved off the helipad and over the water, there was a "winding noise" then a "pop" sound. His first instinct was that there was a problem with the transmission. He did not hear alarms going off in the cockpit or see any annunciator lights. The helicopter then nosed over at an angle toward the water. The employee said that as the helicopter descended, the emergency floats expanded just before they hit the water. He described the impact as a "big ole crash like landing on concrete." The employee said that he then heard moans of pain coming from the other men onboard and that water started to enter the cabin. The helicopter had rolled on to its left side. He then undid his seatbelt and opened the right cabin door. The employee said he turned left and asked the passenger next to him if he was okay, and he responded that he could not feel his legs. The employee said the passenger had come completely out of his seatbelt during the impact.
The employee exited the helicopter and held onto the skid of the helicopter because when he pulled on his life vest inflation-lanyard, it did not expand. He said the rear seat passenger's life vest also wouldn't inflate but the passenger's vest on the front seat did inflate. He was not sure about the pilot's life vest.
The employee said he saw the lift boat and told the rescuers there were three more people on board. He was able to get onto the life boat, where he laid down until help arrived.
The employee reiterated several times there was nothing mechanically wrong with the helicopter until they started to takeoff. He said the platform was not venting methane that morning and the wind was calm.
In a telephone conversation, one of the platform employees, who had just been dropped off at the platform, stated that he and the two other platform employees arrived at Panther Helicopter's facility in Belle Chasse, Louisiana, on the morning of the accident around 0600. He said all three of them signed in and waited for the helicopter to be ready. When they were ready to board, he got in the front left seat, put on his life vest and fastened his seatbelt. The pilot made sure everyone was wearing their life vests and seatbelts before they departed. While en route, the employee said he briefly spoke to the pilot and he did not notice anything unusual with his demeanor. He said the helicopter was operating fine and there were no indications of any problems.
The employee said that after a normal landing, he exited the helicopter, retrieved his bags from the cargo bay, and went downstairs into the platform housing. There he had a quick changeover briefing with the departing-lead. Several minutes later, he heard the helicopter's engine spool up as it prepared to takeoff. Everything sounded normal until he heard a "pop" and a high-pitched whine followed by a low pitch whine as if the engine were spooling down. He described the noise as a turbine or compressor winding down. At that point, the employee knew something was wrong and ran outside. Once outside, he saw the helicopter in the water on its right side and one passenger was exiting the helicopter. The employee said he went back inside and called the Coast Guard, Panther Helicopters, and his senior management.
According to the operator, the helicopter was equipped with a SkyConnect tracking system. The last registered altitude of the helicopter was about 141 feet.
PILOT INFORMATION
The pilot held a private pilot certificate for airplane single-engine land and a commercial pilot certificate for rotorcraft-helicopter. His last Federal Aviation Administration (FAA) second class medical was issued on January 10, 2013. According to the operator, the pilot had accrued a total of 3,450 total hours; of which 3,423 hours were in helicopters, and 177 hours were in the same make/model as the accident helicopter.
The pilot was hired by Panther on June 17, 2013. His training was conducted by Panther in the Bell 206 helicopter. The pilot successfully completed his CFR Part 135.293 and 135.299 FAA check ride on July 25, 2013.
AIRCRAFT INFORMATION
N54LP was a 1991 Bell 206L-3 helicopter with serial number 51466. The single-engine helicopter was powered by an Allison M250-C30P turbo-shaft engine with serial number CAE 895524, which drove a two-bladed main rotor system and a two-bladed tail rotor. The helicopter was configured to carry one pilot and six passengers.
According to the operator, the helicopter was maintained in accordance with the manufacturer's continuous inspection program. The helicopter's last inspection (event 2) was completed on October 3, 2013. The helicopter's total time at the time of the accident was 11,238 hours.
METEOROLOGICAL INFORMATION
At 0600, weather conditions at the Belle Chasse heliport, Belle Chasse, Louisiana, about 72 nautical miles northwest of the accident site were calm wind, visibility 10 miles and clear skies, with a temperature of 65 degrees Fahrenheit.
At 0655, weather conditions at the New Orleans Naval Air Station (NBG), Louisiana, about 72 miles northwest of the accident site were calm winds, visibility 10 statute miles with shallow fog, few clouds at 5,000 feet, temperature 57 degrees F, dew point 60 degrees F, and altimeter 30.06 inches of Mercury.
AIRPORT INFORMATION
According to the Bureau of Safety and Environmental Enforcement, the Gulf of Mexico is divided into three primary subdivisions: Western Gulf of Mexico, Central Gulf of Mexico, and Eastern Gulf of Mexico. The three subdivisions are further divided into areas and blocks. The blocks are about 3 miles long and 3 miles wide and are used for oil/gas lease identification. There are over 2,600 offshore production platforms in the Gulf of Mexico region.
MP107D is an offshore oil production platform, (29 degrees 30 minutes north latitude and 88 degrees 42 minutes west longitude). MP107D is about 37 nautical miles northeast of Venice, Louisiana. MP107D features a single helideck (about 35-feet-long and 35-feet-wide).
WRECKAGE INFORMATION
The wreckage was recovered and moved to Panther's maintenance facility in Belle Chasse, Louisiana. The National Transportation Safety Board (NTSB) Investigator-in-Charge conducted an examination of the airframe and a visual examination of the engine on October 14, 2013. Also present for the examination were representatives of Panther, Rolls Royce, and Bell Helicopter.
The helicopter was secured and upright on a flatbed trailer. The engine, transmission, and main rotor system remained attached to the airframe. One of the main rotor blades had been cut off for transport and the other blade was fractured during the impact with the water. The section of fractured blade was never located. The tail boom had separated from the fuselage about 12-inches aft of the tail boom attachment point. The tail rotor assembly had separated aft of the elevator and was never recovered.
The entire windshield on the right side of the helicopter was missing, and a large section of windshield was missing on the left side. The forward and aft passenger doors were removed. The aft cargo bay was crushed upward from the bottom of the fuselage. Salt water corrosion was noted throughout the fuselage and engine.
Flight control continuity was confirmed for the cyclic and the collective to the main rotor system. Partial flight control continuity was established for the anti-torque pedals from the cockpit to the point where the tail boom had separated from the fuselage.
The throttle was locked in the fuel-cutoff position, which was consistent with the setting on the fuel control unit.
Examination of the pilot's 4-point shoulder harness/seatbelt assembly revealed that it was secure at all fuselage attach points. The inertial reel was locked, and stretch marks on the belt material were observed in several locations. The latching mechanism functioned normally when manually tested.
The front seat passenger's 4-point shoulder harness/seatbelt assembly was also secure at all fuselage attach points and functioned normally when manually tested. The inertial reel was not locked.
The metal seatbox for the front passenger's seats was crushed downward.
All of the rear seat shoulder harness/seatbelt assemblies were secured at their respective fuselage attachment points and the latching mechanisms functioned normally when manually tested.
A visual examination of the engine revealed that it did not sustain much impact damage; however, several large holes were observed in the exhaust collector support stack. A hole was also observed in the cowling on the right side near the area of the support stack. Oil was in the bottom of the engine pan and the forward engine mounts were slightly bent. All engine fuel, oil and pneumatic lines, and b-nut fittings were tight and no leaks were observed.
The engine was removed and shipped to Rolls Royce, where a tear down examination was conducted on November 6-7, 2013, under the supervision of an NTSB investigator. Representatives of the FAA, Rolls Royce, Panther and Bell Helicopter were also present for the exam.
The centrifugal compressor section was disassembled. The #1 and #2 bearings were examined and found to be free of any indications of distress. The compressor impellor vanes exhibited slight indications of rotational rubbing; however, no other indications of ingestion or other damage were noted.
The gearbox was disassembled. Examination of internal components did not reveal any obvious defects to gearing. The gearbox interior contained a large quantity of the magnesium gearbox case, corrosion deposits and material from the effects of sea water immersion and recovery operations.
The gas generator turbine and power turbine sections were disassembled. The Stage 1 turbine section was undamaged. The Stage 2 section revealed damage to the turbine disk blades, with one blade liberated from the blade root. All of the Stage 3 turbine disk blades were liberated at the blade roots. All of the Stage 4 turbine disk blades were damaged, with about 320 degrees of the blade shrouds detached. The blades did not breach the turbine cases.
The turbine section stages were retained and are currently undergoing metallurgical examination.
MEDICAL AND PATHOLOGICAL INFORMATION
Toxicological testing was conducted by the FAA Toxicology and Accident Research Laboratory, Oklahoma City, Oklahoma. The pilot tested positive for Cetirizine in his blood and urine. Diphenhydramine was detected in his urine and blood (.024ug/ml, ug/g). In addition, Ibuprofen was detected in the pilot's urine.
Editor's note: During annual recurrent ground school recently, the instructor mentioned that pushing forward on the cyclic immediately following an engine failure out-of-ground-effect will result in loss of rotor rpm. The urge to push forward must be resisted until the rotor system completes it's transition from normal thrusting state (air being driven down through the rotor system) to autorotational state, (air passing up through the rotor system and driving the rotor). The indication that this transition is complete is an increase in rotor rpm...
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