A system of thin, light-conducting fibres, integrated into a composite structure during its manufacturing process, can serve as a reliable, automatic and remote working long-term monitoring device for structural damage. Fractures, cracks or delaminations in a structure area can destroy the optical fibres installed there and thus interrupt the light flow. Various examples of applications in gfrp aircraft components are described. The outline of a complete fibre optic nervous system ( fons) for large Airbus cfrp components shows how fibre optic damage detection can contribute to future aircraft maintenance and inspection philosophies. Following the example of other aircraft systems including engines and computers, the structure can also be included in the permanent and automatic working central fault detection system ( cfds).