A technique using a simple optical arrangement (called D-Sight) involving a source of light and a retroreflective screen was patented by Diffracto Ltd. The method was used to locate indentations associated with low energy impact damage. In graphite/epoxy specimens good correlation was observed between internal impact damage as shown on ultrasonic C-scan images and indentations detected with the D-Sight method. Test specimens are currently mounted on an aircraft to observe the influence of in-service surface degradation on technique resolution. The method has the potential for inexpensive, rapid and objective detection of low energy impact damage over large areas of composite aircraft structure. Application of this method, because of its inherent reliability, could result in the increasing of the design allowable strain levels for some composite components.