Sleep and body rhythm disturbance amongst flight crews in long-range aviation: the problem and potential for relief

Abstract

The research programme to investigate sleep and body rhythm disturbance in long-range aviation was channelled along ‘two paths; the first to investigate the alleged problem and the second to study potential means of relieving any significant problem found to exist. Documentary research revealed no comprehensive work having been published on the subject, although numerous cases involving measurement of performance and body chemistry parameters with disturbed body rhythms were on record. These provided biochemical and some performance support for the hypothesis that a problem existed. In order to obtain further evidence, a participant observation programme extending over several years was carried out, culminating in two surveys of airline cockpit and cabin staff. The one assessed the use of drugs and alcohol to induce sleep and the other assessed the ability of crew members to sleep on board an aircraft, a requirement in certain flight operations. The extent to which this problem could be classified as significant from a health and performance, and thus safety, standpoint, was determined by means of extensive documentary research and personal consultations with specialists in the relevant areas in eight countries in North America and Europe and through correspondence elsewhere. It was concluded that a significant problem existed which was not being seriously addressed within the industry. This led to the second part of the programme involving development of suitable criteria which must be applied to any relief method and a study of methods which might satisfy these criteria. From these methods, three were selected for more profound study, including laboratory work and detailed consideration of adaptation for field application in the flight operational environment. Recommendations were made for further research.