How The NTSB Investigates Aviation Accidents
When there is a civil aviation accident in the United States, the National Transportation Safety Board is responsible for investigating it. But what exactly is the National Transportation Safety Board (NTSB), and what does it do?
The NTSB was created in 1967 and is an independent organization from the U.S. government, with no regulatory or enforcement powers. Its primary purpose is to promote safety in transportation and is responsible for investigating not only all civil aviation and certain public aviation accidents, but also accidents involving highway, marine, pipelines and railroads. Since its inception, the NTSB has investigated 132,000 aviation accidents.
NTSB Go Team Investigations
With each aviation accident investigation, the NTSB first forms what it calls a "Go Team." Each team has between three and a dozen or so specialists from the organization's Washington, D.C.'s headquarters and its regional offices throughout the United Sates, and is dispatched quickly to the scene of the accident.
Each Go Team is led by an experienced, senior NTSB veteran, called the Investigator-in-Charge.
Aviation Accident Areas of Investigation
The NTSB examines each aviation accident following a set of specific factors and possible contributing causes:
- OPERATIONS: The history of the accident flight and crewmembers' duties for as many days prior to the crash as appears relevant.
- STRUCTURES: Documentation of the airframe wreckage and the accident scene, including calculation of impact angles to help determine the plane's pre-impact course and attitude.
- POWERPLANTS: Examination of engines (and propellers) and engine accessories.
- SYSTEMS: Study of components of the plane's hydraulic, electrical, pneumatic and associated systems, together with instruments and elements of the flight control system.
- AIR TRAFFIC CONTROL: Reconstruction of the air traffic services given the plane, including acquisition of ATC radar data and transcripts of controller-pilot radio transmissions.
- WEATHER: Gathering of all pertinent weather data from the National Weather Service, and sometimes from local TV stations, for a broad area around the accident scene.
- HUMAN PERFORMANCE: Study of crew performance and all before-the-accident factors that might be involved in human error, including fatigue, medication, alcohol. Drugs, medical histories, training, workload, equipment design and work environment.
- SURVIVAL FACTORS: Documentation of impact forces and injuries, evacuation, community emergency planning and all crash-fire-rescue efforts
The NTSB forms a working group for each of these areas, which include NTSB investigators and representatives of the Federal Aviation Administration, the airline, the engine manufacturer and other interested parties. The working groups remain at the accident scene as long as necessary to complete their fact and data-gathering mission; anywhere from a few days to weeks. Many of the groups then move on to continue their work at the NTBS headquarters, including flight data and cockpit voice recorder teams.
Ultimately, the groups' work is included in a report draft that is sent to the NTSB. The process typically takes between 12 and 18 months from the date of the accident.
After the full investigation is concluded, NTSB headquarters releases a final report. It contains a conclusion as to the accident's probable causes, and safety recommendations related to the accident. The report is placed on the organization's website (ntsb.gov), on the "Publications" page.
While the NTSB probable cause reports are available online, they are not admissible as evidence in aviation accident lawsuits. Plaintiffs in such litigation must prove the cause of the accidents without the NTSB reports. Investigations outside of the NTSB, therefore, require a team of qualified, experienced aviation experts.