What is a Logic Tree?

A Logic Tree is an organizational tool that you can use to diagram all the possible causes of a failure event. The structure of the Logic Tree is hierarchical so that you can easily reference which event caused what effect. Each cause or effect is represented by a labeled icon, called a node.

There are four types of nodes: Failure Event, Failure Mode, Hypothesis, and Logic Gate. Each node has an associated record, which participates in a predecessor-successor relationship.  For example, each Failure Mode node that appears in the Logic Tree has an associated RCA Failure Mode record that is linked to the root RCA Event record. Additionally, for each Hypothesis node that appears in the Logic Tree, an associated RCA Hypothesis record exists that is linked to the predecessor RCA Failure Mode record and the root RCA Event record. Additionally, when you add a node to the Logic Tree, a link is created between the record for that node and the RCA Analysis record.

The following image illustrates the basic structure of the Logic Tree. For more information on each level of the Logic Tree, click the hyperlinked name on the associated node in the image.