The EN 4641 standard series describes various optical cables (fibre optic cables) with a fibre cladding outside diameter of 125 µm for aerospace applications. Part 103 specifies the general characteristics, conditions for qualification, acceptance and quality assurance for a fibre optic cable with a 62,5/125 µm single mode fibre core, 2,74 mm outside cable diameter, ruggedized simplex construction and of semi-loose construction. The basic construction is the cable defined in EN 4641-102 with added sheaths for ruggedized usages. The standards of the EN 4641 series have been prepared by ASD-STAN, Technical Section Electrics, Avionics, with the participation of German experts of the Aerospace Standards Committee. The European Committee for Standardization (CEN) declared the Aerospace and Defence Industries Association of Europe (ASD-STAN) responsible for the preparation of European standards (EN) for the field of aerospace. The responsible German standardization committee is Working Committee NA 131-04-10 AA "LWL und LWL-Komponenten" ("LWL and LWL-components") of the Aerospace Standards Committee at DIN.