A tailored Top-Down Functional Analysis (TDFA) for AEGIS Ballistic Missile Defense (ABMD)

Abstract

A TDFA is often cited as a major analysis needed when developing a new system. However, designing new components for pre-existing U.S. Navy systems presents a unique challenge. This paper describes the application of a modified TDFA to an existing system with new capabilities and functionality. New technologies introduced in the ABMD Baseline 5.1 include the Standard Missile (SM)-3 Block (Blk) IIA, which will provide superior speed, range, and discrimination capabilities relative to earlier SM-3 missile variants. This will lead to better performance against existing threats as well as entirely new mission capabilities. However, the areas impacted by this technology comprise a small subset of the overall AEGIS Weapon System functionality. As a result, a hybrid methodology for the TDFA was developed collaboratively by industry and government teams to ensure that outputs fit into the systems engineering process and ultimately the display design process. The hybrid TDFA methodology was developed as a means to help identify the information considered necessary to support warfighter decision making during mission planning and the ability to achieve the mission goal of successful ballistic missile threat kills during mission execution. An example is provided that shows how the hybrid methodology has impacted the development of prototype displays to date. It is concluded that this hybrid TDFA approach has demonstrated utility in the development of lower level requirements for these displays and is recommended for use when the system is already well-known and only a portion of the system in design will be considered new or changed functionality.

Towards a Graphical Grammar for Task Analysis Visualization

“…GDTA: Goal Directed Task Analysis (Humphrey, & Adams, 2011) 4. TDFA: Top-Down Functional Analysis (Colombo, Chavez, & Driscoll, 2012) 5. CIT: Critical Incident Technique (Flanagan, 1954; Kirwan & Ainsworth, 1992) 6.…”