AS9103: An introduction to variation management of key characteristics in aerospace and defense manufacturing
Defined by IAQG, AS9103 is a standard for variation management of key characteristics. It aims to ensure consistency and accuracy in the manufacturing of parts in the aerospace and defense industry, while driving process innovations through effective planning and management of key characteristics variation.
Although the standard is primarily intended to apply to new parts, it’s also applicable throughout the lifecycle of a product to ensure changes are taken into account. It’s relevant for all production processes that impact the variation of key features, and throughout aerospace and defense supply chains – including basic materials and organizations that produce product design characteristics.
The AS9103 standard outlines a range of requirements and provides a process for managing key characteristics variation.
What is a key characteristic?
A key characteristic (KC) is defined as any feature of a material, process or part whose variation has a significant influence on fit, service life, manufacturability or performance for its intended use.
Such items are produced at specific dimensional or performance conditions to ensure consistency and quality. Some types of KC might include:
- Dimensional features
- Chemical concentrations
- Time
- Pressure
- Speed
- Rates
- Temperature
Any given feature should only be defined as a KC after a significant benefit of controlling the characteristic has been established. Once this has been determined, variation management should be applied to ensure adherence to specified dimensions.
What is required?
Where required by a purchase order or contract, KCs should be monitored and controlled through variation management until all processes influencing the characteristic are in control, and process capability is established.
A monitoring methodology should be established to ensure continued performance, in addition to the development of a Process Control Document (PCD) that describes the manufacturing plan to control variation in KCs.
There are two requirements options for establishing the proper level of supplier control:
- Outcome-based requirements: these processes are designed to achieve an objective within certain constraints, offering process flexibility in meeting those objectives.
- Activity-based requirements: these processes are more specified to achieve an objective with limited process flexibility.
IAQG lays out a range of core requirements for variation management:
- Perform variation management on KCs
- Identify lower level KCs where necessary
- Create and maintain appropriate documentation
- Establish process capability when KCs are in-control
- Requirements for combined KCs – process control
- Requirements for reduced inspection
- Flow down to subcontractor as appropriate
- Exceptions documented and agreed to by customer
Process for Variation Management
AS9103 describes a 7-step process that can be used to fulfill the standard’s requirements for variation management:
Stage one: Review KCs and required performance
Stage two: Plan a manufacturing process
Stage three: Operate the process on a trial basis to generate data
Stage four: Analyze data for action
Stage five: Take action from study of KC performance
Stage six: Continue to monitor the process
Stage seven: Process change management
Identifying a product’s KCs and ensuring consistent adherence to designs through variation management is crucial to maintaining high quality production. Should your product’s characteristics stray too far from the original specifications, you could face increased wastage, reduced customer satisfaction, and non-compliance. In the aerospace and defense industry, non-compliance can have serious consequences – such as increased risk to personal safety or mission success.
AS9103 outlines the requirements and process recommendations for effective KC variation management. By complying with this standard, manufacturers can ensure consistent quality that meets customer requirements.