Implications of Selected Airline CrashesBy Paulina E. Sikorska Published on: 7 March, 2014
Air transportation is without doubt the fastest method of moving from one place to another. Ironically, even if the topic of the essay is rather pessimistic, air transportation is currently the safest mode of transportation: the risk of passenger deaths is equal to one every 45 million flights.
However, the safety performance of air transportation strictly depends on which region we are talking about. In short, there are some huge discrepancies in aviation safety performance between developed countries and developing countries. Safety Information Analysis & Sharing [ASIAS], indicates that the ratio of US accident/ fatalities between 1991-1999 was “32/1,023” which decreased significantly in the next decade (2000-2011) to “11/518”.
The decreasing trend is not only the result of technological improvements, but mainly in my view due to the improvements in regulatory regimes dealing with aviation safety, which are sadly often implemented only after a fatal accident occurred. Firstly, this essay will discuss the International Civil Aviation Organization (ICAO) as a main aviation regulator at the international level, and then six case studies will be discussed before some conclusive points.
1) The role of the ICAO in overseeing aviation safety and regulating safety standards
The safety of civil aviation has become paramount for the International Civil Aviation Organisation as was reiterated in the ICAO 38th Assembly Resolution, in which the ICAO Technical Committee specifies five items that need to be discussed in relation to aviation safety: “policy, standardization, monitoring and analysis, implementation support”. Moreover, according to Professor Huang, “the safety standards found in the Chicago Convention are designed to enhance the global normative system for civil aviation”. Unfortunately, global system safety performance has not achieved a uniform level at which all the ICAO Member States would have the same safety standards applicable to air transportation.
Article 33 of the Chicago Convention sets out the minimum safety standards in aviation that every Member State has to obey. The penalties for negligent or deliberate breaches of the provisions include a ban from a particular country/counties air zone.
The European Union is a good example of an aviation safety guardian as it established the EU black list, which banned airlines that did not meet the minimum safety requirements as specified in Article 33 from flying into the European Air zone. This proved that we are far from having global unified aviation safety standards.
This essay will encompass three selected causes (the list is, by no means, an exclusive one) of plane crashes and indicates the preventive regulatory measures that were implemented as a result of each crash. It will start with accidents caused by weather conditions (limited here to accidents due to heavy rain, ice and wind), moving on to human factors including both situations where the procedures were in place, the pilot and crew members knew the procedures and they eventually omitted or breached the procedures which were in place, and where there were no procedures and flight crew members were not aware/ trained to perform. The last group of accidents is about technical failures, encompassing engine failures and the lack of smoke detectors in the cargo compartments.
2) Aviation accident case studies The three case study groups are tackled from the main probable cause perspective, as the elimination of main cause having a greater impact on the accident decreases the possibility of another one in the future. Hoekstra and Huang grouped the main causes and contributing factors as “pilot, weather, mechanical, personnel, terrain, airport and airway facilities”. In total there are six sources of significant danger affecting aviation safety; in the selected case studies, there is often a combination of two or more.
Bad weather conditions
In 1985, Delta Air Lines flight no 191 from Dallas/Fort Worth to Texas experienced severe rain conditions and was about to land in Texas. Unfortunately, the plane was affected by lighting and as a result the plane crashed and caught fire. Only 29 out of 163 people survived. It might be said that Delta could not predict acts of God and this is true. However, Delta was entirely capable of developing windshear detection technology which could prevent this kind of accident from occurring. According to NASA a strong change of wind (called windshear) adversely affects the aircraft's safety, thus in 1992 the NASA Langley Research Center worked on airborne technology which can detect windshear in advance.
In 1982, Air Florida flight no 90 from Washington, D.C to Fort Lauderdale, Florida experienced severe difficulties even before taking off; there was very poor visibility (less than a half mile), severe snow conditions and temperature below the freezing point.
The takeoff was unsuccessful, causing the death of 78 people. The National Transportation Safety Board (NSBA) report indicated several issues with the de-icing procedure, which can be summarized as follows. The first stage of a plane's de-icing procedure in the 1950s was mechanical and based on scratching ice from the wind. Developments in the 1960s allowed for more sophisticated and differing methods using a liquid composed of etyloglycen, propyloglycen and water. For example, the Trump manual proposes a ratio of “65% de-icing substance/35% water” as opposed to American Airlines, which opts for a ratio of “25% de-icing/75% water”.
The Report also suggests that the Air Florida Manual does not include any information about de-icing procedures. However, the report emphasizes that it is the role of the captain and cabin crew to ensure that the plane is prepared for departure.
In 2008, The FAA produced an in-depth document which imposed the International de-icing standards. In addition, the ICAO in cooperation with the major airlines published guidelines in 2008 specifying four mixture types for which usage depends on the temperature conditions and procedures which have to be put in place. This can be seen as a sign of uniformity. The only information which is not provided is the liquid/water ratio, so some airlines can still gamble with adding too much water.
In 1996, Valuejet flight no 592 departed from Miami, Florida to Atlanta. It crashed twelve miles from Miami in the Everglades shortly after takeoff. The NTSB confirmed the probable cause as an improperly stored oxygen generator marked as cargo. The failure was caused by SabreTech, which did not mark and pack the oxygen generator before being boarded on the Valuejet plane. The Valuejet itself is not blameless as did not obey maintenance practice regarding hazardous materials.
Finally, the FAA failed to force any airlines to install smoke detectors in the cargo compartment . The FAA made progress by producing a technical algorithm for dealing with the cargo compartment, where they showed not only one technology but four different fire detectors that can be used in the cargo compartment. As far as I understand, the chemical and physical processes explained in the report were used in different simulated situations and then the outcomes were compared with each other.
It has to be emphasized that in 1996 there were no fire detectors in any cargo compartments on the Valuejet plane and in 2008 there were four technologies competing with each other in order to maximize the safety performance. It is also important to note that nowadays the ICAO and the FAA produce guidelines on safety management systems regarding how to collect, analyze, share safety data and be sure of full implementation.
In 1974, Pan Am Airlines' flight no 806 from Auckland, New Zealand to Los Angeles, California crashed in Pago Pago during an unsuccessful attempt to land safely at the intermediate stop. As a result, all 97 passengers and crew died. The National Transportation Safety Board specified potential causes of the airplane crash, one of which was the failure of the cabin crew to discover and react to the excessive descent rate caused by “aircraft penetration through destabilizing wind changes".
The safety recommendations include additional monitored training for airline pilots during three takeoffs and landings, and an obligatory inspection of the safety guidelines content provided by the airlines in respect of their compatibility with the FAA guidelines and procedures. Masako Miyagi confirmed that pilot training and experience is crucial, especially in extraordinary situations during taking off or landing procedures.
I agree that practical training of pilots and cabin crew is a key point, as you may know all the procedural guidelines fairly well or even know by them by heart but in case of an unexpected event, or an event which is not anticipated in the particular manual, the faster one make a correct decision, the more likely the accident will be prevented. Analogically, one can read a book how to drive a car, pass a theory test and practice driving; nevertheless, when you are overtaking a car and you suddenly see the car from opposite side of the road, you have seconds to make a correct decision in order to avoid a collision. This works more like automatism, the automatism which a pilot has to learn by practising over and over again.
In 1996, TWA flight no 800 from New York, USA to Paris, France crashed several minutes after taking off, killing all 230 passengers on board. The NSTB confirmed the probable cause as an explosion of the center wing fuel tank, which occurred as a result of mixing fuel with air. The FAA immediately issued a recommendation for manufactures with regards to “bonding components inside fuel tanks in order to eliminate potential hazards of ignition”. Tank ignition guidelines in relation to aircraft are widely used not only by the FAA but also by the EASA , and the IATA is organizing courses on this subject.
In 1979, American Airlines flight no 191 from Chicago, Illinois to Los Angeles, California crashed shortly after taking off, killing all 285 passengers on board as well as people on the ground. According to the NSTB investigation report the main cause of the accident was a separation of the engine and the pylon before takeoff. As a result hydraulic system no. 1 was lost. Ironically, the pylon was damaged during the maintenance system of the aircraft in Oklahoma. The warning system stopped working, thus neither the cabin crew or the pilots could see the separation. According to Lenorovitz, before 1979 the same aircraft model experienced 11 engine fault incidents.
3) Overall safety performance in commercial aviation after crashes
According to the recent studies of the ICAO in its safety report of 2013 between 2006 and 2012, there was a decrease in commercial aviation fatal accidents from 806 to 372. North America achieved an excellent 0% in 2012 in respect to aviation fatalities compared to 33% in Europe. According to the AOPA 10 year trend in aviation the number of fatal accidents (per 100,000 hours) between 1994 and 2002 decreased by 24.7%.
The report includes statistics of airline crashes caused by the three causes pointed out earlier in the essay. Hence, beginning with weather conditions, the number of fatal accidents remained at the same level between 1994 and 2003 at 4-5% per 100,000 hours. Despite the fact that there is no significant decrease over a decade's time, it is important to emphasize that the quality of weather forecasting has improved and more attention is paid to pilot training. According to Boeing's studies of commercial aviation accidents , there were no accidents between 2002 and 2011 as a result of ice.
In respect of pilot and cabin crew mistakes, Shappel SA and others in the report on human errors in commercial aviation which resulted in fatal crashes proved that between 1990 and 2002 there were small ups and downs in the percentage of human factors, but it was higher in 1990 at 67% than in 2002 at 60%. However, in 1993 the result was 82%, followed by 75% in 1994. In 2001 the best result of 58% was achieved. What can be concluded is that human errors are the most difficult to eliminate as they cannot be easily removed, for example by using more advanced technologies like in the case of weather predictions or technical failures. Hopefully, both psychological and practical training as well as safety guidelines will help pilots and crew in making good decisions at the right time.
Finally, an engine failure diagram has been created which divides fatal accidents based on single engine and multiple engine incidents. The focus will be on multiple engines only as they were the subject of discussion earlier. Ironically, the lowest engine fault accident rate was in 1996 when the TWA no. 800 engine pylon separation occurred. 10% in 1996 raised dramatically to almost 60% one year later, then declined to 40% in 2000, rapidly rose to 100% in 2001 and finally reached 20% in 2003.
Taking everything into consideration, the optimistic point of disastrous crashes is that there have always been repercussions which have resulted in improved safety regulations in the industry. The other good point is that due to the volume of airline crashes there have been a lot of improvements and passengers in the developed countries can feel safe. The statistics in relation to accidents and technical failures look very promising and bearing in mind that the technologies are still developing, there could be a further decrease in accidents caused by technical failures. Human errors are the most difficult to eliminate to 0% as pilots or cabin crew cannot be 'programmed'.
Yes, they can be well trained and undertake different psychological and psychical tests, but one cannot predict the outcome of every situation, especially something extraordinary that can affect the flight. Nevertheless, practice makes perfect so at least better knowledge and preparation can reduce the magnitude of the risk of fatal crashes.
The final conclusion is that, in my view, aviation safety will become an emerging problem for developed countries, as the 2013 ICAO Safety Report indicates that the percentage of fatalities in air transportation in 2012 in Africa was over 45% compared to Europe, which had approximately 12%, and safety is indeed a challenge for developing countries.
The reasons for this could include a lack of sufficient funds for new aircraft and using old ones that would never pass the airworthiness test in developed counties, poor pilot and cabin crew training, and noncompliance with the ICAO safety rules. Thus, attention concerning safety standards in aviation will be focused on developing countries, where using air transportation could still be described as another kind of extreme sport.
References for the above article are available on request.
Article picture: First public demonstration in Annonay, 4 June 1783 of a balloon flight by the Montgolfier brothers.
of the Week
Lincoln’s Code: The Puzzling History of the Laws of War. John Fabian Witt, Allen H. Duffy Class of 1960 Professor of Law, Inaugural Lecture.
Tip: Suggest a video!