Fatigue Analysis & Fracture Analysis

Colley Aerospace has extensive fatigue analysis and fracture analysis experience with new and aged flight hardware systems. We have the experience to perform fatigue and fracture analyses, using both NASGRO and other classical hand analysis techniques.

Our engineers have performed fracture analyses on countless fracture critical hardware. NASGRO has been the primary tool of choice for these analyses, including the more recent damage tolerance assessments, where it is assumed a much smaller initial crack existed in the structure. The fatigue life was determined using the standard NASGRO/Forman equation methods. Other fatigue assessments were performed using classical hand analysis techniques such as Miner’s Rule and other approaches that take into account the various modification parameters that impact the endurance limit of a component. We have generated fatigue load spectrums using flight data and other industry-standard methods.

Colley Aerospace has generated load spectrums using standard Rainflow algorithms. Our engineers have generated fracture control plans and other requirements documents that pertain to fracture control and life expectancy of aerospace hardware. We have a working knowledge of the test requirements and test methods associated with standard nondestructive evaluation (NDE) techniques, such as eddy current, dye penetrant, magnetic particle, radiographic, and ultrasonic.

The aircraft industry continues to increase its use of composite materials, most noteworthy in the area of primary structural components. The extreme damage tolerance and high strength-to-weight ratio of composites have motivated designers to expand the role of fiberglass and carbon graphite in aircraft structures. This has placed greater emphasis on the development of improved nondestructive inspection (NDI) methods that are more reliable and more sensitive than conventional NDI techniques.

Our knowledge of the sources of damage in composite structures, such as normal and abnormal flight loads, fluid ingress into honeycomb cores, paint strippers and hydraulic fluids, impact damage, heat and UV exposure, et al, provides us with the unique capability of the methods and techniques required to overcome some of the challenges of inspecting damaged hardware. These challenges include hidden damage, small amounts of moisture, heat damage that affects the resin matrix, and weak bonds, either induced due the manufacturing process or during in-service operation.

If you are looking for expertise in one of the areas listed below, please contact us to discuss your project and fracture analysis and fatigue analysis needs.

• NASGRO
• AFGRO
• Classical Analysis Techniques
• Damage Tolerance Analysis and Testing
• Virtual Crack Closure Technique (VCCT)
• Material Fatigue Properties Development
• Fatigue Load Spectrum Development
• Rainflow Counting Algorithms
• Non-Destructive Testing and Evaluation
• Fracture Control Planning and Implementation