Considerations in the development of flight critical software-based systems using Off-The-Shelf components

Effective management of integrity requirements from the earliest stage of an aviation developmental procurement is essential, but the need is not always properly understood by those involved in the planning process. The paper will consider the key requirements in the definition, design and development of flight-critical systems that are substantially based on Commercial and Military Off-The-Shelf (COTS and MOTS) software-based components. Potential lack of understanding leads to a high risk that potential time, cost and performance factors are not adequately understood. Processes that can be applied to manage these risks will be described. Particular attention is required to components that may have been developed to meet the integrity needs of other application areas, but which may not map well onto the needs of the current intended customer.