Reported in-flight incapacitation: the early birds of 1911.

Numerous fatal accidents marred the early years of aviation, but not until 1911 was the first accident attributed to inflight incapacitation of the pilot. Two such accidents occurred in 1911 and were reported due to medical causes. Our review of the circumstances surrounding these two accidents lead to different conclusions. We believe them to have been caused by pilot error, and not by medical causes. So the first accident due to inflight incapacitation of the aircrew for medical reasons still remains unknown.

Pilot-induced factors in fatal light aircraft accidents in the United Kingdom: 1969-1981.

The author reviews 52 personally investigated fatal light aircraft accidents involving 8 professional pilots and 44 private pilots. In 22 of the 52 accidents the presence of any pre-crash defect or malfunction of airframe, engine, or flying controls was definitely excluded. In the opinion of the author there was a "pilot-induced" factor in 35 (69.3%) of the 52 fatal accidents. The author discusses the pilot-induced factors associated with some of these accidents and refers to some of the mechanical defects encountered.

Prevalence of fatty liver in healthy male adults accidentally killed.

In a previous publication the author found that the prevalence of fatty liver in healthy aircrew killed in aircraft accidents was 15.6% (1). This paper details the histopathologic features of livers in 166 adult healthy British males between the ages of 18 and 58 yr (mean age 29 yr) accidentally killed. The fatty changes are graded and 35 (21%) are considered to be abnormal. Of the 35 cases, 13 cases show fatty changes unassociated with any other histopathological liver findings and 7 show abnormal liver pathology without fatty changes. Possible aetiological factors are discussed.

Fatal gliding accidents in the United Kingdom: 1960-1980.

For many years, the Department of Aviation and Forensic Pathology of the RAF Institute of Pathology and Tropical Medicine has assisted in the medical investigation of fatal military and civil aircraft accidents, both in the U.K. and overseas. These included 33 glider accidents involving 39 deaths over the period 1960-1980. They do not include all the fatal gliding accidents in the U.K. because there is no mandatory obligation to call in the department, but probably represent over 50%. The Department is primarily interested in the nature of fatal injuries, the performance of safety equipment and the presence or absence of pre-existing medical factors which might have affected or caused the accident. It also makes recommendations intended to improve flight safety, and is often involved in the discussions between the British Gliding Association, the Civil Aviation Authority, and the other organizations involved.

Liver pathology in aircrew.

The aim of this review is to determine the incidence and aetiology of fatty liver and other liver pathology in aircrew. A review of 525 fatal aircraft accidents resulted in deaths of 776 aircrew. Histology of liver, available in 423 aircrew, was reviewed and 118 found abnormal. There were 66 cases (15.6%) of fatty livers. In 11 of the fatty livers and 8 of the 52 non-fatty livers there was histopathologic evidence compatible with alcohol abuse (4.5%). The histopathologic appearances are discussed.

Occurrence of pre-existing disease in aircrew killed in flying accidents.

A review of the occurrence of pre-existing disease found in 809 military, professional, and private aircrew killed in 525 flying accidents in the United Kingdom from 1955 to 1979. In the author's experience, the most common diseases encountered included coronary atherosclerosis, myocarditis, pathology of the liver, psychiatric or adverse medical histories, upper respiratory tract infections, and defective vision. The role of these diseases in accident causation and the need for caution in the interpretation of asymptomatic disease is discussed. The importance of histological examination in death due to trauma and of circumstantial evidence is emphasised.

Prevalence of coronary atherosclerosis in healthy United Kingdom aviators.

The coronary arteries of 288 aircrew (135 military aircrew, 53 professional pilots, and 100 private pilots) killed in 210 aircraft accidents were examined to assess the prevalence of coronary artery disease (CAD). Included in the study were 132 controls of apparently healthy British males aged 18-62 years killed accidentally. The prevalence of significant CAD was found to be 17% in military aircrew with a mean age of 29.1 years, 24.5% in professional pilots with a mean age of 39.7 years and 22% in private pilots with a mean age of 37.2 years. In the control group, the prevalence was 18.2% with a mean age of 29.9 years. There was no evidence of a significant difference in CAD prevalence in the four groups (p greater than 0.1). The difficulties in grading CAD and comparing results with other published series is discussed. When taking the author's military aircrew and professional pilots as one group, so that the prevalence can be compared with previous UK series, it is found that prevalence of significant CAD (19%) is not significantly different from the prevalence reported two decades ago (p greater than 0.1). It is concluded that findings suggest that the prevalence of CAD is not declining in the United Kingdom.

An unsuccessful ejection.

A strike aircraft hit cables and both crew were obliged to eject at low level over the sea. Both canopies deployed fully. The navigator got into his dinghy and was rescued by a helicopter soon afterwards, but the pilot failed to inflate his lifejacket and was dead when the helicopter reached him. The difficulties experienced by the navigator and the probable sequence of events leading to the pilot's death are discussed, and emphasise the need for aircrew to inflate their life preservers before parachuting into water.

Joint Committee on Aviation Pathology: XIV. Ischaemic heart disease: a problem in aircraft accident reconstruction.

A twin-engine light aircraft crashed at night on the third ILS approach. Runway Visual Range was 300 m. All four occupants were killed. The owner, aged 61, one of the two crew members, occupied the left-hand seat and was found to have an old, extensive antero-lateral infarct and severe coronary artery disease. There was no evidence of recent pathological change. A large number of drugs was found in the personal effects of the owner, including Allopurinol, Indomethacin, and Flurazepam. Subsequent investigation revealed that the owner had his PPL withdrawn 12 months prior to the accident on account of myocardial infarction. The problem of pilot control and the significance of cardiovascular disease as a possible cause for the accident are discussed.

Alcohol associated with fatal light aircraft accidents, United Kingdom-1964-1973.

A total of 86 fatal light aircraft accidents in the United Kingdom from January 1964 to December 1973 are reviewed, in which tissue alcohol determinations were undertaken on 102 pilots. Alcohol was detected in 34 cases varying from small amounts of 313 mg/100 ml. The difficulties of interpretation of post mortem tissue alcohol levels are discussed with particular reference to those cases with measured alcohols in excess of 20 mg/100 ml a level taken as possibly significant in context of accident causation. There was 12 pilots, involved in 10 of the 86 fatal accidents, considered as having ingested alcohol before flying, giving an incidence of 11.6% fatal light aircraft accidents with an alcohol involvement. Half of the pilot crashed within 18 min of takeoff, and half had less than 100 h flying experience. It is noted that five of the accidents occurred in 1973. Education of pilots to the hazards of alcohol and flying is the ultimate solution.

Impaired pilot performance: drugs or alcohol.

The circumstances leading to forced landing of a three-seat light cabin monoplane due to engine failure are described. The pilot, an airline pilot employed as a Boeing 707 captain, and one of the two passengers were killed. The liver of the pilot showed diffuse fatty changes and toxicological examination revealed a blood alcohol concentration of 149 mg/100 ml and 139 mg/100 ml in the urine. On initial screening for drugs, the presence of nitrazepam or chlordiazepoxide was suspected and the medical investigation was further complicated by the finding of chlordiazepoxide in the personal effects. Although the cause of the accident was a stall at low altitude during an attempted forced landing following loss of engine power, it was concluded that the pilot's ability to avoid onset of stall was impaired by the concentration of alcohol in his system.