Risks of Methane Venting
The U.S. National Transportation Safety Board (NTSB), citing two cases of engine power loss on turbine helicopters operating to and from oil platforms in the Gulf of Mexico, is calling for action to mitigate the risks of the nearby discharge of methane and other raw gases.
The NTSB said that, in both accidents, the loss of engine power probably resulted from “inadvertent ingestion of methane gas that was being vented in the vicinity.”
The first accident, on March 24, 2011, involved a Bell 206-L3 that experienced a partial power loss after takeoff from an oil production platform. As the helicopter passed above an “exhaust pipe” on the platform, the pilot and passengers heard a loud bang, and the helicopter subsequently struck the water and rolled. The three people in the helicopter received minor injuries, and the helicopter was substantially damaged.
Investigators said there was no visual indication to inform pilots when the pipe was in use, and the accident pilot said that, although he had seen the pipe, he did not know what it vented and could not tell it was in use. The NTSB said the probable cause of the accident was the “loss of engine power due to an engine compressor stall as a result of ingesting methane gas during takeoff.”
The second accident, on Aug. 13, 2013, involved a Bell 207 that lost all engine power after takeoff from a different oil production platform. The pilot heard a loud bang and the helicopter struck the water. The pilot and both passengers received minor injuries; the helicopter was substantially damaged.
The NTSB investigation was continuing, but preliminary information indicated that the platform had no system to indicate to pilots when venting was in progress.
As a result of its investigations, the NTSB recommended that the U.S. Interior Department and the U.S. Coast Guard develop systems and procedures to mitigate the risk that methane and other discharged raw gases will be ingested by helicopters operating near the platforms, and that the systems and procedures be implemented. A recommendation to the American Petroleum Institute calls for revision of institute guidelines for offshore platform design and construction to address the venting of raw gases.
The European Aviation Safety Agency (EASA) is pressing for development of a European approach to a performance-based environment (PBE) to improve the management of aviation safety.
EASA defines PBE as “an environment based on safety performance indicators on which safety assurance and promotion, as well as performance-based regulation [PBR] and performance-based oversight, can be built.”
A PBE that emphasizes risk management is needed because of the increasing complexity of the aviation system, EASA said in a report issued in late August. The document noted that a PBE provides the framework for establishing clear goals and establishes safety performance indicators (SPIs) to measure trends, obtain feedback and determine methods of meeting goals.
“SPIs can be qualitative, quantitative, absolute or relative, and they must be supported by the systematic collection and analysis of data,” the report said. “In relation to safety, this data can be obtained from sources such as questionnaires/surveys, occurrence reports, technical reports (reliability, observation and data-capturing systems such as flight data monitoring), operational performance monitoring systems, oversight and inspection activities and, more generally, data on areas such as economics, social and organisational information.”
The report said that, although prescriptive rules and associated oversight have succeeded in reducing the rate of passenger fatalities, PBR offers new advantages such as an improved focus on performance improvements and improved understanding of risk mitigation.
“A PBE improves the overall quality of rules and safety oversight,” the report said. “Instead of establishing prescriptive regulations telling individuals and businesses what they can and cannot do, PBR sets goals for the desired outcomes (safety objectives) and measures performance against them.”
Searching for Flight 370
The search for the missing Malaysia Airlines Boeing 777-ER has shifted to what the Australian Transport Safety Bureau (ATSB) describes as a “long but narrow arc” in the southern Indian Ocean, where investigators are focusing on mapping the ocean floor.
“The complexities of the search cannot be understated,” said the ATSB, which is leading the search at the request of the Malaysian government. “Our work will continue to be thorough and methodical, so sometimes weekly progress may seem slow.”
The agency said the first step in the current effort is a bathymetric survey, which involves measuring the ocean’s depth in order to develop a map that can depict the “contours, depths and hardness of the ocean floor.”
The mapping process includes the use of multibeam sonar, which calculates depth by measuring the time sound waves take to travel from the ship to the ocean floor. Unlike single-beam sonar, which maps one point beneath the ship, multibeam sonar uses multiple beams and measures a wider area. The speed at which sound travels depends in part on the salinity, temperature and depth of the water, the ATSB said, “and noting that these change throughout a water column, signals are corrected.”
When the mapping is complete, map information will be used to aid a search of the ocean floor, to be conducted with scanning equipment or submersible vehicles, the ATSB said.
Flight 370, with 227 passengers and 12 crewmembers, disappeared on March 8 during a scheduled flight from Kuala Lumpur, Malaysia, to Beijing. The flight crew’s last contact with air traffic control came less than an hour after takeoff. Accident investigators believe that the airplane flew for several more hours, eventually entering the water in the southern Indian Ocean.
The International Civil Aviation Organization (ICAO) says a task force is investigating how the notices to airmen (NOTAM) system could be used to disseminate urgent information about flights above areas of armed conflict.
The Task Force on Risks to Civil Aviation Arising From Conflict Zones (TF RCZ) said after a late August meeting that it also would consider a new centralized system for sharing the information.
“These recommendations will help to ensure the safety of civilian passengers and crew, no matter what airline they are flying on or where they are flying,” said TF RCZ Chairman David McMillan, who also is the chairman of Flight Safety Foundation’s Board of Governors.
The task force was convened in the aftermath of the July 17 downing of a Malaysia Airlines Boeing 777 over eastern Ukraine. All 298 people in the airplane were killed, and the airplane was destroyed in the crash. Investigators say the 777 was struck by a missile as it flew over an area where pro-Russian separatists had been fighting Ukrainian government forces.
The task force’s preliminary findings will be delivered in October to the 203rd session of the ICAO Council, and the task force has scheduled further discussions in December.
Unstable-Approach Mitigation Plan
The Transportation Safety Board of Canada (TSB) says it will take time to assess the effectiveness of Transport Canada’s (TC’s) response to a TSB safety recommendation intended to reduce the number of unstable approaches that are continued to a landing.
The TSB issued its recommendation as a result of its investigation of the Aug. 20, 2011, controlled-flight-into-terrain crash of a Boeing 737 in Resolute Bay, Nunavut. Eight passengers and all four crewmembers were killed in the crash, and three passengers were seriously injured; the airplane was destroyed.
“In this accident, the aircraft arrived high and fast on final approach, was not configured for landing on a timely basis, had not intercepted the localizer and was diverging to the right,” the TSB said. “This approach was not considered stabilized … and the situation required a go-around. Instead, the approach was continued.”
The flight crew began a go-around only after it was too late to avoid the crash, the TSB said.
In its safety recommendation, the TSB said that TC should require the operators of large commercial aircraft (those operated under Canadian Aviation Regulations Subpart 705) to “monitor and reduce the incidence of unstable approaches that continue to a landing.”
TC’s response took the form of a civil aviation safety alert calling on Subpart 705 operators to use their safety management systems (SMS) to identify situations in which unstable approaches occur and to develop plans for mitigation. The plan calls for a follow-up program beginning in June 2015 to determine what actions have been taken.
“Although TC’s safety alert is a positive step, it will be some time before the effectiveness of this voluntary approach can be validated,” said TSB Chair Kathy Fox. The TSB added that Subpart 705 operators have had SMS for several years, but the systems have not effectively addressed the problem of unstable approaches.
British Airways faces a possible $195,000 civil penalty proposed by the U.S. Federal Aviation Administration (FAA) for an alleged violation of hazardous materials regulations.
The FAA says that in August 2012, the airline gave American Airlines “a cardboard box containing a chemical oxygen generator for shipment aboard a passenger aircraft” from London to Dallas. “Oxygen generators are extremely flammable and are forbidden as cargo aboard passenger aircraft,” the FAA said, adding that the generator — a part of the passenger oxygen system — was being sent to Texas for repairs.
British Airways did not declare the hazardous material and did not provide required packaging, labeling or emergency response information, the FAA said.
The FAA proposed smaller civil penalties against three other firms — FedEx, Linvin and Allied Technology Group — that it also accused of violating hazardous materials regulations. All four companies have either requested or scheduled meetings with the FAA to discuss the matter.
In Other News …
The U.S. Federal Aviation Administration (FAA) is seeking public comments on draft Advisory Circular (AC) 120-66C, Aviation Safety Action Program (ASAP), which clarifies FAA policies on ASAP, designed for voluntary reporting of safety concerns by air carrier and repair station employees. Comments will be accepted through Nov. 4. More information is available at <www.faa.gov/aircraft/draft_docs/afs_ac>. … The U.K. Civil Aviation Authority (CAA) says that it may ask pilots who infringe on controlled or restricted airspace to take an online test to evaluate their airmanship. Under the policy, which took effect in September, the test is part of an effort to reduce airspace infringement, the CAA said.
Macarthur Job … Australian pilot, aviation safety consultant and author Macarthur Job, the first full-time editor of Aviation Safety Digest, the safety publication of the Australian Department of Civil Aviation’s Air Safety Investigation Branch, died Aug. 6 at age 88. Job “established a lasting legacy in promoting aviation safety in Australia,” the Australian Transport Safety Bureau said.
Compiled and edited by Linda Werfelman.