Aviation Accident Summaries

Aviation Accident Summary DFW05MA230

Gulf of Mexico, TX, USA

Aircraft #1

N90421

SIKORSKY S76

Analysis

About 18 minutes into the flight, the No. 1 (left) engine fire warning light illuminated in the cockpit, followed by several additional engine warnings and visible smoke in the cockpit and passenger compartment, according to crew and passenger interviews. After the fire and smoke indications, the helicopter lost power to both engines, and the flight crew executed a forced landing into the open waters of the Gulf of Mexico. The helicopter wreckage was located, and the cockpit voice recorder (CVR) was recovered shortly after the accident; however, efforts to recover the remainder of the wreckage were suspended due to an approaching hurricane. The wreckage could not be located following the hurricane; therefore, the cause of the in-flight fire warnings and the loss of power to both engines could not be determined. After the first engine fire warning, CVR evidence revealed that, contrary to their training and the helicopter manufacturer's guidance, neither pilot acknowledged the fire warning, called for a checklist, or verbalized a plan of action. According to the Sikorsky S-76A Flight Manual, the emergency procedures for responding to an engine fire warning include pressing the fire warning light, establishing safe single-engine flight airspeed (76 knots), fully retarding the affected engine's illuminated T-handle (a handle located on the engine throttle quadrant above and in front of the pilots, which, when pulled, stops the flow of fuel to that engine and releases a fire suppressant), and, if necessary, selecting and activating the fire extinguishing system. The pilots, who had been on duty for more than 10 hours and had completed 13 landings that day, only completed the first step during the 2 minutes before impact with water; therefore, the pilots failed to follow emergency procedures in response to the engine fire warning. National Transportation Safety Board performance calculations indicated that, if the pilots had immediately completed the first three steps in responding to the No. 1 engine fire warning, as required, they may have been able to maintain single-engine flight to a suitable landing location on an off-shore platform before the No. 2 engine failed. The investigation revealed additional flight crew performance deficiencies. For example, although the first officer transmitted a "mayday" call before the second engine failure and about 1.5 minutes after the first warning indication, he did not provide essential information needed to obtain emergency assistance. He also did not inform the passengers that they were executing a forced landing into the water. Before flight, the flight crew did not provide the required preflight passenger safety briefing, which would have included instructions on how to retrieve and inflate a liferaft; the passengers did not retrieve either of the two liferafts. All of these performance deficiencies are consistent with the known effects of situational stress (in this case associated with the emergency) and fatigue (associated with a long, demanding day of flying), both of which likely degraded the pilots' performance. The flight crew did not file a flight plan with either the Federal Aviation Administration (FAA) or HHI, contrary to company procedures. Although Houston area air traffic control (ATC) facilities were monitoring emergency frequencies, controllers did not hear the distress call because the helicopter was well outside and below ATC radio coverage when the transmission was made. Commercial and military pilots in the area reported hearing the distress call to various ATC facilities; however, none of the reporting pilots could provide any additional information about the distressed aircraft because the first officer had only stated, "mayday ... Houston 421... going in" and did not provide a location or type of emergency. At the time of the accident, neither HHI's communication network nor Gulf of Mexico offshore cellular towers were functioning as a result of Hurricane Katrina, and the company did not provide an alternate means for its pilots to communicate with base operations. Instead, HHI suggested that pilots use their personal satellite cell phones or request assistance from oil platform personnel to relay information to base operations. The accident pilot reported that he was reluctant to use his personal satellite cell phone because HHI would not reimburse him for the calls. Regardless, flight crews were expected to contact an FAA automated flight service station if they could not contact base operations, and the accident flight crew did neither. If the accident flight crew had been reporting in every 15 minutes, as required by the company's OpsSpec, the HHI radio operator would have been alerted when the accident pilots missed a reporting time and HHI would have had more information about the accident location. HHI did not report the overdue helicopter to the FAA until almost 2 hours after the flight was expected back at homebase. As evidenced by this accident, HHI did not ensure that its pilots were adhering to flight-following procedures and did not have adequate procedures for reporting overdue flights; both of these deficiencies also delayed the initiation of the search and rescue efforts. As a result of this accident and others, the Safety Board recommended to the FAA that "all offshore helicopter operators in the Gulf of Mexico provide their flight crews with personal flotation devices equipped with a waterproof, 406 megahertz personal locator beacon equipped with an enabled global positioning-system, as well as one other signaling device, such as a signaling mirror or a strobe light." (A-07-88) The 7.5 hours that the passengers spent in the water exposed them to hypothermia-inducing conditions, and the lack of a 406 megahertz personal locator beacon and another signaling device delayed their rescue. The recommendation was classified "Open-Acceptable Response," on July 25, 2008, pending the results of FAA meetings with industry and possible issuance of rulemaking. As early as 2003, the FAA was aware of safety deficiencies at HHI, including lack of passenger safety briefings and inadequate flight-locating procedure training for dispatchers. In February 2005, the newly assigned principal operations inspector recorded HHI's lack of adherence to flight-locating procedures. Despite his efforts in August 2005 to suspend operations at HHI until the deficiencies were addressed, the Houston flight service district office manager gave HHI an extension on the morning of the accident because of the urgent need for helicopter services following Hurricane Katrina. After the loss of communications following Hurricane Katrina, the FAA improperly assumed that HHI had developed an alternate method of communication to comply with flight-following requirements because a survey of some Gulf operators revealed that they had started using repeater aircraft or satellite telephones. However, HHI had not done so. In addition, the FAA principal maintenance inspector failed to inspect all of the company's PFDs (eight of which had unapproved repairs) and repairman's manuals (which were out of date). The FAA's inadequate surveillance of HHI's operations and maintenance over an extended time contributed to the persistence of an unsafe corporate culture at HHI, which led to a disregard for passenger briefings, improper handling of emergency situations, and lack of flight-following and fostered noncompliance with regulations.

Factual Information

HISTORY OF FLIGHT On September 6, 2005, about 1605 central daylight time (all times referenced in this report are central daylight time), the flight crew of a Sikorsky S-76A helicopter, N90421, registered to and operated by Houston Helicopters, Inc. (HHI), executed a forced landing into the open waters of the Gulf of Mexico about 24 miles southeast of Sabine Pass, Texas, after a loss of power to both engines. Both pilots and all 10 passengers were able to evacuate the helicopter before it submerged. All occupants wore personal flotation devices (PFD) to keep them afloat during the 7.5 hours that passed before they were rescued. (HHI's Operation Specifications [OpsSpec] require that crewmembers and passengers wear PFDs during flight.) Seven of the passengers sustained minor injuries, and three of the passengers and the captain and first officer sustained serious injuries. The on-demand air taxi flight was operating under the provisions of 14 Code of Federal Regulations (CFR) Part 135. Visual meteorological conditions prevailed at the time of the accident. The captain and first officer arrived at HHI's hangar in Pearland, Texas, about 0600 to begin duty. The pilots' first flight of the day departed about 0645. The accident flight was the 14th in a series of flights between various offshore oil rigs to provide scheduled crew changes for the Rowan Drilling Company. (At the time of the accident, the captain and first officer had been on duty for more than 10 hours and had completed 13 landings.) According to the accident pilots, the flight to the Bob Keller oil rig (the departure point for the accident flight) was uneventful. After landing, the first officer exited the helicopter to help deplane the passengers and then board the passengers for the accident flight to Sabine Pass, which was about 100 miles north of the oil rig. The accident flight departed about 1545. The first officer was the flying pilot, and the captain was performing the duties of the pilot monitoring. About 1603, as the helicopter was in cruise level flight, about 1,500 feet above the water, the pilots noticed that the Smoke Detector Baggage Warning light had illuminated. Subsequently, the No. 1 Engine Fire Warning light illuminated and tone alerted, and the captain took over control of the helicopter. Immediately thereafter, the No. 1 Engine Low Fuel Pressure and the No. 1 Engine Chip Detector Caution lights illuminated. The pilots stated that, at this time, they noted visible grayish-black smoke within the cockpit and passenger compartment areas. The captain stated that, as he turned the helicopter about 20 to 25 degrees to the north toward a nearby oil rig platform, the No. 1 engine lost all power. According to the cockpit voice recorder (CVR) transcript, at 1604:01, the captain instructed the first officer to lower the landing gear; the first officer complied with the captain's instruction. (The CVR was recovered from the helicopter before the wreckage was lost because of a hurricane.) Three seconds later, the first officer stated, "the floats are armed." Within 8 seconds, an engine out warning alerted. This was the first and only audible engine out alert on the CVR, although the captain indicated that both engines ceased to function before the helicopter crashed into the water. The captain stated that he entered the helicopter in an emergency autorotation to the surface of the water and then instructed the first officer to "get a mayday out." At 1604:29, the first officer transmitted the following on emergency frequency 121.5: "mayday, mayday, mayday, anyone on this frequency? This is Houston four two one." The CVR transcript indicated that, when asked to go ahead by the pilot of "aircraft 542" (a military aircraft flying near the helicopter at the time of the transmission), the first officer stated, "roger we're going in." The pilot of aircraft 542 asked the location of the helicopter twice, but each time, the first officer replied, "standby." The CVR recording ends 31 seconds after the mayday call. The captain stated that, when the helicopter was about 25 feet above the water, the main rotor blades stopped turning, and the helicopter descended vertically. Subsequently, the right side of the helicopter impacted the water in a nose-low attitude. Both pilots and the 10 passengers evacuated the helicopter before it completely submerged. The helicopter sank before the two emergency liferafts, which were stored under the first row of passenger outboard seats, could be removed by the crew and passengers. PERSONNEL INFORMATION Captain The captain, age 59, held an airline transport pilot (ATP) certificate with airplane single- and multiengine land ratings and commercial privileges for rotorcraft-helicopter. The captain held a first-class Federal Aviation Administration (FAA) airman medical certificate, dated December 9, 2004, with the limitation that he "must wear corrective lenses." The captain was hired by HHI in 1991 as a contract pilot to fly Bell 206 and S-76A helicopters. HHI records indicated that he qualified as a captain for the S-76A on May 15, 1992. HHI did not maintain a record of the dates or hours that the captain flew for the company. Pay stubs and expense report records revealed that the captain flew for HHI in November 2001, January and February 2002, June 2004, and August 2005. His most recent training record was dated 2001. A review of the captain's logbooks from January 1 to September 2, 2005, revealed that, during this period, he logged 263.5 total flight hours, 19.1 hours of which were in helicopters (all helicopter flights logged were local flights from/to the Pearland Heliport facility in the Gulf of Mexico) and 15.3 hours of which were in the S-76A (5.6 hours on July 19; 1.0 hour on July 29; and 8.7 hours on September 2, 2005). A search of the FAA's Enforcement Information System (EIS) revealed no records pertaining to the captain. A review of the captain's medical records did not reveal any noteworthy issues. The captain reported that he did not work in the 3 days before the day of the accident. He stated that he received at least 12, 12, and 10 hours of sleep on the fourth, third, and second nights, respectively, before the accident and about 7 hours of sleep the night before the accident. First Officer The first officer, age 51, was hired by HHI as a full-time employee on June 15, 2005. He held an ATP certificate with a helicopter-rotorcraft and instrument helicopter rating. The first officer held a second-class FAA airman medical certificate, dated November 1, 2004, with the limitation that he "must possess corrective lenses that correct for near and intermediate vision." According to HHI records, the first officer received flight training in the U.S. Army from 1983 to 1998. From 1998 to August 2004, he worked for DynCorp as a helicopter mechanic and an aviation instructor, and, from September 2004 to May 2005, he worked as a helicopter pilot for another Gulf of Mexico operator. He qualified as a second-in-command on the S-76A on July 14, 2005. According to HHI flight and duty time records from June 15 to August 23, 2005 (flight and duty time records were not provided for the remainder of August or September), the first officer received Part 135 training from June 15 to 17, 2005, and started completing flights on June 20. HHI records indicated that he accumulated about 29.1 total flight hours, 2.9 hours of which were in the accident helicopter. (He logged 4.4 hours of flight time in June, 19.7 hours in July, and 5.0 hours in August 2005). A search of the EIS revealed no records for the first officer. A search of the first officer's medical records revealed no noteworthy issues. The first officer reported that he did not work the second and third days before the accident. He stated that he worked as the radio dispatcher for HHI on the day before the accident from 0600 to 1700. He reported that, on the night before the accident, he attended an evening class at a local college and then went to bed no later than 2330. On the morning of the accident, he woke up about 0445. AIRCRAFT INFORMATION The accident helicopter was a Sikorsky Aircraft twin-engine, four-bladed, single-rotor helicopter. The helicopter was equipped with two Rolls Royce Allison gas turbine 250-C30S engines. The helicopter was certified to carry up to 13 passengers and 1 pilot under visual flight rules (VFR) and 12 passengers and two pilots under instrument flight rules (IFR) and had a maximum takeoff gross weight of 10,500 pounds. At the time of the accident, the estimated gross weight of the helicopter was 10,039 pounds. The helicopter was equipped with a caution advisory panel, which was mounted in the center of the flight instrument panel between the pilots, and two master caution warning panels, one of which was mounted in front of each pilot on the front instrument panel. When smoke in the baggage compartment is detected, the Smoke Det(ection) Baggage Warning light on the caution advisory panel illuminates, and the Master Caution Warning light on the two master warning panels also illuminates. When an engine fire is detected, the Engine Fire Warning lights illuminate; the light for the affected engine (which is on the T-handle located on the engine throttle quadrant above and in front of the pilots) illuminates and a continuous 250-Hertz aural tone alerts in both pilot headsets. According to the Sikorsky S-76A Flight Manual, the emergency procedures for responding to an engine compartment fire include pressing the Engine Fire Warning light (to reset the fire warning tone), establishing safe single-engine flight (76 knots), fully retarding the illuminated T-handle, and, if necessary, selecting and activating the fire extinguishing system. The pilots completed the first step of this procedure. The helicopter was equipped with a crew-activated flotation system designed to keep the helicopter upright and afloat for sufficient time to permit occupants to evacuate. When the helicopter impacted the water, the floats on the right side of the helicopter burst. METEROLOGICAL INFORMATION The closest official weather observation station was located at the Scholes International Airport, Galveston, Texas, located about 60 miles southwest of the accident site. On September 6, 2005, about 1652, an automated weather observation system reported, in part, the following: Wind, 080 degrees at 15 knots; visibility, 10 miles; ceiling and clouds, clear; temperature, 88 degrees Fahrenheit; dew point, 68 degrees Fahrenheit; altimeter, 30.05 inches of mercury. FLIGHT RECORDERS The helicopter was equipped with a CVR. The helicopter was not equipped, and was not required to be equipped, with a flight data recorder. WRECKAGE AND IMPACT INFORMATION According to the accident pilots, the helicopter impacted the water about 24 miles southeast of Sabine Pass. The helicopter wreckage subsequently sank in the Gulf of Mexico, in 40- to 50-feet deep water, with strong underwater current activity. An extensive underwater search effort was initiated, and the helicopter wreckage was subsequently located, and the CVR was recovered. However, an approaching hurricane in the area prevented the recovery of the helicopter wreckage. After the hurricane had passed, recovery crews returned to the last known site, but they were unable to locate the wreckage. SURVIVAL ASPECTS Safety Briefing The HHI Standard Operating Procedures Manual, dated 2005, states that all passengers must be briefed before flight on company aircraft. The manual also states that printed cards supplementing the briefing and applicable to the aircraft must be available to the passengers during flight. The briefing should be in accordance with 14 CFR 135.117, "Briefing of passengers before flight" [a] [6], which requires that, before each takeoff, the pilot ensure that all passengers have been orally briefed on ditching procedures and the location of required flotation equipment and that the oral briefing be supplemented with a printed card located in a convenient location for passenger use and contain instructions necessary for the use of emergency equipment on board the aircraft. The regulation also addresses, in part, seat belts, entry and emergency exits, and fire extinguishers and survival equipment. Although the first officer stated in postaccident interviews that he had asked the passengers if they had received a safety briefing and that they had replied, "yes," passengers stated in postaccident interviews that they did not receive a safety briefing before the accident flight. Occupant Evacuation During the impact with the water, the floats on the right side of the helicopter ruptured, and the helicopter rolled to the right and partially submerged. Both pilots and the 10 passengers evacuated the helicopter before it completely submerged. The last passenger to evacuate the cabin was almost entirely under water when he pulled himself through the left cabin doorway, which was facing skyward. Both pilots reported that the helicopter sank before they were able to remove the two emergency liferafts. Passengers reported that they did not know where the liferafts were located. Before each flight, HHI provided each pilot and passenger with a PFD, each of which is equipped with a rescue light. Eight of the passengers and the two pilots reported that their PFDs inflated when they pulled the inflation chord and that five of the PFD rescue lights illuminated and five of them did not illuminate. (Investigators were unable to contact two of the passengers despite numerous attempts to do so.) The occupants were in the water for 7.5 hours before they were rescued, and several of the passengers sustained hypothermia. Communications Regarding the Overdue Helicopter The pilots did not file a flight plan with the FAA, and no air traffic control (ATC) facilities in the accident area had any specific information about the helicopter or its operations in the Gulf of Mexico. However, a review of ATC communications from air traffic facilities in the area and situation reports and event logs from the U.S. Coast Guard (USCG) and the U.S. Air Force revealed that, from 1605 to 1620, numerous commercial and military flight crews reported that they heard a "mayday" transmission on emergency frequency 121.5. The flight crews reported that they did not have any information about the flight, including its tail number or location, because the information was not provided in the "mayday" transmission. Further, none of the reporting pilots were able to make contact with the flight. The only pertinent information about the distressed helicopter was provided by the pilot of Omaha 44, located 125 nautical miles northeast of Corpus Christi, Texas, who reported that he heard, "421. . .going in." About 1606, the Conroe Automated Flight Service Station (AFSS) in-flight controller relayed the information from the commercial flight transmissions to the San Angelo AFSS, Houston Air Route Traffic Control Center (ARTCC), and law enforcement agencies throughout southeastern Texas. About 1613, the Houston ARTCC provided this information to the Air Force Rescue Coordination Center (AFRCC), and the FAA Southwest Regional Operations Center (SW ROC). Further, the Polk County Sheriff Office was dispatched to the location of a possible incident about 30 miles south of Lufkin. About 1621, another flight crew advised the Houston ARTCC that they had heard "Houston 421" on the emergency frequency stating that he was "going in." Ten minutes later, the Houston ARTCC notified the SW ROC about a possible aircraft going down near Lufkin. About 1658, the Houston ARTCC was contacted by Navy Corpus Christi Base Operations on behalf of the flight crew of Omaha 44 to ask whether there was any closure on the "mayday" call. Houston ARTCC replied that there was still no confirmed position but that second-hand information indicated that the aircraft in distress might have been operating about 30 miles south of Lufkin. About 1749, the AFRCC contacted the Houston ARTCC to ensure that it was continuing to solicit information regarding the location of the distressed aircraft. About 1834, the owner of HHI called the Con

Probable Cause and Findings

The pilots' delayed response to the No. 1 engine fire warning and the loss of power to both engines, which occurred for undetermined reasons. The pilots' delayed response was most likely due to stress and fatigue. Contributing to the delay of the initiation of search and rescue operations were the pilots' incomplete "mayday" call, the pilots' and Houston Helicopter, Inc.'s (HHI's) noncompliance with company and Federal Aviation Administration (FAA) flight-following requirements, and HHI's inadequate communications contingencies and procedures for reporting overdue flights. Also contributing to the delay of search and rescue operations was the FAA's inadequate surveillance of previously identified company deficiencies, including HHI's lack of adequate flight-following procedures. This lack of surveillance allowed HHI's corporate culture to remain lax with regard to safety.

 

Source: NTSB Aviation Accident Database

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