Aerospace fiber optic cables frequently need to be spliced, both for original installation and for repair. Key requirements include low insertion loss, high return loss, ease of installation under difficult situations, and mechanical and environmental stability, suitable for the adverse conditions in aircraft. Expedient mechanical splicing can offer advantages of rugged and relatively inexpensive installation equipment, and the finished cable restorations may not be required to be permanent. An important goal of expedient splicing is to restore satisfactory system operation, as quickly as possible, to complete a mission and return an aircraft safely to a secure location. Mechanical fiber optic cable splices have long existed in the telecommunications industry, but they were never designed, nor are they generally suitable, for challenging aerospace applications. The industry needs agreed-upon performance standards for mechanical fiber optic cable splices suitable for aerospace service.