3.4  Use of Results  3.4.1  Preliminary Requirements  3.4.2  Safety Risk Management Documents  3.4.3  Safety Requirements Verification Table  4  OSA Inputs  4.1  FHA 4.1.1  What is an FHA?  4.1.2  Purpose of an FHA 4.1.3  FHA Overview  The results of the OSA are used as input to various documents. Controls and safety requirements identified through the OSA process must be included in the  preliminary Program Requirements Document (pPRD). The pPRD must include a requirement  for DALs in accordance with Appendix J. Other preliminary requirements must be separately  documented, such as new/modified Air Traffic Control (ATC) procedures, changes to the Codes  of Federal Regulation, and training.  The output of the OSA is used as input for Safety Risk Management (SRM) documents that the  PO must develop as the solution is further developed (e.g., Comparative Safety Assessment,  Preliminary Hazard Analysis, or System Hazard Analysis / Sub-System Hazard Analysis).  The Safety Requirements Verification Table contains all of the safety requirements identified,  starting with the origin of the requirement (including those identified in the OSA).  An FHA is not a required AMS safety analysis; but if one is conducted, it can be useful input for  the OSA (particularly when complex systems are being developed).  The PO may conduct an FHA to identify credible operational safety effects through the analysis  of system or sub-system functions and failure conditions. The FHA is a methodical approach  that identifies and classifies the system functions and safety hazards associated with functional  failure or malfunction. It identifies the relationships between functions and hazards, thereby  identifying the safety-significant functions of the system as well as the hazards associated with  that functionality. This identification provides a foundation for the safety program to scope  additional safety analyses.  The purpose of an FHA is to identify every expected function of a system and consider the  hazards that may result when each function fails in every possible way. It does not determine  causes of the hazards but rather focuses on the consequences and corresponding severities. As a predictive technique, the FHA attempts to explore the effects of functional failures of parts  of a system. A guiding principle of the FHA is that if safety requirements are added at the  functional level early in the system development process, the design of the system will be more  stable from a safety perspective, and the cost of implementing safety mitigations will be  reduced.  The FHA is an engineering-oriented analysis. To conduct an FHA, the PO must convene a  technical or engineering-oriented workgroup before any SRM panel is held to review the  Functional Analysis (FA), pPRD (if available), Enterprise Architecture (EA) artifacts, and other  inputs. To assist the safety program by defining functions and identifying likely functional  hazards, the FHA facilitates discussion of mitigations and solutions. The FHA assists any  stakeholders participating in subsequent SRM panels (e.g., to conduct OSAs) who may not  C_SRMGSA_202003  Originally published March 2020  Uncontrolled copy when downloaded  C-4