Figure 17.2. Aircraft cost factors of the worked-out Bizjet example

stock, training, and maintenance costs can be shared. Private ownership in this class is increasing and there is room for both types.

However, modifications to the smaller variant can improve the index Kn smaller. If re-engined with a smaller turbofan (i.e., the Williams type) and re-engineered with lighter and less expensive equipment, the aircraft price could be decreased to about $5 million, making it even more attractive; however, it loses some component commonality and incurs additional development costs. If the wing tips can be shortened at practically no extra cost, then the weight can be decreased to less than 7,000 kg, and the index can reach a value of more than 1.

Design for customer can help manufacturers establish the aircraft price for a family of variants, giving each type a comparative value for the customer. Typically, the smaller variant should be priced lower with a smaller profit; other aircraft prices are adjusted, with the baseline aircraft price unchanged. That is, the price of the larger aircraft can be increased to compensate the family price structure. The goal of the baseline size is maximum sales. In the example, the price of the smaller variant is $6 million, resulting in a small profit. The baseline aircraft aims for the most sales to maximize profit.

In general, route traffic load continues to increase; consequently, sales of the larger variant also increase and also the associated profits for the manufacturer, making up for the relatively smaller profit from the smaller variants. When a new market emerges for a larger traffic load, manufacturers seize the opportunity for a new baseline design.

The aircraft price per passenger and unit mass are explained herein. There is a sharp increase in per-passenger price with a smaller payload, as shown in Figure 17.2. In the figure, the dashed lines represent generic data; it is a magnified version of Figure 16.2. The solid lines represent the Bizjet family. The smaller aircraft price is slightly depressed to suit the market.

17.10 Digital Manufacturing Process Management

The digital manufacturing process management is a newer concept and is still evolving; it is software-driven. Although the industry has already deployed digital

manufacturing in some areas, the full scope of application is yet to stabilize. This section describes a model briefly studied at the QUB [7]. It outlines the nature of changes taking place. These types of studies are conducted in many places, proposing many different models. The core fact is that digital manufacture is here to stay, grow, and replace or merge with traditional manufacturing philosophies.

Today, the microprocessor-driven digital manufacturing process is rapidly overtaking older methods. In fact, all modern production plants are already using it to the extent that it can be advanced. The advantage of microprocessor-based tools is that they are digitally controlled and driven by software. These tools deliver the desired “quantum leap” in manufacturing assembly techniques for future aircraft. This section outlines the role of MPM and identifies the benefits of PLM through the reconciliation perspective (i.e., estimation versus actual) between design and manufacturing engineering disciplines. PLM is a business strategy and part of MPM as a management strategy. (Life cycle is used in a generic sense, meaning all aspects of a product, from concept to retirement.)

Digital-manufacturing solutions enable the continuous creation and validation of the manufacturing processes throughout a product’s life cycle. It allows manufacturers to digitally plan, create, monitor, and control production and maintenance processes, providing complete coverage of the manufacturing processes. With the advent of new processes and techniques, there has been a greater use of software in the design and engineering of aircraft. CAD, CAM, CAE, and CAPP tools are now used to determine electronically how an aircraft system must be built. NC machines are linked with CAM.

The new frontier with software suites focuses on PLM, emphasizing the manufacturing processes. PLM is a business strategy that allows companies to share product data, apply common processes, and leverage corporate knowledge to develop products from conception to retirement across the extended enterprise. By including all participants in this process (i.e., company departments, business partners, suppliers, and operators and customers), PLM enables the entire network to operate as a single entity to conceptualize, design, build, and support products.

MPM is segmented into process detailing and validation, resource modeling, and process planning simulation. Within each segment are several modules, discussed as follows.

Process Detailing and Validation

This software suite provides engineers with the tools to bring the process planning solutions into the application-specific disciplines of manufacturing. It assists engineers in verifying process methodologies with actual product geometry and defining processes within a 3D environment. The human module offers tools that allow users to manipulate accurate, standard, digital, human mannequins, referred to as “workers,” and to simulate task activities in the process-simulation environment. Thus, worker processes can be analyzed early in the manufacturing and assembly life cycle. The assembly process simulation module sets a new paradigm for developing manufacturing and maintenance processes. It offers manufacturing engineers and assembly process planners an end-to-end solution by incorporating a single, unified interface for preplanning, detailed planning, process verification, and shop-floor instructions.

design and manufacturing planning before a release is final. When this is possible, manufacturing producibility analysis directly influences design, thus providing a true DFM/A environment. In this scenario, the total costs of the engineering changes that occur during the program are dramatically less because they are identified and resolved much earlier in the life cycle. The total effective cost of the changes is dramatically less because they are mostly identified and resolved before tooling is procured and production starts.

The key technology enabler for the digital manufacturing solution, product/process design, and validation is the PPR hub and business transformation. This database environment – supporting complex configuration and affectivity rules that are required in the aerospace world – provides the infrastructure to allow process and resource planning to occur in the context of the engineering data and continuously changing environment. In contrast to traditional systems, the PPR hub provides the means to explicitly manage PPR objects and the relationships among them. Because such relationships are explicitly defined and managed within the database, it is possible to see directly the impact of changes of one object class on any other (e.g., “If a part is changed, which manufacturing plans are affected?”).

17.10.2 Integration of CAD/CAM, Manufacturing, Operations,

and In-Service Domains

One of the major areas for improvement within an aerospace enterprise is in the integration among engineering, manufacturing, and operations organizations. The drivers for such integration are to allow the maximum reuse and appropriate consolidation of data and business systems throughout the program life cycle. The degree to which this is achieved typically has a major influence on overall costs, both recurring and nonrecurring. Traditionally, the engineering and manufacturing (i.e., CAD and CAM) domains operate in a self-contained operating unit. As a result, it is difficult – if not impossible – to actually leverage engineering data downstream in the shop-floor operations area where typically bills of material (BOMs) are defined, along with related procurement data and shop-floor work instructions. One major problem with this traditional scenario is that effectively managing engineering changes and reconciling the parallel worlds of CAD and CAM and shopfloor operations is extremely difficult and expensive to do accurately. Digital manufacturing provides a means to integrate these two domains (i.e., CAD/CAM and operations), as well as the in-service domain, through several core technologies and application layers.

An additional benefit of this type of integration is the ability to reduce the number of redundant business systems between the CAD/CAM and operations organizations. This reduces recurring and overhead costs. Specifically, the following classes of business systems can be consolidated into the PPR-hub–based solution suite:

parts list and tool list

BOM definition

bill of resources

routings

process sheets/work instructions