Certification concerns of Integrated Modular Avionics (IMA) systems

The pace of technological advances in the area of integrated modular avionics (IMA) is progressing at a breakneck speed. The FAA is concerned that the complexity of these IMA systems and the interaction between their functions is not well understood, especially under failure conditions. Additionally, given the developing business models used by industry, it is likely that large-scale IMA systems will be developed and integrated by multiple companies. Given the system complexity and aggressive approval schedules, it is extremely difficult to ensure that all aspects of the IMA system have been fully covered during the approval for use on an aircraft. From the FAA perspective, IMA systems are not fundamentally different in nature from more traditional, usually simpler, federated systems. The existing regulations, policy and guidance material that apply to federated systems also apply to IMA systems. What has changed, however, is the complexity of these systems, the possibility of unintended interaction between the individual functions of these systems, and the number of companies that develop components of the IMA system. This requires a high level of care and attention to detail to ensure that the final IMA system is safe and is compliant with, not only the specific existing regulations and guidance material, but also the intent behind the regulations and guidance in the event that they do not adequately cover the proposed IMA design. This paper explores some of the issues and concerns surrounding the approval of large scale integrated modular avionics systems.