Collaborative research and development project on composite bonded wing box

The research and development project “Composite Bonded Wing Box” was an unprecedented collaborative effort between Canadian companies, universities and government agencies. The industrial partnership, led by Bell Helicopter Textron Canada Ltd., included Pratt & Whitney Canada Ltd. and Delastek Ltd., a small to medium-sized entreprise (SME) located in Grand-Mère, Que.

The university partnership consisted of Concordia University as the lead, and École Polytechnique de Montréal. The primary government partner was the Institute for Aerospace Research in Ottawa and its Aerospace Manufacturing Technology Center in Montreal.

Other participants were Bell Helicopter Textron Texas and Defense Research Establishment Valcartier. Funding was provided by CRIAQ (Consortium for Research and Innovation in Aerospace in Quebec), participating industrial partners and the Canadian federal government. In-kind support was provided by the National Research Council of Canada and university partners. The total value of the project was more than $2 million (Canadian) over a period of 2.5 years (July 2003 through December 2005).

The objective of the project was to develop composite components for a wing box where composite ribs are bonded (rather than bolted) to the composite wing skin. Resin transfer molding (RTM) was to be used to assure good surface finish for the rib chords.

In 2003, there was no Canadian expertise in aircraft-quality resin transfer molding of composites. At the time, Delastek Ltd. was a small company with experience in manufacturing composite parts for non-aircraft applications, such as boats, pipes and industrial-grade components. Even though large aircraft companies in Canada such as Bell Helicopter Textron Canada Ltd. and Bombardier Ltd. were making and using composite components, there was no SME with the capability to supply composite components to the OEM.

It was recognized that the existence of such an SME would be critical to the supply chain. Delastek Ltd. therefore entered into the project with the hope that it would transform itself from a “low-tech” supplier to a “high-tech” supplier capable of supporting the larger companies.
Project tasks were distributed among the partners as follows:

1. Bell Helicopter Textron Canada Ltd. (Dr. R. Fews) was responsible for the overall project. Bell Helicopter would lead on the manufacturing of the upper skin, lower skin and the assembly of the final wing box.

2. Concordia University (Dr. S. Hoa) was responsible for the design and analysis of the wing box subject to static and dynamic loads, and to design the load introduction hardware.

3. Delastek Ltd. (C. Lessard) was responsible for the design and fabrication of the mold for resin transfer molding of the rib chords.

4. École Polytechnique (Dr. F. Trochu) was responsible for the flow modeling of the resin transfer molding process.

5. Aerospace Manufacturing Technology Center (Dr. M. Hojjati) was responsible for the manufacturing of the rib chords using resin transfer molding.

6. National Research Council of Canada Institute for Aeropace Research (Dr. J. Laliberté) was responsible for the bonding of the rib chords to the wing skins.

7. Defense Research Establishment Valcartier (Dr. D. Nandlall) was responsible for the calculation of the response of the wing box due to ballistic impact.

8. Pratt & Whitney Canada Ltd. (Mr. S. Caulfield) would like to obtain knowledge from the response of composites subject to impact load.

Through these efforts, Delastek Ltd. developed expertise in the resin transfer molding process for aerospace applications. The company also manufactured the mold.

The project was a huge success. The composite wing box panel was shipped to the U.S. in November 2005 for testing. The universities had an opportunity to work with the companies and learn how industry does business.

This cooperation contributes significantly to an understanding of time scale expectations that subsequently facilitates future collaboration between universities and companies, particularly for the training of students.

The two labs at the National Research Council of Canada had an opportunity to work on an industrial scale project. Both had a jump in their technology. New major pieces of equipment (worth million of dollars) for composite manufacturing have been acquired thanks to the success of this project.

Bell Helicopter obtained a bonded composite wing box for testing for performance under ballistic impact. Bell also developed a relationship with an SME (Delastek) that can now manufacture composite components suitable for Bell’s applications. Pratt & Whitney obtained knowledge on impact response of composite components and Defense Research Establishment Val Cartier had an opportunity to analyze an industrial-sized composite component.

The biggest winner in the project is likely Delastek Ltd. and subsequently composite technology in Quebec. Delastek obtained two contracts from Bell to make resin transfer molding composites parts. Other potential contracts with Bombardier may be in the works.
With the increasing use of composites worldwide, Delastek has a good chance to supply composite components to other companies in other countries, citing its success with Bell Helicopter. Composite technology in Quebec and in Canada also benefits, because with the increased capability of this small supplier, the supply chain is more complete.

Another major success of the project is the evidence of the ability to collaborate between the several sectors of the community. This type of collaboration is unprecedented. Even though it may not be possible to be measure its worth in dollars and cents, this collaboration breaks down the preconception that industry and universities cannot work together. This project has proven that collaboration does happen in Quebec. This is a big asset for future projects, and for the synergy between the different sectors.

Several more aircraft composite projects have arisen over the past few years. The success of the bonded composite wing box has paved the way for many other successful projects and many transformed companies to come.