| The aircraft industry is using a significant amount of composite materials in modern aircraft due in part to their high strength to weight ratio. Sandwich composites, two thin sheets surrounding a foam or honeycomb core, are known to be prone to impact damage due to the thin top sheet. Relatively small impacts can create indentations in the surface and in some cases disbonding of the top sheet from the honeycomb. This type of disbond defect can greatly decrease the strength of a sandwich composite. This report will analyse the response to impact damage of a composite honeycomb floor panel from the Cormorant helicopter.; First, a Cormorant floor panel was segmented, with each segment subjected to differing impact energies. Following the damage to the floor panel segments, each was tested using traditional ultrasound, pulse-echo, through transmission and guided waves to quantify the damage. Pulse-echo ultrasound was used to quantify surface indentation. Through transmission ultrasound and guided waves were able to identify and characterize disbonds.; Based on these results, a correlation was found between the surface indentation diameter and the disbond diameter. From this correlation, two visual inspection techniques, Double Pass Retro-reflection of Light (D Sight) and Edge of Light, were performed on the test pieces to investigate their ability to identify and size the surface indentations caused by impact and to correlate these indentation measurements to a respective disbond size.; D Sight was found to be capable of providing a fast, reliable, cost effective, portable nondestructive evaluation (NDE) method for measuring disbonds in the Cormorant floor panel. |
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