Damage Diagnosis and Prognosis Methodology to Estimate Safe Load for Aircraft Structure

The next generation of resilient aircraft control systems needs to have the ability to adaptively respond to off-nominal flight conditions, including the incurrence of structural discrete-source damage during flight. Hence, development of efficient methodologies to determine the presence, location, and severity of damage in critical structural components is important in developing efficient structural health management systems. To avoid loss of control due to off-nominal conditions during a flight, load levels must be controlled such that it is safe to continue the flight without failure. Hence, a capability is needed for accurate real-time predictions of residual strength in aircraft structures with complex damage configurations. Elastic-plastic fracture-mechanics-based failure assessment diagrams combined with crack-tip opening displacement assist in determining whether the structure is safe under current operational loading conditions. A range of materials and thicknesses used in the aerospace industry...