Overview
ISO 14279:2002 - "Aerospace - Drives, internal, cruciform - Metric series" specifies the dimensions of internal cruciform (cross-shaped) drives used in metric screws for aerospace applications. The standard covers the nominal thread diameter range 1.6 mm to 20 mm, defines drive geometry for different head types, and presents dimensions and tolerances in millimetres. Figures (1–4) and Tables (1–4) give the detailed configurations and numeric data for drive codes (R0–R5).
Key topics and requirements
- Drive geometry and dimensions: Detailed profiles for internal cruciform drives (metric series) referenced by drive codes; dimensions are given in tables for precise manufacturing and inspection.
- Head configurations covered: Normal 100° countersunk head, reduced 100° countersunk head, and pan head - each with specific drive dimension tables.
- Dimensional units and tolerancing: All dimensions and tolerances are expressed in millimetres; location tolerances presentation conforms to ISO 1101.
- Scope limits: Applies specifically to metric internal cruciform drives used with screws having nominal thread diameters from 1.6 mm to 20 mm.
- Associated tooling: Drivers and gauges used with these drives are defined in ISO 14280 and ISO 14281 respectively.
- Normative references: The standard cites related aerospace fastener standards (e.g., ISO 3202, ISO 5856, ISO 13921, ISO 7913) that govern screw/head forms and tolerances.
Applications
ISO 14279 is used to ensure interchangeability, fit, and functional compatibility of cruciform internal drives in aerospace fasteners. Practical uses include:
- Designing screw heads and mating drivers for aircraft structures and components.
- Specifying fastener geometry in procurement and drawings to ensure supplier conformity.
- Setting inspection criteria and acceptance gauges for quality control and assembly verification.
- Reducing assembly failures related to driver engagement, torque transfer, and wear in safety-critical aerospace assemblies.
Who uses this standard
- Aerospace fastener designers and mechanical engineers
- Manufacturing and assembly engineers
- Quality assurance and inspection teams (use gauges per ISO 14281)
- Tooling and driver manufacturers (see ISO 14280)
- Procurement and compliance officers specifying fastener requirements
Related standards
Keywords: ISO 14279:2002, internal cruciform drives, metric series, aerospace fastener standards, drive dimensions, metric screws, countersunk head, pan head, drivers and gauges.