Upon Closer Inspection...U.S. Naval Aviation Mishaps 1977-1992

The U.S. Navy/Marine Corps Class A flight/flight-related mishap rate has declined markedly since 1953. However, analysis of all Class A, B, and C naval aviation mishaps between January 1977 and December 1992 reveals that mishaps attributable to human factors have declined at a slower rate than those attributable to mechanical/environmental factors. Upon closer inspection of the data, marked differences were evident between single-piloted and dual-piloted aircraft. Global trends were primarily a function of single-piloted aircraft, particularly when phase of flight and time of day that a mishap occurred are considered. Previously reported improvement in aviation safety may be biased by global assessments that do not differentiate among mishap causal factors and single- versus dual-piloted aircraft

A Human Error Analysis of Commercial Aviation Accidents Using the Human Factors Analysis and Classification System (HFACS)

The Human Factors Analysis and Classification System (HFACS) is a general human error framework originally developed and tested within the U.S. military as a tool for investigating and analyzing the human causes of aviation accidents. Based upon Reason’s (1990) model of latent and active failures, HFACS addresses human error at all levels of the system, including the condition of aircrew and organizational factors. The purpose of the present study was to assess the utility of the HFACS framework as an error analysis and classification tool outside the military. Specifically, HFACS was applied to commercial aviation accident records maintained by the National Transportation Safety Board (NTSB). Using accidents that occurred between January 1990 and December 1996, it was demonstrated that HFACS reliably accommodated all human causal factors associated with the commercial accidents examined. In addition, the classification of data using HFACS highlighted several critical safety issues in need of intervention research. These results demonstrate that the HFACS framework can be a viable tool for use within the civil aviation arena

A Human Error Analysis of General Aviation Controlled Flight Into the Terrain Accidents Occurring Between 1990-1998

Although all aviation accidents are of interest to the Federal Aviation Administration (FAA), perhaps none is more disconcerting than those in which a fully functioning aircraft is inexplicably flown into the ground. Referred to as controlled flight into terrain (CFIT), these accidents continue to be a major safety concern within aviation, in particular general aviation (GA). A previous study as part of the FAA\u27s Safer Skies agenda examined 165 CFIT accidents using root cause analysis and developed 55 interventions to address their causes. While the study represented the work and opinions of several experts in the FAA and industry, the findings might have benefited from a more detailed human error analysis involving a larger number of accidents. In this study, five pilot-raters independently analyzed more than 16,500 GA accidents occurring between 1990-1998 using the Human Factors Analysis and Classification System (HFACS). Of the GA accidents examined, 1407 were identified as CFIT and compared with non-CFIT accidents using HFACS. The analysis revealed a number of differences in the pattern of human error associated with CFIT accidents. Findings from this study support many of the interventions identified by the CFIT Joint Safety Analysis Team (JSAT) and Joint Safety Implementation Team (JSIT), permitting safety professionals to better develop, refine, and track the effectiveness of selected intervention strategies

The Human Factors Analysis and Classification System--HFACS

Human error has been implicated in 70 to 80% of all civil and military aviation accidents. Yet, most accident reporting systems are not designed around any theoretical framework of human error. As a result, most accident databases are not conducive to a traditional human error analysis, making the identification of intervention strategies onerous. What is required is a general human error framework around which new investigative methods can be designed and existing accident databases restructured. Indeed, a comprehensive human factors analysis and classification system (HFACS) has recently been developed to meet those needs. Specifically, the HFACS framework has been used within the military, commercial, and general aviation sectors to systematically examine underlying human causal factors and to improve aviation accident investigations. This paper describes the development and theoretical underpinnings of HFACS in the hope that it will help safety professionals reduce the aviation accident rate through systematic, data-driven investment strategies and objective evaluation of intervention programs

Human Error and Accident Causation Theories, Frameworks and Analytical Techniques: An Annotated Bibliography

Over the last several decades, humans have played a progressively more important causal role in aviation accidents as aircraft have become more [complex]. Consequently, a growing number of aviation organizations are tasking their safety personnel with developing safety programs to address the highly complex and often nebulous issue of human error. However, there is generally no “off-the-shelf” or standard approach for addressing human error in aviation. Indeed, recent years have seen a proliferation of human error frameworks and accident investigation schemes to the point where there now appears to be as many human error models as there are people interested in the topic. The purpose of the present document is to summarize research and technical articles that either directly present a specific human error or accident analysis system, or use error frameworks in analyzing human performance data within a specific context or task. The hope is that this review of the literature will provide practitioners with a starting point for identifying error analysis and accident investigation schemes that will best suit their individual or organizational needs

Tyrosine as a Countermeasure to Performance Decrement During Sleep Loss

The fatigue and cognitive performance deficits associated with sleep loss and stress have motivated the search for effective nonpharmacological countermeasures. The purpose of the present study was to examine the potential behavioral effects of tyrosine, an amino-acid presursor to dopamine and norepinephrine, during an episode of continuous nighttime work involving one night of sleep loss

Fermions in the harmonic potential and string theory

We explicitly derive collective field theory description for the system of fermions in the harmonic potential. This field theory appears to be a coupled system of free scalar and (modified) Liouville field. This theory should be considered as an exact bosonization of the system of non-relativistic fermions in the harmonic potential. Being surprisingly similar to the world-sheet formulation of c=1 string theory, this theory has quite different physical features and it is conjectured to give space-time description of the string theory, dual to the fermions in the harmonic potential. A vertex operator in this theory is shown to be a field theoretical representation of the local fermion operator, thus describing a D0 brane in the string language. Possible generalization of this result and its derivation for the case of c=1 string theory (fermions in the inverse harmonic potential) is discussed.Comment: 29 pages, 4 figures, LaTeX2e. v2 - minor correction

Complex Curve of the Two Matrix Model and its Tau-function

We study the hermitean and normal two matrix models in planar approximation for an arbitrary number of eigenvalue supports. Its planar graph interpretation is given. The study reveals a general structure of the underlying analytic complex curve, different from the hyperelliptic curve of the one matrix model. The matrix model quantities are expressed through the periods of meromorphic generating differential on this curve and the partition function of the multiple support solution, as a function of filling numbers and coefficients of the matrix potential, is shown to be the quasiclassical tau-function. The relation to softly broken N=1 supersymmetric Yang-Mills theories is discussed. A general class of solvable multimatrix models with tree-like interactions is considered.Comment: 36 pages, 10 figures, TeX; final version appeared in special issue of J.Phys. A on Random Matrix Theor

Integrable Structure of Interface Dynamics

We establish the equivalence of a 2D contour dynamics to the dispersionless limit of the integrable Toda hierarchy constrained by a string equation. Remarkably, the same hierarchy underlies 2D quantum gravity.Comment: 5 pages, no figures, submitted to Phys. Rev. Lett, typos correcte

k-string tensions in SU(N) gauge theories

In the context of four-dimensional SU(N) gauge theories, we study the spectrum of the confining strings. We compute, for the SU(6) gauge theory formulated on a lattice, the three independent string tensions sigma_k related to sources with Z_N charge k=1,2,3, using Monte Carlo simulations. Our results, whose uncertainty is approximately 2% for k=2 and 4% for k=3, are consistent with the sine formula sigma_k/sigma = sin(k pi/N) / \sin(pi/N) for the ratio between sigma_k and the standard string tension sigma, and show deviations from the Casimir scaling. The sine formula is known to emerge in supersymmetric SU(N) gauge theories and in M-theory. We comment on an analogous behavior exhibited by two-dimensional SU(N)xSU(N) chiral models.Comment: version accepted for publication in Phys Rev D (Rap Comm