characteristic

A characteristic in industrial and regulated manufacturing commonly refers to a defined feature, property, or requirement of a part, assembly, material, or process that must be verified, measured, or controlled. Characteristics are typically documented in engineering drawings, specifications, bills of material, work instructions, or control plans.

Key aspects of a characteristic

In operations and quality contexts, a characteristic usually has:

• A clear definition such as a dimension, tolerance, surface finish, material property, functional requirement, or process parameter.
• An associated specification or limit that states what is acceptable (for example, 10.00 mm ± 0.05 mm, or torque 25–30 Nm).
• An inspection or verification method such as visual inspection, gaging, CMM measurement, functional test, or process monitoring.
• Recorded evidence in inspection reports, electronic forms, MES records, or FAI forms to show whether it conforms.

Characteristics can apply to both products and processes. Product characteristics describe the outcome (for example, hole diameter, flatness, hardness). Process characteristics describe how the outcome is produced (for example, temperature setpoint, machine speed, torque setting on a tool).

Characteristics in FAI and aerospace contexts

In first article inspection (FAI) and standards such as AS9102, a characteristic commonly refers to any requirement on the drawing or specification that must be verified and documented. Each drawing note, dimension, or specification is typically given a balloon or identifier that links it to a corresponding characteristic entry on the FAI report.

Examples include:

• Dimensional characteristics (lengths, diameters, locations, GD&T features).
• Material and special process characteristics (heat treat, coating, NDT results).
• Functional or performance characteristics (pressure test, flow rate, electrical continuity).

Software systems that support FAI or digital inspection often manage characteristics as structured data objects, enabling automated ballooning, characteristic-to-measurement linking, revision control, and traceability across PLM, ERP, and MES.

Operational use of characteristics

Across industrial workflows, characteristics are used to:

• Define what must be inspected or monitored at incoming inspection, in-process checks, and final inspection.
• Drive sampling plans, control plans, and inspection instructions.
• Capture nonconformances when a measured value does not meet the defined characteristic requirement.
• Support statistical analysis such as capability studies, gage R&R, and process control.

Common confusion

• Characteristic vs. requirement: A requirement is the broader obligation (for example, a part must fit and function); characteristics are specific measurable or verifiable elements used to show the requirement is met.
• Characteristic vs. feature (GD&T): In geometric dimensioning and tolerancing, a feature is a physical portion of a part (such as a surface or hole). A characteristic is the parameter applied to that feature (such as its size, position, or orientation) with associated limits.
• Characteristic vs. attribute: In quality statistics, an attribute is a pass/fail or categorical result, while a characteristic can be either variable (measured on a scale) or attribute, depending on how it is defined and recorded.

Tie-back to bottlenecks in FAI workflows

In FAI workflows, each drawing requirement is treated as a characteristic that must be ballooned, transcribed, measured, and documented. Manual handling of hundreds of characteristics can create bottlenecks such as slow ballooning, data transcription errors, fragmented records across PLM/ERP/MES, and limited traceability. Digital systems address these issues by managing characteristics as structured, linked data throughout the inspection and approval process.