Data management matters

SAE International’s director of new product development & portfolio management, Audra Ziegenfuss looks at how best to integrate digital standards into modern aircraft development.

A digital thread is a communication framework that connects separate elements, such as those from design and manufacturing processes, of a product through the course of its lifecycle to enable communication and collaboration among the participants.

In the development of the T-7 Red Hawk trainer aircraft, for example, Boeing, in partnership with Saab, employed a digital thread process to design, test and build both the hardware and software systems. This process, according to the companies, produced a 75% increase in first-time engineering quality, allowed an 80% reduction in assembly hours, and led to a 50% reduction in time spent on software development and verification.

Outcomes like this are being noticed by companies and procurement agencies eager to implement similar strategies to optimise operational efficiencies, support novel technology and product development, and improve cost synergies in future development programmes.

Development and production of modern aircraft, like the T-7, would be impossible without easily accessible and up-to-date engineering standards. The distribution of these standards has evolved over time from print to PDF or EPUB formats. These formats, however, are proving to be inadequate for easy consumption by electronic endpoints that aim to integrate standards more easily within the complete product lifecycle - from design to maintenance.

SAE International is a standards development organisation (SDO) that works closely with the aerospace industry to develop robust standards tools with highly integrated usage. Given a standard’s richness of content, the number in circulation and development, plus the diverse document structures, formats and purposes, SAE International maintains that a single format approach will not be adequate to support how industry needs to use and apply standards in the digital era. This will require a digital standards system with a multi-faceted approach.

A quick history

The format of standards has evolved from one for print-based distribution, to one using Extensible Markup Language (XML) in document production, with many SDOs now converting their legacy documents. XML uses a set of ‘tags’ to structure a document so it can be read by a machine and this is one of the ways an organisation can keep track of the changes in a document, like a standard. A structured, machine-readable format coupled with a content management system can mean greater functionality when published on a digital distribution platform, such as a SAE Mobilus digital platform.

A strong digital standards system, however, will be able to support many inputs, of which XML is only one. Once a digital standards system is in place, standards should be developed within that system of which XML inputs is a part.

Key considerations

The implementation of a dynamic digital standards system, one that is highly integrated with multiple engineering applications, needs to be driven by several key considerations, including the following:

• Normalisation - provides a common approach to defining different parts of a document, using an existing reference model or one in development. By using XML as one potential input to this system, an organisation will be able to connect standards to its processes and products.


• Data ownership - how can the data housed in standards, and transmitted by an organisation in third party documents, be source-traced in a potential audit and verified for accuracy and up-to-date status? Developers need to know the data end points, how content will be accessed, integrated and how terms will be enforced.


• Interoperability - standards and the information within them are put to use in every product lifecycle management (PLM) stage, so the information in the standard should be accessible by and interoperable with the PLM platform, the tools used by engineers in their design and development, and others within the supply chain.


• Flexibility and scalability - any digital standards system needs to be flexible to allow for inputs from multiple data sources and formats, and scalable enough to change as new technologies and improvements are introduced, which will require documents to change accordingly.


• Costs - in order to avoid document maintenance and conversion costs to support XML, there needs to be cooperation between the industry, SDOs, and software vendors. Standards often contain a blend of text, tables and data, and different formatting of this data between standards can make data location difficult. The use of databases that are designed to scale horizontally can keep these costs in check.


• Document Types - a digital standard XML-based system should be able to accommodate both data-centric standards (data heavy) and document-centric standards (data lite).


• Maturity - evolving database technologies that allow queries against large numbers of XML documents are being developed, but are not yet mature. To accommodate for the evolving state of these technologies, hybrid approaches to digital standards system development will be required to mitigate risk yet provide flexibility.


• Performance and concurrency control - concurrency is when several tasks overlap in execution in a system, or when multiple computations are happening at the same time. Concurrency control then seeks to schedule transactions and maintain serial order. With the volume of standards used in transportation, and the complexity of queries on those standards, performance could suffer. Any digital standards system will have to consider the type of database being used to store content, whether in XML or otherwise.


• Transaction management and auditing - when moving to a digital standards system using XML or a database extracted from XML, error corrections are to be expected. Users should be notified of database errors in, or changes to a document due to updates or revision, and an audit trail should be available for review.


• Change management - without the means to monitor and communicate changes in a document to its users, a digital standards system would be functionally static and less useful. Standards are updated over time, so if a standard’s information is integrated within, or referenced by, a secondary document, its information must be maintained.

With progress comes challenges. The success of digital thread strategies to optimise efficiencies within the aerospace product lifecycle system has focused companies on their ability to realise productivity gains in product concept, design, testing, manufacturing and maintenance.

Industry standards are pools of knowledge that are critical to all facets of the aerospace industry and part of any digital thread strategy. The development of a digital standards system within an enterprise allows standards to be efficiently communicated, updated, revised and tracked.

The formatting of standards needs to evolve to support digital thread initiatives. Independent SDOs, along with companies developing their own internal standards, are working on optimal ways to format standards and the data they contain to allow their intelligent use throughout the entire value chain of an organisation. SAE International, a pioneer in standards technology, recommends a multi-faceted approach to a digital standards system that supports highly-integrated standards usage.

Audra Ziegenfuss is the director of new product development & portfolio management at SAE International. She recently published a whitepaper titled ‘Digital Standards Systems - An Integrated Approach to Engineering Standards Usage.’

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