What is the difference between immediate cause and underlying cause in accident analysis?

• A. Immediate cause is the direct trigger of the mishap; underlying causes are deeper systemic factors that created the conditions.
• B. They are unrelated concepts.
• C. Immediate cause is a design flaw; underlying cause is maintenance error.
• D. Immediate cause is the weather; underlying cause is pilot error.

Answer: (A)

Immediate causes are the direct trigger of a mishap—the specific event or action that directly leads to the accident. Underlying causes are the deeper, systemic factors that created the conditions for that trigger to occur, such as shortcomings in training, maintenance, procedures, supervision, or organizational culture. Recognizing both helps you see not only what happened at the moment, but also the root weaknesses in the system that allowed it to happen, so corrective actions can prevent recurrence. In practice, you identify the immediate trigger and then trace back to the underlying factors that set the stage for it.