Aircraft accidents

In general, tlie carriage of hazardous materials does not appear to be a significant cause of, or aggravating factor in, aircraft accidents. However, improperly packed and loaded nitric acid was declared tlie probable cause of a cargo jet crash at Boston in 1973, in which tliree crewmen died,"... 

Betti reported on the civil use of depleted uranium and various relevant scenarios (e.g., the case of an aircraft accident which occurred in Amsterdam in 1992 involving a fire) in terms of radiological exposure to bystanders.62... 

The site should be outside the landing and takeoff patterns of an airport to minimize exposure to aircraft accidents. 

National Transportation Safety Board (NTSB) (1991), Aircraft Accident Report Avianca, the Airline of Columbia, Boeing 707-321B, HK 2016 Fuel Exhaustion, Cove Neck, New York, January 25, 1990, Report No. NTSB-AAR-91-04, NTSB, Washington, DC. 

It is interesting to note that in the United Kingdom, 1 ton of steel is converted into oxide rust every 90 s. Apart from the wastage of metal, the energy required to produce 1 ton of steel from iron ore is equal to the energy requirement of a family for 3 months. The international opinion of the Exxon Valdez spillage in Alaska and that of an aircraft accident did not prevent Braer oil tanker spillage. Pollution is still allowed to happen because of the improper attitudes and lack of international action. 

It is still common to see statements that 70 percent to 80 percent of aircraft accidents are caused by pilot error or that 85 percent of work accidents are due to unsafe acts by workers rather than unsafe conditions. However, closer examination shows that the data may be biased and incomplete the less that is known about an accident, the most likely it will be attributed to operator error [93]. Thorough investigation of serious accidents almost invariably finds other factors. 

This case, however, does not seem to have had much impact on the attribution of pilot error in later aircraft accidents. 

John Shalikashvili, chairman of the Joint Chief of Staff, from a cover letter to the twenty-one-volume report of the Aircraft Accident Investigation Board, 1994a, page 1. 

Figure 7.2 shows the high-level requirements and constraints for some of the air traffic control hazards identified above. Comparing the ATC high-level constraints with the TCAS high-level constraints (figure 7.3) is instructive. Ground-based air traffic control has additional requirements and constraints related to aspects of the collision problem that TCAS cannot handle alone, as well as other hazards and potential aircraft accidents that it must control. 

A more complex example occurred in what is believed to be a cause of an A320 aircraft accident. The crew directed the automated system to fly in the track/flight PATH ANGLE mode, wWch is a combined mode related to both lateral (track) and vertical (flight path angle) navigation ... 

Aircraft Accident Investigation Commission. Aircraft Accident Investigation Report 96-5. Ministry of... 

James G. Andrus. Aircraft Accident Investigation Board Report US. Army UH-60 Black Hawk Helicopters 87-26000 and 88-26060. Department of Defense, July 13,1994. 

Bundesstelle fiir Hugunfalluntersuchung. Investigation Report. German Federal Bureau of Aircraft Accidents Investigation, May 2004. 

Main Commission Aircraft Accident Investigation Warsaw. Report on the Accident to Airbus A320-211 Aircraft in Warsaw, September 1993. 

Conventional structures, such as a bridge or a civil aircraft, are still commonly passive structures. These structures are designed to withstand the maximum expected loads, even in the presence of small cracks that may occur in service, due to corrosion, impacts with external objects or any other reason. The maximum crack size before catastrophic failure can be predicted, and the detectable crack size (of course, much smaller than the critical size), are defined according to the available non-destructive methods also the crack growth by dynamic loads can be predicted. Therefore, the time between inspections can be defined to avoid any incipient but undetected crack to become critical. This is the so called maintenance on schedule , and it has proven to be a very safe method - presently the percentage of aircraft accidents due to structural failure is very low. But the cost of these inspections is high, because they require sophisticated NDl and many labour hours. The cost of maintenance is about a quarter of the total life-cycle costs of an aircraft, similar to the fuel, crew, or acquisition costs. 

At the same time, the FAA has refused to establish a mandatory retirement age for flight engineers. While a flight engineer has important dnties which contribute to the safe operation of the airplane, he or she may not assnme the responsibilities of the pilot in command. 49 Fed.Reg., at 14694. Moreover, available statistics establish that flight engineers have rarely been a contribnting cause or factor in commercial aircraft accidents or incidents. Ibid. 

It is broadly accepted that the prime causal factors of an aircraft accidents are either ... 

Note Sometimes data are valid only in special circumstances. For instance, a statistical sourcemay indicate that a specific number of aircraft accidents due to bird strikes take place every 100,000 hours. One may conclude from this data that the probability of a bird strike is comparatively low. Hidden by the data analysis proach is the fact that at certain airfields, such as Boston, the Midway Islands and other coastal and insular areas where birds abound, the probability of a bird strike accident is much higher fiian file average. This example demonstrates that generalized probabilities will not serve well for specific, localized areas. This applies to other environmental hazards such as lightning, fog, rain, snow and hurricanes. 

Human errors continue to dominate as a contributing factor in aircraft accidents (see Annex A to this chapter). A Boeing study (2001) found that flight crew errors are listed as the primary cause in 66% of accidents and that despite the introduction of protective devices or systans, this percentage has remained relatively unchanged in recent years. An FAA study (2002) into Aeroplane Safety Assurance Processes concluded that the processes used to determine and vahdate human responses to failure and methods to include human responses in safety assessments need to be improved and that the industry challenge is to develop aeroplanes and procedures that are less likely to result in operator error and that are more tolerant to operator error when they do occur . 

No discussion of aew error is complete without considering the hazard Loss of Situational Awareness , which studies have shown to be a leading causal factor in a review of 175 military aviation nfishaps (Hartel et al., 1991) and a major causal factor in 88% of accidents associated with human error in a review of major aircraft accidents between 1989 and 1992 (Endsley, 2001). 

Eor low dispersible material the airborne release of radioactive material in gaseous or particulate form is limited to 100 A2 when subjecting the contents of a Type B(U) package to the mechanical and thermal tests. This 100 limit refers to all particle sizes up to 100 pm AED. Airborne releases can lead to radiation exposure of persons in the downwind direction from the location of an aircraft accident via several exposure pathways. Of primary concern is a short term intake of radioactive... 

The duration of the fire test for air accident qualification was set at 60 min. Statistical data on fires resulting from air accidents support the conclusion that the 60 min thermal test exceeds most severe fire environments that a package would be likely to encounter in an aircraft accident. Fire duration statistics are frequently biased by the duration of burning of ground structures and other features not related to the aircraft wreckage, as well as by the location of consignments involved in the accident. To account for this effect, information on fire duration was evaluated carefully to avoid bias by accounts of fires that did not involve the aircraft. The fire test has the same characteristics as those specified in para. 728. 

Potentially the most severe accident environment for many Type A packages is the combination of severe mechanical damage with a fire. However, even in this situation the role of debris may be significant in retaining released radioactive material, as appeared to have happened in the 1979 DCS aircraft accident in Athens [1.21,1.22]. 

Unlike water, fire is less a concern with adhesives than with composites. However, flame-resistant adhesives have potential applications in aircraft interior panel structure. In the last two years, some tragic civilian aircraft accidents have prompted the development of flame-resistant adhesives. 

National Transportation Safety Board (1980), Downeast Airlines, Inc., DeHavilland DHC-6-200, N68DE, Rockland, Maine, May 30,1979, Aircraft Accident Report Number NTSB-AAR-80-05. 

All U.S. civil aviation accidents and certain public-use aircraft accidents Selected highway accidents... 

Wood, Richard and Robert Sweginnis, Aircraft Accident Investigation, 2nd ed.. Endeavor Books, 2006. 

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