Development of a Multi Spindle Flexible Drilling System for Circumferential Splice Drilling Applications on the 777 Airplane

Flex Track Drilling systems are being used increasingly in aerospace applications providing low cost, highly efficient automated drilling systems. Certain applications like circumferential splice drilling on large size airplane fuselages require multi spindle flex track systems working in tandem to meet production efficiency requirements. This paper discusses the development of a multi spindle flex track drilling system for a circumferential splice drilling on the 777 airplane.

The multi spindle system developed uses a variety of flex track carriages attached to the flexible vacuum tracks to allow for offset or wide inside drilling. Segmented machine programmes allow these multiple machines to be deployed on the same circumferential splice on the airplane providing the multi spindle system. Interfacing of the multiple spindles is achieved by a custom OEM interface using a single screen thereby ensuring simplicity of operation. A central database location ensures that all programmes are current and maintains operational status of all holes being drilled. Tool life monitoring is also provided to ensure consistent tool changeovers for maintaining hole quality and process capability. Flexible track lengths can be spliced together for long lengths and shortened for clearance or areas using smaller programmes. This paper also discusses the development of the carriage hardware specific to the 777 airplane requirements using the methodology of adapting existing flex track system designs as well as point design specific to the 777 Fuselage Circumferential Splice Drilling Application.