Urinary calculosis is, according to the different medical statistics, one of the most common diseases among flight personnel. The causes which favour urolithiasis are reviewed in relation with the flight factors themselves and the type of life which these professionals lead. Diet, low intake of fluids, and the loss of water through the skin and lungs, are together with the sedentary nature of the work the most obvious causes as etiological factors. The risks which this pathology supposes for flight personnel and their suitability for flight under these conditions are studied. Likewise, the measures which should be established to prevent this anomaly as far as possible are reviewed.