Architecture description languages such as AADL allow systems engineers to specify the structure of system architectures and perform several analyses over them, including schedulability, resource analysis, and information flow. In addition, they permit system-level requirements to be specified and analyzed early in the development process of airborne and ground-based systems. These tools can also be used to perform safety analysis based on the system architecture and initial functional decomposition. Using AADL-based system architecture modeling and analysis tools as an exemplar, we extend existing analysis methods to support system safety objectives of ARP4754A and ARP4761. This includes extensions to existing modeling languages to better describe failure conditions, interactions, and mitigations, and improvements to compositional reasoning approaches focused on the specific needs of system safety analysis. We develop example systems based on the Wheel Braking System in SAE AIR6110 to evaluate the effectiveness and practicality of our approach.