Hertel C.E05.0366 Aircraft Extension Drill Bit 27 Hss

Product Description

The HERTEL C.E05.0366 is a wire gauge size 27 aircraft extension drill bit designed for deep-reach drilling applications where standard-length bits cannot access the work zone. Built from high-speed steel with an oxide finish, this bit measures 12 inches in overall length and features a 135-degree split point for self-centering entry without a center punch. The 1.875-inch spiral flute with tapered web configuration and web-thinned geometry reduces thrust and improves chip evacuation. Cutting direction is right hand with two flutes. This bit meets NAS 907 standards and suits general-purpose metalworking in aerospace, aviation maintenance, and fabrication environments.

Aircraft extension drill bits are used when standard-length tooling cannot reach a fastener hole location due to structural depth, obstructions, or access panel constraints. This size 27 bit has a decimal equivalent diameter of 0.1440 inches, making it appropriate for common aircraft-grade fastener pilot holes and clearance holes in sheet metal, aluminum structure, and similar materials. The straight cylindrical shank fits standard drill chucks. Licensed aircraft mechanics, aviation maintenance technicians, and metal fabricators are the primary users of this tool class.

Key Features

• Wire gauge size 27, 0.1440 inches decimal diameter for precision fastener hole sizing
• 12-inch overall length provides extended reach into deep or obstructed work areas
• 135-degree split point is self-centering and reduces walking on entry
• High-speed steel construction with oxide finish for durability in metal drilling
• Web-thinned, tapered web design lowers cutting thrust and improves chip flow
• Meets NAS 907 standard for aircraft extension drill bits

Compatibility

Designed as an OEM-style general-purpose aircraft extension drill bit compatible with standard drill chucks accepting a 0.1440-inch straight cylindrical shank. Conforms to NAS 907 dimensional and performance standards.

Installation Notes

Installation of this drill bit is performed by licensed aircraft maintenance technicians or qualified metal fabricators following applicable maintenance manual procedures and workplace safety protocols. Secure the shank fully in the drill chuck before operation and verify chuck tightness. Always wear appropriate eye protection when drilling metal. Follow applicable Aviation Maintenance Technician Handbook guidance and facility FOD control procedures when working in aircraft structures.