Mission Ready Software

Our software fault tree analysis training covers the most common root causes of software failures and how to brainstorm them when conducting a system fault tree analysis. This class is intended for software engineers, system engineers, safety engineers and RAM engineers.

A common mistake in software safety is analyzing software faults in isolation, as a “black box” that either works or fails. For a  Fault Tree Analysis or software (FTA) to be effective, software must be integrated into the system-level fault tree from a functional perspective.

Ineffective vs. Effective FTA Approaches

An ineffective approach to FTA is to simply add a generic event like, “Software failed.” This provides no useful information for hazard mitigation.

A practical and effective approach is to analyze how the software could fail in a specific, functional way. For example, a more useful fault tree event would be, “The software allowed an inadvertent state change.” This pinpoints a specific failure mode that can then be traced to its root causes within the software’s design or code.

FTA Complements safety assessements

FTA is a top-down analysis that starts with a high-level hazard and works backward to find the root causes. This makes it a powerful tool for identifying unknown hazards in complex systems, especially when dealing with new technologies or difficult-to-reproduce field issues.

FTA is often used alongside Failure Modes and Effects Analysis (FMEA), which is a bottom-up analysis. FMEA starts with potential component failures and traces their effects on the system. Together, FTA and FMEA provide a comprehensive view of system safety from both a top-down and bottom-up perspective.