Luminescent Coating for Indicating Composite Impact Damage

This proposal describes work in developing a luminescent coating for the passive monitoring of impact sites on composite airframe structures. Despite high strength to weight ratios, graphite fiber composite materials are susceptible to significant internal damage due to impact from runway debris, human carelessness, and bird strikes. Identification of these impact sites is vital to aircraft performance and lifetime. During Phase I, we will demonstrate a luminescent coating that will indicate impacted sites as well as the magnitude of the impact sustained. The result of impact is a change in the coating's emission properties, which can be detected through an imaging or spectroscopic system. Maintenance and inspection ground crew would easily be able to carry out this task. Phase II research will involve the development of a prototype system comprised of the coating, detection hardware, and processing software.