The size and consequences of low back pain (LBP) in Norwegian helicopter aircrew has been investigated in a retrospective and prospective survey. With 50.5% reporting such pain in a 2-yr period, and Sea King aircrew reporting LBP on on almost half (49.3%) of the missions flown, the magnitude of the problem equals that reported from other air forces. Pilots reported LBP six times more often than other crewmembers and almost half (48.6%) felt the pain influenced the quality of work. This could have flight safety implications. Crewmembers with total flying time over 2,000 h have a significantly higher incidence of sick leave than those with less than 2,000 h. Only 1 pilot out of 10 with total flying time under 500 h had had flight-related LBP.