Crash investigations focus on ‘Why’, and not ‘Whodunnit’
- 21/03/201928/10/2019
- by Dan Odido
An accident investigation hearing is conducted by non-flying experts who need six months to itemize all the mistakes made by a crew in the six minutes it had to do anything. – Anonymous
Aviation does not waste any crisis…
The aviation industry does not waste any aircraft accident or serious incident.
Every aviation accident or serious incident provides an opportunity to learn from gaps in operating procedures or technology. It provokes improvement within the whole industry, with the result that aviation has become the safest mode of transportation. Global aviation regulator, International Civil Aviation Organisation, ICAO has already proposed some recommendations in the wake of the baffling disappearance of Malaysia Airlines Flight MH 370. It proposes the introduction of a global system for tracking airliners. There is also a suggestion to extend the duration of cockpit voice recorders to 25 hours from the current 2 hours.
Accident investigation is carried out in accordance with Annex 13 of the Chicago Convention (Annex 13 – Aircraft Accident and Incident Investigation).
Crash investigations focus on the ‘why’, not ‘who’s fault’
The objective of the investigation of an accident or serious incident is to prevent future accidents and incidents, and not to apportion blame or liability. The issue of liability does however rear its head in indemnity claims for victims, especially if blatant negligence or technical fault is demonstrated.
Responsibility for accident investigation
Annex 13 indicates the States which may participate in an investigation. The State in which the accident or serious incident occurs has the first precedence in responsibility for carrying out the investigation. It may however delegate part or all of the investigation to another State. The State in which the accident occurs also takes all reasonable measures to protect the evidence and to maintain safe custody of the aircraft and its contents during the investigation.
In some cases the accident occurs in a location that is not within the territory of any State. The State in which the aircraft is registered conducts the investigation in such a case. It may also delegate this responsibility. This may sometimes lead to dispute.
A Boeing 767 that was operating as EgyptAir Flight 990 on a scheduled flight from Los Angeles to Cairo crashed into the Atlantic Ocean killing all 217 on board in 1999 . The onus was on Egyptian Civil Aviation Authority, ECAA to investigate the accident. It however handed the investigation over to USA’s National Transportation Safety Board, NTSB since it lacked the required resources to salvage the aircraft. ECAA backtracked two weeks later when NTSB invited the FBI, arguing that the evidence suggested an intentional criminal act. The two organisations subsequently carried out parallel investigations. ECAA ended up attributing the crash to mechanical failure while NTSB blamed intentional actions of the First Officer.
Other interested parties
The State of Registry; the State of Operator; and the State of Design and Manufacture of the Airframe and the Engine are each entitled to appoint accredited representatives to participate in the investigation. States whose citizens have suffered fatalities are also entitled to appoint an expert to participate in the investigation. The International Civil Aviation Organisation, ICAO is informed of accidents that involve aircraft of a maximum mass of over 2,250 kg.
See also: Suspicion and strife strain Ethiopian plane crash probe
The investigators produce a preliminary report within the first month. ICAO recommends that investigations be completed within one year. In case this is not possible, an interim report is issued on the first anniversary of the accident. Progress reports are made in subsequent anniversaries. A copy of the Final Report into the investigation into an accident or an incident involving an aircraft of a maximum mass of over 5,700 kg is sent to ICAO. Accident investigations can take a long time, and duration of five years is not unusual.
Evolution of Flight Safety
Safety in aviation has evolved over the years. The industry recorded the first aeroplane crash in 1908. This occurred when a propeller broke in a demonstration flight of the Wright Military Flyer that was being flown by Orville Wright. The accident resulted in one fatality.
Technical faults were common in the early years of the industry. The series of accidents that dogged the first jet airliner, de Havilland Comet was characteristic of this era. These initially unfathomable Comet accidents laid the foundation for introduction of aircraft accident investigation techniques and technologies that are still used to date. One of these is the deployment of the ‘black box’ (Flight Data Recorder and Cockpit Voice Recorder) in aircraft with the express purpose of post-crash examination. These are now deployed in all modern airliners.
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The contribution of human factors to aircraft accidents became predominant as the technology matured and technical faults were rectified. Human error is currently cited as the leading cause of most accidents. Pilot error contributes the largest portion. Organisational issues have also taken on a big share of accident causes in the present time.
No single cause: The Swiss cheese Model
Accidents are generally caused by several factors, and do not result from a single fault point. The aviation system is a complex productive system that involves interaction of man and machines. Most aircraft systems utilise redundant design, meaning that a single failure is unlikely to lead to an accident, or even an incident; engines, control and other vital systems are usually duplicated.
Prof. James Reason proposed a model that is often used to understand the dynamics of the interaction between man and technology. This is now popularly referred to as ‘Reason’s model’, or the ‘Swiss cheese model’. The model identifies two types of failure. Active failures occur at the operational level. An example is the type of errors made by the pilot, mechanic or air traffic controller. The second type of error is referred to as ‘latent failures’. These failures result from decisions made far removed in time and space. Examples are the organisational culture.
Accident investigations will typically identify several causes, both active and latent. These are subsequently communicated to the rest of the industry to avoid recurrence due to a similar cause.
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Dominance of pilot error as the cause of accidents
Pilot error is cited for 50% of accidents in aviation. This does not in any way mean that aircraft pilots are a particularly careless group of professionals! On the contrary, it demonstrates the extremely high level of professional competence expected from them. They are the last line of defence, and are supposed to be able to contain all other errors made elsewhere along the chain and redeem a deteriorating situation. This may still seem unfair, since the pilots often have a short time to respond to a rapidly evolving emergency. Investigators after the fact have all the time to analyse and theorise on what could have been done differently.
Spectacular demonstration of airmanship by some pilots
Several pilots have acquitted themselves spectacularly in emergencies. Some of these cases have gone on to become part of the aviation ‘folklore’. A few examples will suffice.
In US Airways Flight 1549 Capt. Sullenberger successfully ditched (i.e. landed in water) an Airbus A320 in 2009 following failure of all engines. The engines flamed out as a result of striking a flock of large geese shortly after takeoff. This was subsequently referred to as the ‘Splashdown on the Hudson’.
Another celebrated case is Air Canada Flight 143. In this case Capt. Pearson was able to successfully glide and land a Boeing 767-200 that had run out of fuel at altitude of 26,000 feet! The aircraft safely landed in a disused airfield. The event received the nickname ‘the Gimli Glider’ from the location of the airfield in Gimli, Manitoba.
The investigators recommended changes in operating procedures to avert similar challenges the future In both these cases .
Modern aeroplanes excessively ‘computerised’
Modern aircraft design greatly relies on computerised automation. Several industry players have voiced concerns that the highly automated aircraft are leading to loss of ‘airmanship’ skills among pilots, who are reduced to little more than ‘computer minders’.
One result is the increase in aircraft-pilot coupling problems. Operations of computerised systems are not always transparent to the flight crew. Findings from the investigation of Air France Flight 447 highlighted the role of the interaction between the pilot and the flight computer that was operating at an alternate law at high altitude. The importance of airmanship is poignantly demonstrated in the case of the Gimli Glider where Capt. Pearson was able manually glide a large aircraft. This was in no little measure due to the skills he obtained and honed as a hobbyist glider pilot in his free time away from the airline work.
Concern over new technology
Use of new technology raises other concerns. Passengers are understandably interested in their rights as regards their safety during flight despite the overriding objective of determining the cause of an accident for purposes of future safety. Airlines owe reasonable duty to passengers to operate safely and to utilise airworthy aircraft that are properly maintained and inspected. They are also expected to employ personnel who are qualified and well trained.
New technology is generally safer, more efficient and environmentally friendly. Its introduction however sometimes comes with teething problems and hiccups. Any new implementation comes with risk, and manufacturers are cautious to make changes to their designs that have historically functioned well. This can lead to stagnation.
See also: The Boeing 737 Max 8 – Taking no chances with technology
General Aviation (private air transport) has been particularly hard hit by stagnation. Litigation involving product liability is largely blamed for the decline of this branch of aviation. Manufacturers face risks associated with design defect, manufacturing defect and failure to warn on the correct use of the product. They are therefore shy to introduce new aircraft. Upto US $100,000 of the price of a new private aeroplane covers potential liability insurance since 90% of crashes of this category of aircraft result in product liability actions against the manufacturer.
Compensation for victims
Compensation for victims of aircraft accidents in Commercial Aviation is relatively straightforward in most typical cases. The rights of passengers in international flights are governed by the Montreal Convention of 1999. It stipulates that affected passengers get a maximum value equal to 113,100 Special Drawing Rights if the airline is not proved to be negligent. This is currently equivalent to US$170,000. The figure is unlimited if it can is shown that the airline did not take all the required precautions for a flight. Several airlines have ceased operations as the result of an accident.
Airlines underwrite their aviation risks by using a number of insurers. The payout for victims depends on the liability determined. Indemnity claims may also be made against the manufacturer or the maintenance company.
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Dan Odido is an aeronautical engineer and a university lecturer. He has been Head of the Departments of Flying Studies ; and Aerospace Security and Logistics in the School of Aerospace Sciences of Moi University in Kenya.