Task order - statement of work (SOW) task title: understanding and evaluating assurance cases 1.0 introduction/background: the current air transportation system is remarkably safe. IT is so safe…

Task order - statement of work (SOW) task title: understanding and evaluating assurance cases 1.0 introduction/background: the current air transportation system is remarkably safe. IT is so safe that traveling by airplane is often thought to be the safest means of travel possible today. A myriad of different reasons contribute to the current high level of safety, including conservative adoption of new technologies, careful introduction of automation to augment human capabilities, and thoughtful reliance on experience for establishing safety-ensuring processes and regulations. However, the complexity and inner-connectivity of the systems, procedures, and processes proposed for the next generation air transportation system (nextgen) cast doubts on whether these reasons will continue to apply, and thus on whether the current approaches to ensuring safety will continue to suffice. Partially in response to these doubts, nasas aviation safety program began the system safety and assurance technologies (ssat) project. Ssat has identified a number of challenge problems, including the assurance of flight-critical systems (afcs) challenge, which has motivated research designed to help ensure the safe deployment of flight critical systems for nextgen and beyond. Working towards the afcs challenge problem, the argument-based safety assurance (absa) sub-element of ssat is targeting three general areas: understanding safety requirements; determining needed evidence; and investigating arguments. This task addresses the use of assurance cases as a means for determining needed evidence and investigating arguments. 2.0 scope & objective(s): the scope of this task order is to investigate the current best practices in using and evaluating assurance cases in the development and approval of safety-critical systems. The objective of this task order is to deliver a document that provides a comprehensive overview of the following: (a) the basic principles, terminology, notations, and existing uses of assurance cases in aviation and other industries; and (b) existing and proposed criteria, methods, and tools for evaluating the clarity, strength, and sufficiency of an assurance case. 3.0 description of the work/tasks to be performed: for this task order, the contractor shall perform the tasks listed below. In completing these tasks, the contractor shall consider the generic term assurance case to fully encompass the specific term safety case. 3.1 study assurance case principles the contractor shall conduct a comprehensive study of the published literature about assurance cases. In conducting the study the contractor shall concentrate on discovering and providing a clear, detailed overview of the basic principles, terminology, and notations used in assurance cases. 3.2 compile list of existing uses of assurance cases the contractor shall compile a comprehensive list of the existing uses of assurance cases on real projects world-wide within the aviation, space, automotive, rail, marine, off-shore oil and gas, military, and medical domains. To the extent possible based on the published materials, for each use discovered, the following items should be documented: name of the project; domain of the project; organizations involved (including regulatory authorities, if any); standards followed in producing the assurance case (if any); notations used; assessment of whether the project was a success or failure and why; availability of the actual assurance case(s) to the public; and source(s) of information (including web pages). 3.3 investigate existing approaches to evaluating assurance cases the contractor shall investigate the criteria, methods, and tools currently used or proposed to be used to evaluate whether an assurance case provides sufficient confidence that a particular system or service is fit for its intended use. At a minimum, this investigation SH