Fort Hill Group developed a comprehensive process for assessing the risks and causal factors associated with maintenance operations.

Airway Transportation Systems Specialists play a critical role in maintaining the systems and infrastructure that support operations in the National Airspace System (NAS). Any system outage or degraded mode of operation can have a considerable impact on an air traffic controller’s ability to provide services to pilots. In order to assess the impact of technical occurrences where the ability to provide air traffic services has been affected, the Federal Aviation Administration (FAA) has developed and deployed the Service Integrity Risk Analysis Process (SI-RAP). SI-RAP is a post-event analysis tool designed to assess the risk associated with an occurrence based on severity and repeatability of the event. The FAA utilized the experience and expertise of Fort Hill Group to develop the process for assessing the repeatability of a technical occurrence. To support this effort, Fort Hill Group developed a taxonomy of factors impacting repeatability, a standardized process for applying the taxonomy, and a comprehensive three-day training course.

SI-RAP Event Repeatability Taxonomy 

The SI-RAP taxonomy was developed through a review of existing taxonomies from other domains, maintenance expert opinion elicitation sessions, domain customization, and test case applications. The structure of the SI-RAP taxonomy was developed to be consistent with existing FAA and international risk analysis processes, while the details of the taxonomy factors were tailored to the technical operations domain. Additionally, the SI-RAP taxonomy incorporates the human factors areas from the Air Traffic Analysis and Classification System (AirTracs) taxonomy. The SI-RAP taxonomy is composed of four tiers: Personnel Factors, Contextual Factors, Equipment Factors, and Systemic Factors. Each tier is composed of categories that group related taxonomy factors.

SI-RAP Walkthrough Application

In conjunction with the development of the repeatability assessment process, Fort Hill Group developed an interactive, web-based application to guide the risk assessment panel members through the repeatability assessment process. The application allowed each panel member to have direct access to repeatability factor definitions and examples. It further provided a structured walkthrough of the repeatability factors to ensure panel members thoroughly and consistently considered the available factors for each safety event that they analyzed.

SI-RAP Training Program

Fort Hill Group developed and deployed a comprehensive training program for all members of the SI-RAP team to ensure that each risk assessor was equipped to assess each safety event. The three-day training program introduced the SI-RAP team to human factors topics and all elements of the SI-RAP taxonomy. As part of the training, panel members practiced applying each level of the SI-RAP taxonomy in addition to application activities via multiple case studies where panel members applied the full taxonomy to assess repeatability. At the conclusion of the training, SI-RAP panel members were presented with an introduction to the benefits and methods for conducting aggregated data assessment to identify repeatability factor trends across large data sets.

For more information on the SI-RAP taxonomy, download Incorporating Human Factors into the Service Integrity Risk Analysis Process: A SI-RAP Taxonomy and Training Program


For more information on this project, please contact us at [email protected]