Earlier this year the Automotive Industry Action Group (AIAG) released updated copies of their APQP and Control Plan reference guides (available at www.aiag.org). This release is significant in that it includes the introduction of the stand-alone control plan document to provide guidance for completing control plans.
Control plans are used to identify the important product and process characteristics for manufacturing quality products in a manufacturing process. The objective of the control plan is straightforward: it outlines the plan to control the process. Although control plans are meant to identify important product and process characteristics, some control plans tend to sway toward product over process (this has been a historic bias, although most control plan training stresses a product and process approach). Control plans are applicable to any measurable and controllable process – not just manufacturing. Many organizations should take note of these documents as many a customer has arrived at their supplier’s location to review a non-conformance, process change, or new product approval and requested to review the control plan and walk the process.
AIAG’s creation of a stand-alone control plan document is critical to support advancements in product and process technology and a significant step in standardizing the guidance for completing control plans. The APQP Second Edition book, where control plan was formerly housed, included examples of control plans and some guidance as to what content goes where on the form, but it didn’t provide a methodology for how to prepare and complete the document. As control plans are consistently in the top ten of IATF major and minor non-conformances, this new approach provides a documented methodology to help organizations develop more robust and useable control plans. This document is a good first step in reducing customer specific requirements (CSRs) for control plans plus provides the added benefit of including several callouts identifying when it is appropriate to seek guidance from your customer regarding their specific control plan requirements. For an industry that strives for standardized work, this is a great step forward.
AIAG incorporated several lessons learned from the AIAG & VDA FMEA Handbook, but they also strayed from a typical AIAG document policy in one key area. Here are three of the lessons learned from this document, as well as AIAG’s noticeable variation from prior practices.
First AIAG & VDA FMEA Handbook provides a detailed explanation that will help the user base craft their documents. Identifying and explaining the control plan methodology is the most significant aspect of the new control plan reference guide, because for years, guidance for completing a control plan has been provided through institutional knowledge, customer feedback/direction, or third parties that were not involved in developing the control plan methodology. Absence of a standardized control plan methodology created an environment that allowed for interpretation and variation by each customer and supplier, creating variations in the quality of the plan and the document. The results of this variation were revealed through IATF 16949 audit results and quality issues.
The documented methodology is very specific, when necessary, and provides a framework for completing the control plan form and why this content is important. The sections outline the requirements and guidelines for completing each phase of the document, and these requirements and guidelines are based off solid manufacturing and quality processes. Best practices, including error proofing and “red rabbit” parts, are provided as typical tools that are expected of the automotive supply base. Thankfully, these concepts are not new to the industry, but it is beneficial to document these in a standard document.
Specific callouts are added to the guide to identify when it is appropriate to consult your customer with respect to their customer specific requirements. Removing the guesswork with respect to CSRs helps the organization standardize as much of their control plan process as possible and provides clear insight as to where the customer specific requirements come into play. Hopefully, this leads to future reductions in customer specific requirements for the supply base.
Credit to the writing team for not only articulating their intentions for control plan, but for explaining why these items are important. Explaining the why should reduce customer and auditor interpretations of how to do a control plan and allow suppliers – especially sub tier suppliers – greater clarity in the expectations required for a control plan. While the control plan document might not eliminate customer specific requirements, there is hope that the number of customer requirements might be reduced through these standard development guidelines. Remember, there are specific instances where the guide states to seek clarification from your customer, so there is an allowance for CSRs to affect control plan development.
The AIAG & VDA FMEA Handbook revision also included the identification of the responsible person to the control plan. As the only noticeable change to the control plan form, the addition of the “Responsible Person” column is significant in that it directs the team to the proper functional role that is required to lead the reaction plan and eliminate the opportunity to have the entire reaction plan be “Notify Supervisor.” From a functional perspective, providing this clarity allows the team to react faster to non-conformances and prevent these issues from growing out of control, while providing accountability to ensure the non-conformance is properly addressed. The bonus of directing the team to the functional title of the responsible party is that minimal changes will be needed to the document to compensate for positional turnover, eliminating making revisions for the sake of making a revision.
Lastly the addition of Family Control Plans into the control plan methodology is also notable. While functionally differs from how Family FMEA is described in the AIAG & VDA FMEA Handbook, the concept is similar: to group common content of similar parts into a family. In FMEA, the family FMEA is an input into the part specific FMEA. Where the control plan is different is that the family control plan is an end product that is accepted by the customer and treated as a standalone document.
Family control plans are used to manage common parts of different part numbers on one control plan document. The concept is not new, as family control plans have been used for parts that share identical features but are of a different color, as well as products, like catalytic converters, that are geometrically identical but have different internal components, none of which affect the manufacturing process. While they have been used, there has not been a common agreement as to how these will be used and that these family documents will be accepted by the customer. Thankfully, adding this feature to the control plan guide eliminates the variability regarding acceptance and allows the organization to use family control plans to reduce their document control complexity. The corresponding reduction in time to manage documents will be greatly appreciated by engineers, who no longer have to make repetitive control plan updates.
AIAG strayed from their policy by including a significant number of “must” statements in the new control plan guide. While most AIAG documents limit the use of the words “Shall” and “Must” in their documents because of their implications in auditing, the control plan guide has 58 “Must” statements in the 52 pages of guidance content in the book. In contrast, the 152 pages of guidance provided in the AIAG & VDA FMEA Handbook contains one “Shall” statement, which is in the VDA QMC copyright notice and 5 “must” statements. As “shall” and “must” are keywords in IATF 16949 auditing, the significant number of “must” statements open control plans up to many audit requirements. Will these statements increase or reduce the number of audit non-conformances, or will they improve the quality of the control plan? Many of these are in methodology, and how does one prove or disprove how they completed a behind the scenes task?
When considering the totality of AIAG’s Control Plan First Edition document, the guidance provided in the document will elevate the performance of control plans in the automotive industry, and this writer believes that will result in improved manufacturing processes and products. Providing specificity around a standard control plan methodology allows manufacturers to better manage their processes and not manage their customer specific requirements. This significant step toward standardized work eliminates much of the variation placed on the supply base, and allows these suppliers to focus more on process excellence and better document their process controls. It will be interesting to see what improvement will be noted through supplier performance and IATF audit non-conformances after the implementation of this updated methodology.
