SAE ARP4754A and ARP4761 provide guidelines and analysis methods for performing functional hazard and system safety assessments to verify and certify civil airborne systems and equipment. In these SAE documents, the main focus for fault trees is to determine the probability of failure per flight or failure per flight hour. Therefore, the top event in the tree usually indicates the occurrence of an undesired event within a flight.

When you set up the FTA module for the construction of SAE trees, you must specify an exposure time, also known as an ‘at risk’ time, for each basic event. Additionally, you must indicate if the item might fail latent and supply monitor information if dedicated hardware circuitry, software code, or a method is used to watch the status of the item and detect latent failures.

To make the creation and setup of a Project with SAE trees simple, you should use the New Project Wizard to create the Project from the supplied FTA Civil Aerospace Template. Using this template as the basis for an SAE Project ensures that SAE ARP4754A and ARP4761 is selected as the default FTA calculation type in the Project properties. It also ensures that FTA tables in the Project’s System files contain SAE-specific fields.

For additional information specific to constructing and calculating SAE trees, see: