Let’s take a close look at what APQP is. Note that it is not specific to product and process development and introduction alone. The last ‘Phase’ is ongoing production. This said, it is evident that despite the insinuation in the name (advanced planning) the APQP process addresses a continuous system from RFQ (Request for Quote) to the end of product life. It does not address ‘service’ parts. A large part of the APQP manual is devoted to lists of potential inputs and expected outputs. From phase to phase there are specified inputs and outputs. The output from Phase 1 is an input to Phase 2. The output from Phase 2 is an input to Phase 3 (etc.). A quick browse through the APQP and Control Plan manual reveals that at the beginning of each Phase these inputs and outputs are defined.
In order to address the issues of suppliers having different parts, different processes and thus often quite dissimilar systems, the APQP manual provides what are in essence ‘laundry lists’ of potential information sources for inputs. For example, in Phase 1 there is a required input of Voice of the Customer (APQP manual, page 7). The ‘laundry list’ for Voice of the Customer is on the bottom of page 7 (1.1 Voice of the Customer). You may have noticed that they give suggestions (inputs) of where to obtain this potential information sources (complaints, recommendations, various forms of customer feedback, etc.)
This is how the APQP and Control Plan manual graphically represents the process it describes. To a large degree, this can be looked at as Critical Paths in the process. You have to do planing before you do product and process design and development. You have to do product and process design and development before you can do product and process validation. Another way of saying this is to say the phases are Dependent. Each phase (except Phase 1) is dependent upon elements of (outputs from) the previous phase.
AIAG APQP & Ctrl Plan Reference Guide, Page 5
Advanced Product Quality Planning
There are Customer specific requirements in addition to the APQP and Control Plan manual requirements.