Introduction Since the 1914–1918 war, when high psychiatric casualty rates were recorded amongst military aircrews, a considerable amount of research has been focussed on the psychiatric problems associated with aviation. Reported symptoms have included morbid anxiety, lethargy; anorexia, weight loss; restlessness, tremors, palpitations; depression, insomnia, nightmares; personality changes, loss of flying skills and avoidance of risks. Diverse opinions have been expressed on the genesis and therapeutic management of the syndromes. Some authors have drawn attention to the so-called neurasthenic features and concluded that the symptoms were predominantly physiogenic, reflecting a state of exhaustion arising from neural, biochemical or other mechanisms (e.g. Ferry, 1919; Josué, 1919; Head, 1919; Flack, 1920; Porton, 1936; Miller, 1936; Lottig, 1937; Walshe, 1941; Cobb, 1942). Some have distinguished between ‘neurasthenic’ symptoms and overt anxiety, ascribing the former to physical exhaustion and the latter to neurotic disturbance in predisposed individuals (e.g. Gotch, 1919; Armstrong, 1936; Hastings et al. 1944; Murray, 1944).