OS and Platform Independent Tool Qualification in Safety Critical Systems 2022-26-0018

It’s a common practice to use different kinds tools to aid in the development and verification of modern safety critical avionics systems. These tools play a key role in avionics engineering and used in all project phases: requirements development, software design, source code development, integration, configuration management, and verification. Tools assist to analyze and improve system safety by automation of some of the activities which if performed manually and are therefore prone to human error. However, incorrect functioning of a tool can have negative impact on the safety and performance of the Safety Critical system. Hence, tools are proposed to be qualified whenever any of the design assurance process(es) described in RTCA/DO-178C or RTCA/DO-254 are eliminated, reduced, or automated using the tool unless the output of the tool is verified manually. Qualification of the tool gives confidence in the tool functionality. Such tools follow typical software development lifecycle for development - Tools Operational Requirement, Tools Design and Development, Tool Qualification and Tool Change Management. RTCA/DO-330 advocates that such qualified tools are to be re-evaluated every time there is a change in tool operational environment. Tool needs to be re-qualified if the applicant is not able to prove the equivalence of the new operating environment/ new version of the computer operating system. This analysis and requalifying effort would at times become very involving and may even overrun the cost of the system under development/ upgrades.

This paper presents technologies and methods, if employed could reduce the cost of requalification and re-deployment of tools significantly and even eliminate the need for requalification due to change in tool operational environment like OS versions on a given platform.