Because fatigue is an undesirable condition scientist and engineers have studied fatigue failure modes in detail. Research has shown that for certain materials we can identify properties and use these material under certain load conditions whereby no failure occurs. This is of course only valid when the material is undamaged. To detect and prevent failure aircraft are inspected at certain intervals to determine the health and status of materials and components. If damage or failure is detected, a detailed inspection of other aircraft might be required. This to ensure the safe operation of all aircraft around the world. This might be one of the outcomes of an accident investigations.