What Grounded the Airbus A380?6 Dec, 2006 By: Kenneth Wong
Company management and CAD software both under fire in an interoperability debacle of jumbo proportions
Why isn't the Airbus A380 taking off on time? According to a variety of media, it's tangled in a bunch of electrical wire harnesses -- 530km of cables, 100,000 wires and 40,300 connectors, to be exact. According to Bloomberg.com, "[Airbus] engineers in Germany and Spain stuck with an earlier version of Paris-based Dassault Systemes' CATIA design software, even though the French and British offices had upgraded to CATIA 5. That meant the German teams couldn't add their design changes for the electrical wiring back into the common three-dimensional digital mockup being produced in Toulouse. ..." ("Airbus Vows Computers Will Speak Same Language After A380 Delay").
In blogs, aerospace insiders and CAD users picked up the topic where the press left off. Whether puzzled, outraged or bemused, most bloggers eventually get drawn into the same debate: Is the root cause the CAD modeling system or management oversight? (See "A380 Delay—Is It Really CATIA" at Airliners.net, "Disaster Stories" at WorldCAD Access, and "Lessons for All CAD Users" at AECnews.com.) According to some experts, it's both -- and it'll take both to prevent such debacles in the future.
Unused Industrial Strength
If Airbus were a smaller company, this issue would hardly be newsworthy. The interoperability plague is widespread, but more so among second- and third-tier manufacturers. Early this year, after surveying 571 such manufacturers, Kubotek, makers of KeyCreator, found data that provided insight on the extent of the problem: "By nature of their size, job shops have limited financial resources. Yet, their livelihood depends on being able to compete in today's complex multi-CAD environment. ... Not only do job shops have to deal with receiving, working with and sending files in disparate formats, but the majority have to do this for multiple clients...," says Robert Bean, chief operating officer of Kubotek USA ("Small Manufacturers, Big File-Exchange Issues," Cadalyst Daily, May 15, 2006).
As it happens, Airbus is an aerospace giant on the top of the food chain and the supply chain. And the interoperability issue identified in this case isn't a lack of compatibility between two different CAD systems; it's between two versions of the same CAD system.
Brian Shepherd, PTC's divisional vice-president, Product Management, remarks, "In my opinion, Dassault has not provided a reliable path for customers to move from the V4 architecture to the V5 architecture." PTC supplies Airbus with Windchill product lifecycle management solutions for the development of the A380 lines.
David Prawel, president and principal consultant at Longview Advisors, has a question for Dassault's biggest clients: "You are the biggest worldwide users of their products. How did you let them get away with not building a smooth transition from V4 to V5?"
In a written statement, Dassault responds, "Many of DS [Dassault Systemes] customers are working on long-term complex projects both with CATIA V4 and V5. Those with V4 and V5 running concurrently are perfectly happy with this, proving that the different versions work together perfectly well. DS' strategy with V5 has been to ensure, along with IBM, that any customers with V4 already in place migrate to V5 at their pace, in line with their long-term business projects. While joint V4/V5 projects work successfully, all our customers do see the interest of migrating from V4 to V5: the adoption of V5 since its introduction demonstrates the productivity benefits that customers achieve with V5. When customers are ready to upgrade, DS ensures they have the processes and modules necessary for a smooth transition from V4 to V5."
Questions Remain on CATIA's Role
In The Seattle Times report "EADS Execs pledge to Restore Confidence in Airbus, Fix A380 Problems," Airbus executive Tom Williams is quoted as saying, "One issue was that the CATIA computer tool used in the airplane's digital design was not sufficiently accurate when it came to designing electrical systems." Aviation Week's article, "New Management Eyes Big Changes for Airbus," similarly cites Williams: "Airbus officials say poor design tools were a main cause of A380 delays. Problems with the CATIA digital mock-up led to inaccuracies. Williams says the computer tool didn't represent the wiring harnesses well. ..."
Dassault public relations office says Williams informed them he had been misquoted, but won't provide further details. So is CATIA really at fault? AIAA's Jahadi cautions, "There has been a lot of speculation as to what really caused the problems. No one knows for sure except Airbus what the root cause really was."
Engineering to Management: Our Problem is Your Problem
Bloomberg.com reports, "As early as 1995, Airbus set out to streamline aircraft construction. The goal was to cut costs, reduce the amount of time between the conception of a new plane and its entry into service and better manage increasingly complex designs. It didn't manage to bring together the different computer technology."
In the same report, Charles Champion, the A380 program's one-time chief, is quoted as saying, "Attempts to have common tools failed for various reasons. It's all about legacy: When you start to use a tool, changing tools is an enormous investment. The question is always, what is the business case to change tools?"
So what is the cost of sidestepping this investment? An enormous loss of about US$6.1 billion over the next four years for Airbus, according to BBC ("Q&A: A380 Delays"). The estimate may need to be revised when order cancellations hit the company. According to BBC, FedEx is the first customer to jump ship.
Longview Advisors' Prawel points out, "Management must give more than lip service to the people who are trying to deal with the issues created by poor interoperability. ... The interoperability experts I speak with express frustration that their managers don't know about the problems and don't want to be bothered. Management wants interoperability problems to just go away. And, to add insult to injury, they don't fund things they don't care about."
Virtual Mockups and Real-World Risks
In a press release dated October 3, Airbus admits, "The root cause of the problem is the fact that the 3D digital mockup, which facilitates the design of the electrical harnesses installation, was implemented late and that the people working on it were in their learning curve." According to The Seattle Times, "The problem was made worse by Airbus' switch to aluminum wiring when the model was designed for copper wiring, which has very different physical properties" ("EADS Execs pledge to Restore Confidence in Airbus, Fix A380 Problems").
Mike Jahadi, chairperson of AIAA's (American Institute of Aeronautics and Astronautics) Computer Aided Enterprise Solutions Technical Committee and Lockheed Martin Aeronautics Company's senior manager of CAD/CAM Integration and Strategic Planning, explains, "The aluminum wire would have to have an approximately 50% larger cross section depending on the alloys used. This would make the harnesses stiffer and harder to manage in tight spaces. However, that would not make modeling them any harder or easier in V4 or V5. However, if the increased stiffness was not accounted for in the V4 design (manageable bend radii which is a user-controlled setting in V4), then I could see where you could get into trouble. In CATIA V5 you can assign different material properties to the bundles to account for increased or decreased stiffness. If the vendor in Germany was doing the harness routing in V4 within a V5 digital mockup, I could see how that could also be a problem, since you cannot read V5 parts into V4 unless the V5 parts are converted. That is one of the reasons that we have a converter on our programs at Lockheed Martin Aeronautics Company."
On Airliners.net, forum member Baron95 speculates, "If [Airbus] had stopped earlier, dedicated one airframe to be completely fitted with wiring (IFE [in-flight entertainment] and all), redesigned all parts, built another frame and tested the wire fitting, they'd be out of the woods now." We do not know whether Airbus in fact did this during the development.
Jahadi reveals, "At [Lockheed Martin], we replaced the physical mockups with the virtual mockups about 20 years ago. We do not use hard mockups any more." That means the virtual mockup must now stand in for the physical prototype for the required verification, simulation and testing. The more costly the physical prototype, the more likely a virtual digital prototype will be used.
Monitoring the Mockup
Is CAD ready to shoulder this burden? Perhaps, but the digital virtual mockup shouldn't be the be-all and the end-all. PTC's Shepherd suggests, "Do not just rely on the digital mockup -- it's a critical tool but not the answer to the overall process of design validation. On top of that, layer it with a change and configuration management system so you can quickly sort through the different variants you need to validate, and make sure the data you're working with is up-to-date."
Jahadi recommends, "Once the contract is awarded, you need to set up up-front how you are going to collaborate with your team members and suppliers, you need to have a central product data management system, define how you're going to use the digital mockup and how you'll exchange CAD data, and define how different team members are going to collaborate. Even with good coordination, it's still a challenge, but it's manageable. But without good coordination, it'll be a disaster."
PTC's Shepherd observes, "I think companies recognize that their customers expect them to carry the overall responsibility for the quality of the design." CAD can provide virtual prototyping tools and analysis tools, but in the end, it's up to the user -- in this case, Airbus -- to diligently watch the workflow and technology coordination.
The Silver Lining
To its credit, Airbus isn't dodging the bullet. Christian Streiff, who became CEO in July and inherited the floundering project, admits, "[It] is not the electrical design team of Hamburg who failed. Airbus is one company. It is Airbus as a whole which failed, the management on several levels with several passports who failed, and certainly not the teams on the shop floors." In October, he resigned, following in the footsteps of his predecessor, Gustav Humbert.
Kubotek's Bean says, "The Airbus problems underscore the enormous cost of poor interoperability across the entire global supply chain. This is only one incident of a growing challenge."
Is there a silver lining in all this? Longview Advisors' Prawel thinks so: "At least now, management will take interoperability seriously," he says. Prawel was a presenter at Boeing's Ninth Annual Product Data Exchange Conference, held recently in Mesa, Arizona.