Using XML to Enable Low-Cost Deployment of Content at Lockheed Martin Aeronautics

Lockheed Martin Aeronautics, a business unit of Lockheed Martin Corporation, is a key supplier to the Department of Defence for major aerospace programs, including the F-117 stealth fighter, the U-2 surveillance aircraft, and the new F-22 air superiority fighter.

The F-117 stealth fighter has been in service for more than 20 years. It has demonstrated its effectiveness in extensive combat missions in a variety of combat theatres. Continuing upgrades to the aircraft along with changing approaches to staffing flightline technician positions led to new priorities for the aircraft maintenance and repair documentation. The program needed faster updates to manuals, electronic manuals with minimal deployment cost, an ability to ensure conformance to procedures, and an ability to integrate with external systems. All these goals needed to be addressed within challenging time and budget pressures.

The maintenance, repair and upgrades of the F-117 require comprehensive procedural content. And the consequences of the documentation failing to properly convey the correct information are high; people's lives are at risk if maintenance information is inadequate or incorrect. The total volume of content is high for the size of the F-117 program, consisting of tens of thousands of pages of traditional paper documentation. The procedures themselves are complex and detailed, as with any complex equipment. They have many cross-references to other information and other systems, including parts catalogues, and contain a significant amount of ancillary information, such as cautions and warnings that must be placed in the documentation in such a way as to ensure that technicians see the warnings before executing the steps they refer to. In general, this kind of content creates an implicit requirement for “rich” content, with a significant amount of re-use and re-purposing of information.

In addition to the complexity and risks associated with any maintenance equipment for complex equipment, the F-117 program had new challenges. For most of its history, the F-117 Program had its choice of personnel, many of whom had stayed with the program for a large part of their military careers. Policy changes around the program had recently made most of the F-117 personnel subject to a more typical rotation, in which technicians would be rotating “through” the program for two to three years. This put a new burden on the maintenance information, since prior to this, technicians typically had many years of experience on the aircraft, and could supplement the maintenance procedures with their own expertise. With a more typical experience profile for technicians, the Program wanted to make the maintenance information more self-sufficient, and to be able to ensure conformance to the published procedures.

Another growing challenge faced by the Program was the increasing expectations for faster and cheaper delivery of maintenance documentation changes. The Program had strict guidelines and processes for distributing updates to the field, including processes for Rapid-Action Changes, where critical information needs to be distributed as quickly as possible to all F-117 service personnel. The Department of Defense (DOD) and the Air Force wanted new, faster methods for deploying maintenance information for both regular updates and Rapid-Action Changes, and were very interested in electronic manuals as a key part of those processes.

Distribution of electronic maintenance manuals had to accommodate two key criteria: a guarantee of the security of the information, and a minimal cost (preferably zero) for software required to access the information. In addition, the value of electronic information would be substantially higher in DOD's and the Air Force's eyes if the information could be easily linked to new online services, which are in the process of being discussed, such as parts inventory and ordering systems.

All of these changed and changing needs were impacting the Technical Publications group for the Program, which had been working for many years with paper-based processes for making documentation changes, with a separate Production group being responsible for producing paper change pages using Interleaf.

The Publications group determined that they needed a fresh look at their technology infrastructure and processes to meet the changed and changing needs of the Program. They contracted with Calian, a large systems integrator with key expertise in content management, to explore alternatives and implement a new XML-based systems infrastructure for creating and producing documentation.

Based on the scope of the requirements, and with the extensive involvement of key staff in the Technical Publications group, a decision was made to proceed with a project with four key goals:

• Develop the core functionality of an end-to-end content management solution.

• Prototype an electronic manual usable on the flightline with low-cost deployment.

• Validate the technical, business and content requirements and risks.

• Automate paper manual production.

The resulting solutions architecture for the project follows a functional organization standardized by Calian and Luoma & Associates for content management solutions. This generalized solution architecture addresses the separation of infrastructure layers from the application functionality, as described in the following diagram:

Content Creation & Capture

This functional area includes such aspects of a system as what source file types and authoring tools are supported, and what types of integration are necessary for capturing items like metadata and link information. As well, this functionality includes the interface mechanisms for adding content to the repository.

Storage & Management

This functional area focuses on the content repository, especially two key services: Library Services and Repository Services. Library Services includes such things as check-in / check-out, version control, and metadata management. Repository Services includes aspects such as user and account management, authentication, and access control

Assembly

This functional area involves the processes and techniques for aggregating and organizing information to meet specific target audience needs.

Production

This functional area manages the formatting and presentation of content.

Deployment

This functional area includes the tools and interfaces for accessing information from the perspective of the end “consumer” of the information.

Navigation & Search

This functional area provides the interfaces and capabilities for users to find content, including both navigation (“drill-down” hierarchies like a nested table of contents) and search (fulltext and attribute). The interfaces for this functional area may be substantially different for different types of users, for example, content authors versus “consumers” of the content.

Information Management

This functional area provides the interfaces and methods for capturing, managing, and using metadata about the content. This layer should be based on information management standards appropriate to the organization and the content, and is critical in developing effective navigation and search interfaces.

Architectures & Technical Standards

Any content management solution must be built on the foundation principles of the architectures and technical standards in place within the organization, the industry, or the contractual relationships with the customer.

For the F-117 Program, the Technical Publications group worked with Calian and Luoma & Associates to identify the most appropriate tools and technologies to satisfy the solutions architecture. Those decisions are summarized in the following diagram:

The product choices were driven to a large extent by the architectures and standards issues, which involved XML and SGML. Early in the project, the decision was made to focus on authoring of “rich” content that would support the requirements for content re-use and re-purposing, as well as extensive linking and automation. A number of XML/SGML standards were chosen:

AECMA 1000D	An SGML standard chosen for its rich content markup of aviation-related procedural information.
ATA 100 Numbering Scheme	A commercial aviation standard that provided the essential metadata and organizational architecture of the information.
MIL 1808 SSSN	The military system/subsystem/sub-subsystem approach to organizing information about complex equipment.

In addition, the project had to meet the DOD requirement to delivery paper documentation in accordance with the JCALS 38784 standard, which governs the formatting and presentation of paper-based information.

Given these architectural underpinnings, it was clear that the content management solution needed to support XML and SGML through most, if not all, functional areas. As well, a significant implication of these standards was the ability to create, manage and assemble maintenance information at a “granular” level, which was a primary driver for the choice of a fully XML/SGML-enabled content repository product.

These early choices also guaranteed that the solution would be able to meet the full range of requirements for the content, including:

• Content re-use and re-purposing, including automated assembly and transformation of XML/SGML content for paper and electronic manuals.

• Potential for integration with external systems, such as an Illustrated Parts Breakdown (IPB), parts inventory and ordering systems, eLearning and training certification systems, and aircraft life-cycle tracking systems.

A further benefit of the XML/SGML architecture of the system was to provide a vendor-independent storage format for content, so the Program could not be held hostage to a proprietary system, or face huge conversion costs in the distant future.

The next major analysis and design aspect of the project concerned the architecture and design of the electronic manual. The decision was made to develop a formal Interactive Electronic Technical Manual (IETM). The goal of an IETM is to provide all the information a technician needs, the way he or she needs it. To achieve this, the IETM must be sufficiently useful and usable to eliminate the need for common practices for using paper-based manuals, including personal “black books”, sticky notes and margin annotations. This level of usability is difficult to achieve in an interface that appeals to an audience that is focused almost exclusively on the information itself.

The project team adopted an iterative design, develop, test approach to implementing the User Interface (UI) of the IETM. The following screen illustrates a few of the key outcomes of the design:

This UI delivered the usability, linking and integration capabilities that DOD and the Air Force wanted, with an expectation that the IETM would provide a significant improvement in conformance and speed of equipment maintenance.

The high-level architecture of the IETM is relatively straightforward, as it is based on delivering XML content to Internet Explorer (version 5 and higher). The IETM is delivered as a simple set of directories and files on a CD-ROM, which meets the Air Force requirements for the physical security of the information. JavaScript modules are used for programmatic and interactive features of the interface. Only one browser plug-in is required, for display of the CGM graphics. The following diagram summarizes the high-level architecture of the IETM:

This architecture uses XML to achieve the following benefits:

• No manual HTML tagging. XML content is formatted on-the-fly with XSLT transforms and XSL stylesheets.

• Automated link generation. Links are generated from the SGML/XML content using a Topic Map approach.

• Automation of IETM production. Many aspects of the production of the XML files for the IETM are triggered programmatically by the tags in the content.

• Demonstrated potential for programmatic integration of custom functions and links to external systems. The use of rich XML content in the browser enables programs to use the XML Document Object Model (DOM) in JavaScript to execute custom code and initiate or process transactions with other systems based on the tags in the content.

Overall, the project was deemed to be a tremendous success by all stakeholders. Technically, the feasibility of using a rich content architecture and XML deployment through Internet Explorer was conclusively demonstrated. Other key technical approaches, including the use of XSLT and Topic-Map based linking, were successful, and generated ideas for future enhancements to the IETM.

From a project perspective, a key successful decision was to focus on a high-functionality repository product to provide as much of the core functionality as possible, lowering systems integration and product licensing expenses. As well, the iterative approach to the design of the IETM's UI was a key success factor. Finally, the success of the project was dependent on the successful joining of Calian and Lockheed Martin personnel into a single implementation team.

While the project was successful, there were a number of challenges encountered by the project team that are illustrative of the challenges many organizations will face in similar projects.

XML standards and products are evolving quickly	This creates a moving target for implementation teams with specific schedules and deliverables. Especially with the IETM, the project team had to redesign or re-engineer components to account for changes to Internet Explorer and its XSL and XSLT handling, and to changes in the evolving XPATH and XLINK standards.
Developing browser-based IETMs requires breaking new trails	There are many different ways to implement advanced IETM functionality in a browser, and there are few standards or guidelines that provide models that can be followed.
Print isn't going away	While the focus of many content management solutions for maintenance documentation is on electronic information delivery, traditional paper documentation is still a requirement for the short and medium term. The use of paper documentation will drop off over time, but will likely be required for the foreseeable future.
Legacy content conversion requires a significant investment	No matter how standardized the use of proprietary tools, the difficulties of converting proprietary legacy content into SGML/XML is easy to underestimate. It is useful to plan the conversion effort strategically, with a separate business case and Return On Investment (ROI) expectations.

Based on the F-117 project, XML provides a rich, robust standard on which to base many content management solutions targeted at maintenance information, paper and electronic. With the XML capabilities embodied in the newer browsers, it is unquestionably feasible to implement advanced interfaces based on XML, with low development costs and minimal-cost deployment. In the case of the IETM, XML was essential to automating UI functionality without extensive custom programming or a proprietary viewer.

Design and Development by deepX Ltd.