Due to its safety-critical environment, the aerospace industry faces numerous compliance requirements demanded by the government and original equipment manufacturers (OEMs). Major aerospace OEMs require their suppliers to be certified according to EN 9100, a framework for the establishment of a quality management system for compliance with regulatory and customer requirements. With a strong focus on the surveillance and sustainability of key manufacturing processes, certification enables high product quality as well as market access.

However, companies often face various obstacles in order to reach certification standards. The implementation of most of EN 9100 requirements presents challenging tasks, as the standard documents do not provide concrete implementation strategies and are largely unspecific. Due to fewer human and financial resources, small- and medium-sized companies (SMEs) often struggle with certification. Consequently, they become unattractive as OEM suppliers and lose market access.

Funded by Germany’s Federal Ministry for Economic Affairs and Energy (BMWi), the Fraunhofer Institute of Production Technology has developed a systematic approach that instructs the establishment, control, and improvement of a company’s quality management system according to EN 9100, enabling certification according to this standard. The developed methodology has already been put into practice as part of the certification of Access e.V. according to EN 9100 for production of titanium aluminide turbine blades. Access e.V. is an institute for scientific research and development of materials and processes with a focus on metal casting.

6-step process

Companies can apply the following process when seeking EN 9100 certification (Figure 1, page 85).

1. Assess status quo

Research existing documentation to identify all actions necessary to fulfill the standard’s requirements. During this inspection, the quality manual, internal directives, form sheets, role descriptions as well as work, process, and testing instructions are examined. In this phase, the volume of information and number of different storage media of documents such as central databases, stationary desktop computers, or paper can be overwhelming. For economic reasons, it is generally advisable to split the examination into smaller portions carried out by those enterprise subsectors or subdivisions that are directly responsible or play a crucial role. In case of Access’ production of turbine blades, the scope of the investigation was narrowed down to part production and quality assurance.

2. Compare status quo, standard requirements

Once all relevant documents are at hand, the information must be collated and compared with the standard’s requirements. Establishing themed clusters helps analyze only those parts of the standard that are of concern for the particular scope. The comparison of specific requirements with company documents necessitates a suitable understanding of the standard. This again demands some expertise to avoid untrained personnel perceiving the wording used in the standard as too technical or obscure. The comparison process identifies discrepancies between the requirements of the standard and the company documentation. The standard’s requirements are labelled fulfilled, partly fulfilled, or not fulfilled. With partly- or not-fulfilled requirements, the related enterprise documents need to be clearly referenced, and companies should follow steps 3 through 6.

3. Action deduction

Necessary actions are deduced from the identified discrepancies between standard requirements and enterprise documentation. Extension and adjustment of the company documentation as well as a creation of missing documents need to be conducted where necessary. To ensure the achievement of the identified objectives, methods of quality assurance can be applied.

4. Action prioritization

Deduction is followed by a relevance weighting of the respective activities. First, decide which areas are of paramount importance and will be treated immediately. In the case of Access e.V., it turned out that core processes such as purchasing and project management, as well as key indicators for resource consumption and scrap rate, needed to be defined in detail. Secondly, the actions need to be further prioritized. Not- or partly-fulfilled requirements are divided into mandatory and optional, a categorization derived from the standard that allows scheduling implementation of required actions according to priority. Furthermore, conduct an expense and effort rating, which is especially beneficial in case of restricted capacity. It is important that the set of mandatory requirements is thorough and comprehensive, as failed implementation of mandatory requirements results in non-certification. Optional requirements can, however, be implemented later, such as during recertification. The implementation of optional requirements can, for example, achieve a more comprehensive documentation, improve accuracy of the inspection process, or reduce error potential.

5. Transfer into documentation

Specify and capture mandatory and optional requirements in the general specification sheet. When all mandatory and optional requirements are fully compiled and assigned to the related divisions, revise and reformulate the requirements to assure user-friendliness. The outcome is a comprehensive and tangible text that provides an intuitive overview of the requirements. Subsequently, transfer the determined requirements included in a general specification sheet into enterprise documents, such as test plans and process documentation.

In the case of Access e.V., the key process of quality assurance was graded top priority. As part of quality assurance, visual inspection and white-light interferometry were identified as the processes most prone to error, making them critical for certification. (Sidebar, page 86).

As inspection procedures vary depending on the respective product, process or objective, it is essential to derive specification sheets that are customized to each inspection procedure. Since test results must be independent of the executing personnel, test specifications and instructions need to be precise and unambiguous. A lack of clarity can have a strong impact on the testing results. Overly detailed specifications and redundancy need to be avoided as well. To ensure a transparent and traceable transfer of the standard into enterprise documentation, set general rules. Furthermore, the following five steps are advised:

  • Select general test plan, plan variant for related process
  • Identify characteristics specific to inspection process
  • Perform detailed analysis of characteristic effects on requirements for inspection process documentation
  • Transfer general specification sheet derived from standard to specific process requirements
  • Derive a final process-specific test plan

6. Auditing

Auditing evaluates existing structures of the management system, its documentation, and its actual execution by the personnel in daily business as well as compliance with the standard.

The cooperating partner, Access e.V., was audited after implementing EN 9100 using the described methodology and was found to be in full compliance with the standard, resulting in certification.

The method is independent of industrial sector, so it can be applied to standards other than EN 9100.

The project was funded by the Federal Ministry for Economic Affairs and Energy (BMWi), support code 20T1509B.

Access e.V.
www.access.rwth-aachen.de

Fraunhofer Institute for Production Technology (IPT)
www.ipt.fraunhofer.de/en

About the authors: Thomas Vollmer is an industrial engineer and head of Production Quality at Fraunhofer IPT in Aachen, Germany. He can be reached at thomas.vollmer@ipt.fraunhofer.de.

Dr. Matthias Bünck, head of Access e.V. Tech Center in Aachen, Germany, can be reached at m.buenck@access-technology.de.

Angela Niedermeyer, a mechanical engineer and Production Quality research associate at Fraunhofer IPT, can be reached at angela.niedermeyer@ipt.fraunhofer.de.

Tobias Schulte, a mechanical engineering faculty member at RWTH Aachen University, can be reached at tobias.schulte1@rwth-aachen.

Prof. Dr. Robert Schmitt is a professor at the Technical University of Aachen. He is head of the Chair for Metrology and Quality Management at the Laboratory for Machine Tools and Production Engineering (WZL).
He serves on the boards of directors of Fraunhofer Fraunhofer Institute for Production Technology and WZL and can be reached at r.schmitt@wzl.rwth-aachen.de.