Until today thin walled composite primary aerospace structures were joined by using a large number of fasteners. Bolt free joining would considerably contribute to the weight and cost reduction of aerospace structures.
The main challenge of the BOPACS project is to reduce the weight and costs of primary aerospace structures by developing bolt free adhesive bonded joints that comply with the airworthiness requirements.
Within BOPACS target applications will be selected that are commonly used in today's primary aerospace structures and where adhesive bonding might advantageously replace conventional riveting / fastening. Based on these target applications, bolt free adhesive bonded joining methods will be developed which comply with the EASA airworthiness requirements. Contrary to projects focusing on the development of non-destructive techniques for the inspection of weak bonds, BOPACS proposes a rigorous road map to certification by developing Means of Comply based on:
- Thorough research, beyond the state of the art, into the crack growth / Disbond extension mechanisms in adhesively bonded joints
- Design, analysis, testing and assessment of different categories of crack stopping design features, i.e. features that are capable of preventing cracks or Disbonds from growing above a predefined acceptable size, with a joint still capable of carrying the limit load
The project results and certification issues are reviewed on a regular base by EASA representatives through the Airbus certification department.