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Reflections on commercial air transport safety in the jet era

Kauffman C.

Research Bulletin / Warsaw University of Technology, Institute of Aeronautics and Applied Mechanics

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2000

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nr 10

15-32

EN

The commercial air transport industry is growing with the current approximately 14,000 aircraft expected to double in number by 2018. Unless the current basic accident rate (0.2 per 100,000 hours) is decreased it is anticipated that there will be a major air disaster with this large number of planes approximately every two weeks, a clearly unacceptable situation. If accidents are examined beginning with the decade of the 1960's through the present, certain common causes may be identified and the corrective measures implemented in order to address the problem. Midair collisions occurred but TCAS was introduced with great success. However, the collision problem is feared now to have shifted to the ground - on the runways, taxiways, and aprons, and they are now called incursions. This is one of the NTSB's most wanted solutions for a problem. Ground control radar must be widely introduced and employed to prevent these on-the-ground collisions. Windshear and microbursts caused many aircraft to impact the ground, but doppler radar, the proper observation of airspeed, and appropriate aircraft maneuvering have caused a decrease in this type of accident. Controlled flight into the terrain has been the cause of the largest number of disasters. However, the introduction of GPWS and its enhanced version has had a significant effect in decreasing the numbers of these types of accidents. Aircraft icing led to the smallest number of crashes, but it seems to be a problem which continues even though there is general awareness of its adverse potential. It too remains on the NTSB's most wanted list. For all of these causes of aviation disasters, the problem was identified, and with the exception of incursions and icing, solutions or remedies with very good effects have been found. However, a new class of causes for accidents which are much more insidious have been appearing within the last decade or two. Accidents are seemingly becoming more complex and/or more unanticipated due to the appearance of the "unk unks" or unknown unknowns. While it has always been known that fuel tanks often contained explosive vapors (-30% of the time), it was considered possible to eliminate all ignition sources. After over a dozen accidents involving both civilian and military aircraft a study is being made relating to fuel tank inerting - the last item on the NTSB aircraft safety wish list. There have been other disasters which have resulted from aircraft age (aircraft currently in service may be well over 20 years old). Additional accidents have resulted from aircraft design defects which remained undetected for many years. Onboard fires usually produce disastrous effects and may begin in unanticipated ways. Information which is displayed to the crew may be misleading or be misinterpreted, thus causing a crash. Intentional, inappropriate crew had behavior which has almost been dismissed out-of-hand has been implicated in five recent catastrophes. With these latter classes of accidents, it may be asked what technological fixes may be made. It may not be so simple. Solutions may be generated if the financial penalties which must be paid as a consequence of aviation disasters are significant. Currently, worldwide, the aviation industry pays $1.3 billion in insurance premiums. With proper investment perhaps this might be increased to $1.68 billion. Recently, to a survivor of the American Airlines, Little Rock, Arkansas landing accident, $11 million was paid. Hence, about 118 such awards could be made each year. On the average there are about 1000 fatalities each year. In such a situation the insurance rates must increase, the number of accidents will need to decrease, or an artificial limit must be imposed onto the financial compensation awards (tort reform?). While statistically air travel is safer than other choices, when disasters do occur they are totally destructive and abhorrent, A renewed effort must be made to futher reduce the accident rates by identifying and controlling the remaining difficult factors.

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Viewnet-virtual interactive east west network for engineering and technology an electronic tool for global enginnering

Kauffman C., King H., Shaland I., Spurlock O., Ziegler H.

Research Bulletin / Warsaw University of Technology, Institute of Aeronautics and Applied Mechanics

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1999

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nr 9

39-40

EN

Digital information, fiberoptics, and telecommunications satellites are making it possible to implement the concept of the global village. The sector is responding to this opportunity in virtual laboratories, virtual product development teams, and virtual factories where individuals and facilities which are remotely located are linked for the common good as well as the task at hand even allowing a continual effort to be on a project as the work day moves around the globe. Eventually this situation will also be recognised by the academic community and knowledge will be transferred between libraries, and students instantly between locations on the globe. Through the Internet such possibilities are now being initiated. However, it will be the long term commitment of the private sector to the concepts of telecommuting, remote distance and digital libraries which will ensure its The termination of the Cold War has conditions allowing the implementation of concepts. Economic conditions currently within the United States are quite robust to an acute shortage of qualified experts. In and Central Europe employment levels are not as high while in the Republics of the Former Union large numbers of trained experts are employment. Consideration may also be to other areas of the globe such as the Pacific Rim, Africa, and South America. Through the of computer/telecommunication in regions lacking local infrastructure it is to link individual talent with scientific, engineering, and technical needs worldwide as well as to provide the opportunity for the acquisition of marketable and desired skills and training. In Summer 1999 prototype Viewnet centers will be established in St. Petersburg, Moscow. Yerevan, Kiev, and Dnepropetrovsk which will be linked through evolving lntemet2 systems to participating locations within the United States allowing the rapid transfer of very large files as well as the transmission of the highest quality audio and video. Such multinational connectivity should in the future provide considerable political and economic stability for the world.

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Aviation related, nonliquid petroleum fueled, exothermic reactions

Kauffman C.

Research Bulletin / Warsaw University of Technology, Institute of Aeronautics and Applied Mechanics

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1999

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nr 9

41-45

EN

The usual concept of an aviation fire for vehicles on the ground is that of a large pool fire, or for a in flight, that of an atomized mist finding region sheltered from the high velocity in which to burn. Both situations result the failure of fuel storage and delivery system to the liquid hydrocarbon fuel. However, hydrocarbons are not the only fuel on board the aircraft. There are fuel vapors, passengers and furnishings, equipment, and structure. air may not be the only oxidizer in proximity to these fuels. And. additionally it is to have a wide variety of ignition sources the exothermic chemical reaction. an awareness of the lethality of these has not been seriously addressed by the community, although there have been nunerous previous incidents. The possibility for the occurrence of life threatening exothermic reactions on flight vehicles is illustrated by the presentation of these findings from numerous previous investigations which show how the required components were unexpectedly able to come together and produce damaging consequences. These incidents clearly show that the traditional views of fuel. oxidizer. and ignition source must be considerably broadened and the usual methods of testing, amelioration, confinement, and extinguishment must be examined. Inflight fires and explosions are a very serious cause for concern. And. additionally, it must be recognized that those involved with aviation fire safety must from time to time be concerned with structures which support the operation of aircraft.