ICEM DDN Customer Testimonials

20,000 Safe Landings Every Day!
ICEM DDN has played an essential role in Messier-Dowty's design and production operations since 1984

The next time you see an Airbus, a Concorde, a Harrier or an F-18, it is likely you also will be looking at Messier-Dowty landing gear. Messier-Dowty has been designing aircraft landing gear systems for over 60 years and in 1996 had sales of US$400 million. It is the only manufacturer in the world which is able to produce fully-integrated, ready-to-fit, commercial and military systems in both Europe and North America.

Messier-Dowty International, the world leader in aircraft landing gear systems, is a joint venture between TI Group, UK, and Snecma Group of France. Six operational facilities, located in the United Kingdom, France, and Canada are responsible for the design, development, production, and testing of Messier-Dowty’s aircraft products. One in particular, situated near Lake Ontario on the outskirts of Toronto, in Canada, is the site of 18 ICEM DDN licenses. It is the place where centerline landing gear systems for the Airbus A340, the second largest commercial aircraft in the world, are designed and manufactured.

Collaboration from Concept to Manufacture
"We use the concurrent engineering approach here," states Paul Reynolds, CAD Design Supervisor at the Toronto facility. "Both the Design Department and the Production Department use ICEM DDN, and we have a shared database, making collaboration much easier." At Messier-Dowty, design is always the most important factor in building landing gear, but the company also is concerned with making sure the parts are manufactured in the most cost effective way. "We want to be sure the parts can be machined with NC programming and we try to eliminate any manual deburring," says Reynolds. "Sometimes Production can point out how a part might be designed so we can use tooling already in the shop."

The complete system is comprised of nearly 200 parts, including stabilizing links, retracting mechanism, piston, piston axle, seals, a nitrogen chamber and oil chamber. Most of the parts are cylindrical, which presents a greater design challenge than the more ordinary square surface.

Perfect match between the physical test numbers and the computer data
Reynolds believes the use of ICEM DDN by both the Design and Production Departments gives the company a great advantage. "It puts an end to the ‘recreating’ process and lets us build what we test," says Reynolds. "For instance, our models are built in ICEM DDN and then subjected to finite element analysis. That gives us a set of computer stress data. Later, when the actual part is built, it goes through a series of physical tests, including retraction, fatigue, and drop testing. What we want to see is a perfect match between the physical test numbers and the computer data. Then we know that what we designed is an exact model of what is manufactured."

Messier-Dowty also uses ICEM DDN as a check and balance for in-house manufacture as well as for sub-contractors. "Our production drawings are fully dimensioned with drawing notes, but they are still subject to interpretation. That’s why we also make surface model drawings. We know these are correct," explains Reynolds. "Actually, we do the surface model first and then the production drawing. Whenever something is unclear in the drawing, we check it against the model."

When designing a landing gear, Messier-Dowty addresses the physical issues first. To begin, the points on the aircraft, which indicate where the gea