N403PH
Bell 407
N5792H
Aerospatiale AS-355-F1
The Bell 407 collided with an Aerospatiale AS-355-F1 while both helicopters were in cruise flight at 1,000 AGL over open ocean in the Gulf of Mexico. Both aircraft were being flown single pilot and were positioning flights between offshore platforms. The pilot of the Bell initiated an autorotation to the water and was rescued. The pilot of the Aerospatiale was fatally injured during the collision/water impact sequence and his helicopter impacted the water and sank into the ocean. Physical evidence on the recovered Bell wreckage indicated that the main rotor blades of the Aerospaciale struck the nose section of the Bell, removing the windshield, chin bubble and anti-torque pedals. The Bell's direct flight course was about 265 degrees. The Aerospatiale's direct course was about 155 degrees. The Bell pilot did not see the Aerospatiale until just before impact. The Helicopter Safety Advisory Conference (HSAC) had published a Recommended Practice (RP) in 1993 for standardized vertical separation of helicopters when flying in the offshore environment. Excerpts are: 'Helicopters operating enroute to and from offshore locations, below 3,000 feet, weather permitting, should use [the following] enroute altitudes; Magnetic Heading of 0 to 179 degrees - 750 feet or 1,750 feet, or 2,750 feet, Magnetic Heading of 180 to 359 degrees - 1,250 feet or 2,250 feet.' These recommended altitudes, if used, provide a minimum of 500 feet vertical clearance. Both operators, who are participating members in HSAC, did not have the HSAC-RP No. 93.1 included in their respective operations manuals. The RP's are recommended and not mandatory.
HISTORY OF FLIGHTS On October 5, 1998, approximately 0906 central daylight time, a Bell 407 helicopter, N403PH, registered to National Leasing Corporation, Louisville, Kentucky, and operated by Petroleum Helicopters Incorporated (PHI), Lafayette, Louisiana, collided in-flight with N5792H, an Aerospatiale AS-355-F1 helicopter, registered to and operated by Tex-Air Helicopters Incorporated, Houston, Texas. Both aircraft were operating over open ocean water in the Gulf of Mexico, approximately 115 miles south of the White Lake VORTAC, and both were destroyed following the collision. The commercial pilot of the Bell executed a forced auto-rotation landing into the water and sustained minor injuries. The Aerospatiale descended into the ocean, and the commercial pilot was fatally injured. There were no passengers onboard either helicopter. Visual meteorological conditions prevailed and respective company flight plans were filed for each of the 14 Code of Federal Regulations (CFR) Part 91 positioning flights. The Bell departed from offshore platform Vermilion 331 at 0857, and was en route westbound to another platform, East Cameron 321A. The Aerospatiale departed a fixed base at Cameron, Louisiana, at 0757, and was en route southeast bound to offshore platform, Vermilion 370. During an interview with the NTSB investigator-in-charge, the pilot of the Bell stated that he was flying at 1,000 feet AGL, on a westerly bearing, when he "heard" the sound of another aircraft. Almost simultaneously after hearing the sound, he saw a helicopter (Aerospatiale) between his "three-thirty and four o'clock" position, seemingly in a hard right turn. Immediately, his reaction was to initiate a "hard" left turn away from the Aerospatiale. After the turn, he noticed that the lower right portion of his helicopter's nose was missing, along with both of the tail rotor anti-torque pedals. Subsequently, the pilot entered an autorotation, transmitted a "MAYDAY" call, and landed the Bell in the water with the skid mounted float system deployed. As the pilot of the Bell recalls, his helicopter remained upright for about "thirty seconds", and as it rolled over, he exited through the pilot side cabin door. Rescuers arrived via helicopter and a boat. The pilot was rescued from the water, and retrieval operations commenced for the Bell helicopter, which inverted in the water, but remained afloat from the deployed floats. A rescue helicopter pilot reported that he "thought" he saw the wreckage of the Aerospatiale in the water before it sank. He also stated that he "thought" he spotted an "empty" life raft in the vicinity, but it was only a "glimpse." During subsequent rescue operations, the Aerospatiale pilot's body was found floating in the water. The only portions of the Aerospatiale recovered were two small sections of the landing gear (skid assembly), both floats (deflated), and three pieces of the under belly fuselage skin. PERSONNEL INFORMATION The pilot of the Aerospatiale held a commercial pilot certificate with rotorcraft-helicopter, and instrument ratings. He successfully completed the competency check required by Title 14 CFR Part 135.293(b) in an Aerospatiale AS-350 helicopter on January 5, 1998. According to FAA records, he held a second-class medical certificate dated March 24, 1998, with no restrictions. He had a total flight time of 3,667 hours (all helicopter time). The pilot of the Bell held a commercial pilot certificate with a rotorcraft-helicopter rating. He successfully completed the competency check required by Title 14 CFR Part 135.293(b) in a Bell BH 206 on November 4, 1997. According to FAA records, he held a first class medical certificate dated June 19, 1998, with no restrictions. He had a total flight time of 2586.3 hours (all helicopter time). AIRCRAFT INFORMATION The Aerospatiale twin-engine helicopter was manufactured in 1983 and had a total airframe time in service of 5,816.1 hours. The aircraft was being maintained in accordance with a manufacturer's inspection program. Maintenance records indicated the last inspection conducted was a 100-hour inspection on September 15, 1998, at 5795.3 hours of total time. Airworthiness Directive compliance records provided by the operator indicated no overdue actions. The latest aircraft status, dated October 6, 1998, indicated three overdue items; altimeter check, pitot static system check, and transponder check, all of which became overdue on September 30, 1998. The aircraft was equipped with two Allison 250-C20F engines with the #1 engine having 4,911.1 hours and 6,971 cycles, and the #2 engine having 4,248.4 hours and 1,078 cycles. An anti-collision warning system was not installed. The Bell 407 single engine helicopter was manufactured in 1997 and had a total airframe time in service of 1,168 hours. The helicopter was being maintained in accordance with an Approved Aircraft Inspection Program (AAIP). Maintenance records indicated that the last inspection conducted was a 50-hour inspection on October 1, 1998 at 1,052 hours total time. Airworthiness Directive compliance records indicated no overdue actions and the aircraft status report indicated no overdue items. The aircraft was equipped with an Allison 250-C47B engine with a total time of 369 hours and 1,552 cycles. An anti-collision warning system was not installed. METEROLOGICAL INFORMATION As reported by the Bell pilot, the wind was from the southeast at 35 knots with gusts to 40 knots, visibility 20 statute miles, scattered clouds at 2,000 feet, and a higher overcast layer above the scattered clouds. There were no reported restrictions to visibility or precipitation. COMMUNICATIONS A review of PHI's flight following logs indicated that the pilot of the Bell filed a flight plan while airborne at 0857. According to taped recordings on the PHI operating frequency, 131.37mhz, a "MAYDAY" call was made at 0906. WRECKAGE AND IMPACT INFORMATION The airframe of the Aerospatiale sank into the ocean and was not recovered. Examination of the pieces found floating on the surface indicated that the skid mounted floats had not been inflated (bottles still charged) and the fuselage skin pieces exhibited hydraulic canning damage. All major components of the Bell were recovered from the water. The main fuselage had moderate to severe damage from the collision and subsequent recovery. The windshield center post was fractured with the upper area of the nose structure adjacent to the right windshield damaged. Damage was noted on both sides of the engine oil tank and the baggage cargo door was missing. The belly section aft of the front right seat was damaged and the chin bubbles were shattered. The pilot's tail rotor pedals were missing due to overload fracture of the mounting plate. The landing gear assembly on the Bell had been removed from the belly attachment fittings to facilitate recovery operations. The left rear float bag had detached from the skid and was missing. The left side of the front crosstube was fractured 6 inches below the step mounting area. A portion of the fracture on the inside of the crosstube bow had a large dent that was oriented 45 degrees to the longitudinal axis of the crosstube. It appeared that the dent and fracture resulted from the crosstube being struck on the right side by a high-energy impact. MEDICAL AND PATHOLOGICAL INFORMATION An autopsy of the pilot of the Aerospatiale was performed at the Calcasieu Parish Coroner's Office in Lake Charles, Louisiana. Toxicological tests were performed by the FAA's Civil Aeromedical Institute (CAMI). According to CAMI, the findings of 63 ug/g acetaminophen, 0.094 ug/g nordiazepam, and 0.383 ug/g oxazepam in the pilot's urine were at low levels. (Nordiazepam and oxazepam are metabolites of diazepam, which is a tranquilizer, commonly known as Valium.) According to the FAA regional flight surgeon, "under normal circumstances, the FAA does not allow the use of tranquilizers or antidepressants while acting as pilot in command." TESTS AND RESEARCH The Helicopter Safety Advisory Conference (HSAC) was formed in 1978 "to promote safe procedures in the operation of rotory-winged aircraft," and its voting membership is comprised of companies that have "direct operating involvement in helicopter operations in the Gulf of Mexico." One of HSAC's Recommended Practices (RP) for offshore helicopter operations is outlined in HSAC-RP No. 93.1. The background of the RP is "to enhance safety through standardized vertical separation of helicopters when flying in the offshore environment." Excerpts are: "Helicopters operating enroute to and from offshore locations, below 3,000 feet, weather permitting, should use enroute altitudes outlined below: Magnetic Heading of 0 to 179 degrees - 750 feet or 1,750 feet, or 2,750 feet Magnetic Heading of 180 to 359 degrees - 1,250 feet or 2,250 feet" These recommended altitudes, if used, provide a minimum of 500 feet vertical clearance. The surviving pilot stated that he was flying at 1,000 feet AGL when the collision occurred. Both operators, who are participating members of HSAC, did not have the HSAC-RP 93.1 in their respective operations manuals. The RP's are "recommended" and not "mandatory." The Bell's direct flight course from Vermilion 331A to East Cameron 321A was about 265 degrees. The Aerospatiale's direct course from Cameron to Vermilion 370 was about 155 degrees. ADDITIONAL INFORMATION The wreckages were released to their respective owners.
the failure of both pilots to see and avoid each other's aircraft during cruise flight. Factors were the failure of both pilots to use a known safety advisory recommendation and the failure of both operators to implement the recommendation as a company operating procedure.
Source: NTSB Aviation Accident Database
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