Use of Modeling and Simulation in the Design of the Boeing 777 - Essay Example

Use of modeling and simulation in the design of the Boeing 777 Introduction The Boeing 777 is one of the most successful commercial airplanes made in the industry. The design process started in 1990 and the first plane was delivered in 1995, a remarkably short design period for a complex engineering product such as an airplane. Though the plane was initially designed for a production run of 300 planes, as of August 2013, over 1100 of these wide body airlines had been delivered.

Airlines continue to order these planes 17 years after the first production and the current production rate is 100 a year (Tinseth, Randy, 2013). The aircraft has also had an unblemished safety record and even the crash of the Asiana Airlines plane at San Francisco airport in July 2013 has been attributed to pilot error. The aircraft industry design process has been described as “design- mockup- rework-protoype-test-revise-produce-test-revise-produce-test”cycle (Snyder, Charles, R.

, et al, 1998, p34). Boeing 777 design process was dramatically different from earlier practice in the airline industry. 2. The Boeing 777 Design process Wolf L. Glende, the Chief Engineer – Systems of the Boeing 777 programme says that the plane was conceived as a model urgently needed to fill the gap between the 747 and the 767. The design target was a plane that could carry 300 and 500 passengers over distances up to 7500 nautical miles at a cruise speed of 0.84 mach. The Boeing 777 was the first commercial airplane designed with active participation from its customers.

Boeing worked with eight major airlines from the US, Europe and South East Asia to configure the plane they preferred (Glende, Wolf, L., p 5-2). One key objective was to reduce by at least 50% the change, error and rework that is typical of large engineering system design projects. These objectives were achieved by adoption of certain core processes discussed below (Glende, Wolf, L., p 5-3). a) Design/ Build Teams Design of a large airplane involves large teams, employed with different organizations and at various locations.

Design activities tend to be done in series with results “thrown over the fence” with incomplete communication. The job specialization of each time makes for incomplete understanding and inter-organization rivalry. For the 777, Boeing created multi-functional Design/Build Teams (DBT) for each major subsystem of the airplane such as Structures, Avionics, Mechanical/Hydraulics, Propulsion and Payload. Each DBT included representatives from various functions such as Engineering for product definition, Manufacturing for tools, fabrication and assembly, Materials for procurement, Customer Services for training, spares and maintenance issues, Quality Assurance and Finance for design to cost issues.

Supplier and airline representatives were included as needed. At the peak of the design phase, Boeing had 238 such Design/Build teams. Once each subsystem from the DBTs neared completion, new teams named Manufacturing Integration Teams were formed to get integrate the subsystems into the whole airplane (Glende, Wolf, L., p 5-4). The Design/Build teaming led to the Boeing organization changing from separation of functions to team orientation and from a culture of individual brilliance to knowledge sharing (Snyder, Charles, R.

, et al, 1998, pp32-33). b) Digital Product Definition The Boeing 777 was the first airplane to be entirely designed on 3D CATIA software. Over 2200 individual workstations were connected to 8 mainframe computers in Seattle with additional links to Philadelphia and Wichita in the US and to Nagoya in Japan. From Nagoya, links were established to manufacturing plants of Kawasaki, Fuji and Mitsubishi who were major system suppliers. Connections were also established with the engine suppliers GE, Pratt & Whitney and Rolls Royce.

On average each week 5000 files with 12 GB of CAD data was exchanged on this network (Snyder, Charles, R., et al, 1998, p34). Each engineer had to develop preliminary concepts and even sketches on the CAD platform that was continuously accessible to the entire team. All changes to the concept had to be done on the same CAD model which allowed other engineers to see how their own parts would fit in. The CAD model also generated data such as materials used, stress, loading and weight. This data was used by other team members to examine issues like tool design and training (Glende, Wolf, L., p 5-5). c) Digital Preassembly Digital preassembly is the process which replaced the need to make physical mockups to see how the different subsystems integrated into the airplane design.

This was accomplished by the EPIC system (for Electronic Preassembly in Computer) designed by Boeing themselves. The CATIA models of individual components and subsystems would be built up into the aircraft model and the engineers could visualize issues like fits and tolerances, access for assembly and dismantling, routing of cables and pipes and other such details which were done with physical mockups earlier. In the earlier traditional design process, there were 3 levels of mockups and the component or subsystem engineer had to freeze his design in these 3 attempts.

With the EPIC system, he could fine tune his design multiple times until there was a “freeze” to permit the tooling or manufacturing engineers to proceed with their design activity. The EPIC system together with the CATIA models also helped the 777 designers to reduce variety of parts by 25% by using parts already designed for another subassembly (Snyder, Charles, R., et al, 1998, p35). Boeing also utilized a Knowledge Based Engineering (KBE) system from Concentra Inc. with in conjunction with code developed by Boeing in-house.

This system checked the evolving design of the plane to known rules and standards to ensure that there were no violations. For example, the FAA rules on final stress analysis were part of the KBE system ensuring that no component design would violate those limits. Similarly computer simulations of passenger seating and aisle clearances were applied at all stages to ensure that these did not end up requiring rework of design (Miller, David, E., 1998). d) Enhanced Validation The improvements in the design and product realization phase of the design project required to be matched by validation of the designs at an early stage so that there are no failures encountered in testing.

Boeing created a $ 370 million Integrated Aircraft systems laboratory to simulate full flight conditions on the ground. A total of 57 major aircraft systems, 3,500 line replaceable units and 20,000 parts were tested and integrated into the aircraft design. Complementary use of wind tunnel tests with CFD (Computational Fluid Dynamics) analysis resulted in better wing design than in previous planes. The number of wind tunnel tests could be reduced from 77 to 38 (Ball, Doug, 2008).

The aircraft had to be certified with each of its three makes of engines. The test programme simulated 1,000 cycles of take-offs and landings under various weather conditions using computer simulation. This elaborate testing plan helped in the 777 being cleared for ETOP (extended range twin operations) for intercontinental and over the ocean flights by both the US and European aviation authorities. These lab facilities also helped reduce the training time for aircraft mechanics from 75 days to 49 days (Snyder, Charles, R.

, et al, 1998, pp37-38). 3. In summary, The Boeing 777 design process adopted has truly revolutionized the process of design not only in the aircraft industry but also for other large engineered products and even projects. The use of 3D Computer Aided Design tools and cross functional design teams to speed up the product realization process have now become common practice. ­­­­* * * *References:1. Ball, Doug. “The use of Modeling and Simulation at Boeing Commercial Planes”, Sept 2008.

(Accessed on 27 Sept 2013 at www. sandia.gov) 2. Glende, Wolf, L. “The Boeing 777: A Look Back”, AGARD FVP Symposium, Norway, 22-25 Sept 1997. (Accessed on 27 Sept 2013 at http://ftp.rta.nato.int/)3. Miller, David, E. “Modeling and Simulation Technology, a New Vector for flight test”, Maxwell Air Force Base, Alabama, June 1998. (Accessed on 27 Sept 2013 at www.dtic.mil). 4. Snyder, Charles R., Snyder, Charles, A. and Sankar, Chetan, S. “Use of Information Technologies in the process of building the Boeing 777”, Journal of Information Technology Management , Volume IX, No 3, 1998.

(Accessed on 27 Sept 2013 at www.jitm.ubalt.edu)5. Tinseth, Randy. “New heights for the 777”, Randy’s Journal, Boeing, 25 Feb 2013. (Accessed on 27 Sept 2013 at www. boeingblogs.com).