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Says Peter Schmitt, VP of Marketing at Dassault Systèmes of America, "The $6 billion
loss at Airbus was the result of a fairly simple problem that could have been fixed with a
fairly low investment." His message was clear: Companies using PLM should make sure
they are using the same software package and version. "Manufacturers using PLM,"
Schmitt adds, "should make sure everybody is working with the same set of data."
Although Airbus has remained mum on exactly why the German designers used an older
CAD package, most observers believe the reason was simple Eurodollars and Eurocents.
The cost to train the engineers in Catia V5 may have been the sticking point for Airbus
that led to the A380's multibillion-Euro design flaw. That's the view of a firm that trains
Airbus' suppliers to use Catia. "Airbus made the decision not to migrate Germany to
Catia V5 because it would have meant a complete retraining," says Geoff Haines of Cenit
Ltd. in Oxford, England. "They decided not to do it for budgetary reasons."
So great is the chasm between the two versions that someone schooled in Catia V4 trying
to get up on V5 is similar to a motorist learning to fly an airplane. It takes six months to a
year before they become fully proficient, Haines says. "It would be like starting from
scratch," he adds. Those unfamiliar with CAD software may be wondering just how two
versions of the same software package could be incompatible, or for that matter, require
such extensive retraining. The reason is the two software editions differ in their basic
treatment of drawings, so the way digital models are created is different.
Both systems are able to represent objects in 3D, but that's where the similarities end.
Engineers using Catia V4 must use a manual process to create the geometry of a model.
To create a hole inside an object, the system requires them to subtract a cylinder from the
space to define where the hole should exist. The product designer using Catia V5 simply
feeds in a set of engineering instructions—describing the location and dimensions of the
hole—and the geometry is automatically created. "V5 is higher-level, more intuitive,"
says Doug Cheney, product manager for CAD interoperability at ITI TranscenData, a
developer of CAD translation software. "With the older system, the engineer figures out
the geometry; with the new one, the system finds the best geometric solution."
Airbus engineers ran afoul of this basic difference when creating the miles of wiring to be
inserted inside the A380 fuselage. The engineers' "notes"—appendices that describe
details of models such as curves—sometimes are not replicated in the translation
between Catia V4 and V5. In other words, key notes required to duplicate a 3D model
showing electrical wires as they twist and bend through the aircraft may fail to
reappear in full and accurate detail when a design file in one system is converted to a
file in the other.
For example, something basic such as the tolerance level of a metal part, noted by an
engineer in the appendix to a 3D drawing, may be left out when the model is converted
from one system to another. The result can be that the manufacturer—or a supplier—may
produce the part to the wrong tolerance.
In addition, units of measurement, when carried over from one CAD system to another,
can create havoc for designers, says Brian Barsamian, president of V5 Engineering, a
Newport Beach, Calif., firm that trains engineers to use Catia V5. "There was a complete
rewrite of the code from V4 to V5," he says. "You have to be careful to set parameters
defining whether you are exporting metric units or English units; otherwise, a 1
millimeter part can become 25.4 millimeters, because it sees 1 millimeter as 1 inch."
Still, most CAD vendors offer their customers a smooth path to convert their data from an
earlier version to a new one, according to Prawel. "Every vendor does a good job of
backward compatibility, except Dassault," he says. "Why some of the biggest aerospace
companies and automotive manufacturers in the world didn't force them to do a better job
of backward compatibility is a mystery to me. Now Airbus is paying the price." To solve
this problem, Prawel says many Dassault customers have decided to start from scratch
to re-create, or remaster, the data in all their existing models in Catia V5 because of its
lack of smooth interoperability with the earlier version.
Dassault owns up to the programs' dissimilarities, and the potential minefield they pose
for manufacturers adopting PLM midway into an upgrade cycle, or just trying to get the
　
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