Spontaneous pneumothorax (SP) is infrequently diagnosed in aircrew personnel. However, once it is diagnosed, aircrew disposition becomes a serious concern. To evaluate this problem, a literature review was conducted to put the disease into proper perspective. A questionnaire was then sent to all aircrew in the United States Air Force waiver file who had suffered SP in order to gain a retrospective view of problems and situations encountered. The following areas were investigated: recurrences, height, weight, age, smoking history, initial medical management, symptomatology, activity at time of occurrence, relationship to flight duties, treatment given and personal/family history of lung disease. A review of FAA, military, and NASA guidelines regarding personnel with a history of SP was also done. It is concluded that SP is an unrecognized hazard to aircrew personnel. Once an SP has been diagnosed in an individual, he/she should be grounded from further flight duties until either 9 years have elapsed without a recurrence or there has been a bilateral parietal pleurectomy.