General Aviation Accidents Research Articles

Alcohol and aviation

Aviation accidents due to alcohol consumption by aircrew appear to be rare, especially in commercial aviation. However, a small proportion of general aviation accidents are attributable to alcohol use by aircrew, and aircrew are not well informed about the metabolism of alcohol and its effects on performance. Furthermore, there is evidence that aircrew performance may be impaired by alcohol consumption even after their Blood Alcohol Concentration has returned to "zero" (i.e. < 5 mg/dl). Accidents caused by impairment of aircrew performance by alcohol may therefore not be attributed to alcohol use at all. Aviation safety relies upon faultless human performance and is thus highly sensitive to alcohol-related impairment of performance. This paper provides a review of research regarding aircrew alcohol consumption, impairment of aircrew performance by alcohol, incidence of aviation accidents attributable to alcohol use by aircrew, and other related subjects.

Age-Related Changes in Selected Status Variables in General Aviation Pilots

Nine status variables were analyzed in an attempt to narrow the focus of where, within the active pilot population, to look for some of the factors that may be associated with increase in risk of becoming involved in a general aviation accident. Epidemiological analysis of general aviation pilots indicates that there is a significant rise in the accident rate for pilots after age 39. An analysis was made of changes in the frequency of occurrence of selected status variables between pilots in the 35 to 39 and those in the 40 to 44 age groups who were involved in general aviation accidents in 1992, 1993, and 1994; between pilots in the 35 to 39 and those in the 40 to 44 age groups in the active pilot population; and between accident-involved pilots and those in the active pilot population. Status variables analyzed were Federal Aviation Administration pilot and medical certificates, instrument rating, flight time, pilot occupation and gender, and purpose of the accident flight. The two age groups of accident-involved pilots differed on only one variable. However, examination of the data showed two distinct differences between accident-involved pilots and the active pilot population. The most substantial finding for both age groups was that accident-involved pilots were significantly different from the active pilot population. Second, with the exception of class of FAA medical certificates, accident-involved pilots did not differ significantly with age whereas the active pilot population differed significantly over five status variables.

Age-Related Changes in Selected Status Variables in General Aviation Pilots

Nine status variables were analyzed in an attempt to narrow the focus of where, within the active pilot population, to look for some of the factors that may be associated with increase in risk of becoming involved in a general aviation accident. Epidemiological analysis of general aviation pilots indicates that there is a significant rise in the accident rate for pilots after age 39. An analysis was made of changes in the frequency of occurrence of selected status variables between pilots in the 35 to 39 and those in the 40 to 44 age groups who were involved in general aviation accidents in 1992, 1993, and 1994; between pilots in the 35 to 39 and those in the 40 to 44 age groups in the active pilot population; and between accident-involved pilots and those in the active pilot population. Status variables analyzed were Federal Aviation Administration pilot and medical certificates, instrument rating, flight time, pilot occupation and gender, and purpose of the accident flight. The two age groups of accident-involved pilots differed on only one variable. However, examination of the data showed two distinct differences between accident-involved pilots and the active pilot population. The most substantial finding for both age groups was that accident-involved pilots were significantly different from the active pilot population. Second, with the exception of class of FAA medical certificates, accident-involved pilots did not differ significantly with age whereas the active pilot population differed significantly over five status variables.

General Aviation Airplane Accidents Involving Spatial Disorientation

National Transportation Safety Board accident data for 1983-1991 were used to compare those general aviation accident cases that involved spatial disorientation (SD) with all others. About 2.1% of general aviation airplane accidents involved SD. Those accidents were associated with low ceilings, restricted visibility, precipitation, darkness and instrument flight conditions. Pilots in certain professions, particularly those in business, were more involved in SD accidents. Pilots in SD accidents were more often under pressure, fatigue, anxiety, physical impairment and alcohol or drugs. The pilots' total and night flying experience were inversely related to involvement in SD accidents. Spatial disorientation accidents accounted for a small number of crashes, but they were very severe-fatalities occurred in 92%, they accounted for 9.9% of the fatal accidents, 11% of the fatalities and in 95% the aircraft were destroyed. The results suggest that the pilots in SD accidents lacked the flight experience necessary to recognize or cope with the stimuli that induce SD, which was compounded by fatigue, alcohol/drugs or pressure and other psychological and physical impairments. Specific exposure to conditions leading to SD in training of general aviation and all pilots should be evaluated to help them to recognize it, and the techniques used by experienced pilots to combat its onset and effects should be studied and used in training. Improved human factors engineering of the cockpit instrumentation is also needed.

Pilot Disorientation as the Most Frequent Cause of Fatal, Weather-Related Accidents in UK Civil and General Aviation

Over 20 years ago, collision with high ground was identified as being the single most significant cause of fatalities among air travellers worldwide (Smith, 1968), and some human factors responsible were highlighted. The three factors most commonly found to be present during major civil aviation accidents were: (i) pilot's visual flight in instrument meterological conditions (IMC); (ii) navigational error by the crew and'; (iii) pilot's failure to react correctly to new circumstances resulting from air traffic control (ATC) instructions or advice – sometimes made in a language foreign to that of the aircrew. The latter factor will be tested here to see if it still applies to recent cases in the UK.

An Analytical Study of the Effects of Age and Experience on Flight Safety

The purpose of this study was to determine whether there are any significant decreases in the safety and effectiveness of pilots by age 60. The data for this study comes from records of general aviation accidents (i.e., for private pilots, commercial pilots, and air transport pilots). This accident data has been acquired from many specialized aviation data banks, these include: NTSB, AOPA, FAA, and the COMSIS Research Corporation. The data were organized into groups according to age of the pilot-in-command (PIC) responsible for the accident. The grouping progresses in five-year increments starting at 20–24, and ending with 55–59. The data were analyzed in terms of different accident statistics (i.e., based upon the number of pilots and the number of hours flown). The results indicate that age and experience both affect safety. The magnitude of these effects and their implications for aviation safety are discussed.

Toxicological Findings in Federal Aviation Administration General Aviation Accidents

Blood, urine, and tissue specimens were received from 377 Federal Aviation Administration (FAA) aviation fatalities during fiscal year 1989. Carbon monoxide at less than 10% saturation was found in 94% of the cases, and cyanide at less than 0.5 mg/L was found in 96% of the cases. Ethanol at greater than 10 mg/dL was found in 14.8% of the cases, but only 4.5% were determined to be due to ethanol ingestion from toxicological findings. Excluding nicotine and ethanol, 12.6% of the cases were positive for one or more drugs. Acetaminophen and salicylate were the most frequently found drugs. Cannabinoids were found in 1.3% of the cases and benzoylecgonine in 1.6%. There was minimal use of therapeutic drugs that cause central nervous system depression or stimulation. These results show no consistent pattern of drug involvement in civilian aviation fatalities.

Analysis of General Aviation Accidents during Operations under Instrument Flight Rules

The purpose of this analysis was to describe some of the errors that pilots make during flight under instrument flight rules (IFR). The data suggest that there is less risk during the approach and landing phase of IFR flights, as compared to operations under visual flight rules. During the 1980s, there was a large increase in the number of single-pilot IFR (SPIFR) accidents. Most of these were the result of an increase in air taxi accidents. But, because of the increase in air taxi operations, there was no change in the SPIFR rate. SPIFR accident rates continue to be higher than dual-pilot IFR, reflecting the high work load of IFR operations. Night SPIFR continues to be dangerous; its rate is almost 10 times the rate of day IFR, and twice that of day non-IFR operations. The relatively static nature of the statistics for IFR accident rates may be accounted for by (1) the fact that there has been little change in general aviation cockpit technology during the last 25 years, (2) training techniques have not had an impact on pilot operations, and/or (3) current display technology promotes certain types of pilot errors that are virtually immune to training.

Air transport pilot involvement in general aviation accidents : S. Salvatore, M. D. Stearns, and M.S. Huntley, Ergonomics, November 1986, 29(11), 1455–1467

Relationships between several family, behavioral, and developmental factors and injuries in mid-childhood were investigated. The sample consisted of 781 children from a longitudinal study of health and development in Dunedin, New Zealand. Self-reported injury data were obtained when the children were 9 and 11 years of age, and a wide range of family, behavioral, and developmental factors were measured when the children were 7, 9, and 11 years of age. The principal form of statistical analysis was multivariate analysis of variance with a repeated measures design. The results showed that none of the family, behavioral, and developmental variables had a significant association with injury scores. Sex was the only significant factor in predicting injury experience, with males having significantly higher injury rates than females. The findings were compared with other studies. In addition, the practical implications of this type of research and future directions of childhood injury research were discussed.

Air transport pilot involvement in general aviation accidents.

Abstract General aviation (GA) fatal accident records of airport transport pilots (ATPs) were compared to those of private pilots (PVTs). ATPs are safer GA pilots than the PVTs. They have comparable exposure in GA airplanes and account for 7·5% of all certified to fly, but only 3·5% of the fatal accidents. ATPs are less often involved in pilot-induced accidents. Nearly 50% of ATP pilot-induced accidents occur during aerobatics. Often these risky aerial operations are performed below a safe altitude and are associated with the descriptors ‘careless’ and ‘reckless’. The ATP aerobatics-related fatality is likely to occur in a multi-wing aeroplane with which he has little experience. The ATP aerobatics-related accident is likely to be of the spin, stall, or controlled flight into terrain variety, and to occur in summer or early autumn.

Fail and Be Safe

An American study of 22,002 general aviation accidents revealed that 59 per cent of the incidents where fires broke out resulted in fatalities.

Federal board seeks to reduce toll from general aviation accidents

The standards for occupant protection in general aviation [noncommercial] aircraft have remained essentially unchanged for about the last 30 years, says the National Transportation Safety Board. So the five-member Washington, DC, board is in the midst of a multiyear project to deal with the problem. What concerns the board, as well as many physicians, is that more than 21,000 persons were killed or seriously injured in 41,319 general aviation accidents over a ten-year period beginning in 1972. About one third of these accidents were not classified as severe, such as hard or gear-up landings or nosing-over after landing, and the board says most of the deaths and serious injuries in those nonsevere accidents could have been avoided. Reporting on the first phase of its study project, the board says some preliminary findings indicate that problems may exist concerning the adequacy of seat and restraint [lap and shoulder belts] certification and

Federal board seeks to reduce toll from general aviation accidents

Federal board seeks to reduce toll from general aviation accidents

National Risk Assessment for Carbon Fibers Released from Aircraft Fires

Carbon fibers released from accidental aircraft fires may present a hazard in electronic equipment within u large radius. Two separate methodologies to quantify the associated economic risks were developed and applied, each providing a useful general approach to probabilistic risk assessment. For the case of commercial air carrier accidents, which are infrequent but may release large amounts of carbon fiber. A Monte Carlo simulation was performed for 26 major airports and then the results were aggregated into a national risk profile. For the case of general aviation accidents, which are frequent but release only small amounts, an analytic approach based on the Poisson process was used to estimate the risk profile. The results indicated that the potential economic losses due to carbon fiber usage in civilian aircraft were relatively low.

General Aviation Accidents: Postcrash Fires and How to Prevent or Control Them

General Aviation Accidents: Postcrash Fires and How to Prevent or Control Them

Some Lessons learned from Aircraft Accidents—The Engineering Aspects

A survey of both public transport and general aviation accidents which occurred in the United Kingdom over the past 20 years will show that material failure in various forms has accounted for, or contributed to, approximately 25 per cent of the major accidents. The effects of these failures often become closely interwoven with human reaction during stressful situations and the subsequent operation of the aircraft, but a smaller proportion of catastrophic failures were primary causes of accidents in their own right. The failures in these cases were mainly due to errors of omission or lack of foresight in the design and manufacture stages, the results of which could not have been influenced nor ameliorated by the efforts of the operating crew or the vigilance of those responsible for day to day line maintenance.

Correlation of General Aviation Accidents with the Biorhythm Theory

Biorhythms were calculated for over 4,000 pilots involved in general aviation accidents in 1972. Data were obtained from the files of the National Transportation Safety Board. Exact date and time of accident were used, and 1200 hours (noon) was used as the average time of birth. Data were analyzed for correlation of aircraft-accident occurrence with both biorhythmically critical days and with individual and multiple low or negative phases of cycle. Data were calculated by both a 24- and 48-hour critical period and by all three cycles (physical, emotional, and intellectual) or only the physical and emotional cycles. Data did not deviate significantly from the random model, when analyzed by chi-square at the p = 0.1 level. No correlation was found between accident occurrence and biorhythmic criticality or low phase of cycle. This was true both for the cases in which the primary cause of the accident was attributed to pilot involvement and for those in which it was not.

Conquest over ice

Obesity, affects a third of the US population and its corollary occupant weight adversely impacts safe flight operations. Increased aircraft weight results in longer takeoff/landing distances, degraded climb gradients and airframe failure may occur in turbulence. In this study, the rate, temporal changes, and lethality of accidents in piston-powered, general aviation aircraft related to exceeding the maximum aircraft weight/center of gravity (CG) limits were determined.Nation-wide person body mass were from the National Health and Nutrition Examination Survey. The NTSB database was used to identify accidents related to operation of aircraft outside of their weight/CG envelope. Statistical analyses employed T-tests, proportion tests and a Poisson distribution.While the average body mass climbed steadily (p < 0.001) between 1999 and 2014 the rate of accidents related to exceedance of the weight/CG limits did not change (p = 0.072). However, 57% were fatal, higher (p < 0.001) than the 21% for mishaps attributed to other causes/factors. The majority (77%) of accidents were due to an overloaded aircraft operating within its CG limits. As to the phase of flight, accidents during takeoff and those occurring enroute carried the lowest (50%) and highest (85%) proportion of fatal accidents respectively.While the rate of general aviation accidents related to operating an aircraft outside of its weight/CG envelope has not increased over the past 15 years, these types of accidents carry a high risk of fatality. Airmen should be educated as to such risks and to dispel the notion held by some that flights may be safely conducted with an overloaded aircraft within its CG limits.