# Human Error Types

> Classification of errors and violations in aviation.

- **Subject:** 040 — Human Performance Limitations
- **Section:** 040-03 — Basic Aviation Psychology
- **Topic code:** 040-03-02
- **Last reviewed:** 2026-04-01
- **Author:** Pablo Asensio Martínez
- **HTML version:** https://pilotsyllabus.com/en/human-performance-limitations/basic-aviation-psychology/human-error-and-reliability/

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## Rasmussen's SRK Model
Performance levels determine the type of error:
1.  **Skill-Based (Automated)**: Routine tasks done without thinking (e.g., controlling pitch).
2.  **Rule-Based (Procedural)**: Interpreting a situation and applying a learned rule (e.g., "If fire light ON, then shut down engine").
3.  **Knowledge-Based (Novel)**: New situations requiring analytical thinking (e.g., complex failure with no checklist).

## Error Classification (Reason/Norman)

![Pilot Error Wall](https://upload.wikimedia.org/wikipedia/commons/5/57/Pilot_Error_Wall_%2834031395723%29.jpg)

*   **Slips (Action Error)**: Correct intention, wrong execution. Skill-based.
    *   *Example*: Selecting Flaps instead of Gear.
*   **Lapses (Memory Error)**: Forgetting to do something. Skill-based.
    *   *Example*: Forgetting to report passing an altitude.
*   **Mistakes (Planning Error)**: Wrong intention. The plan is flawed.
    *   **Rule-Based Mistake**: Applying the wrong rule or a bad rule.
    *   **Knowledge-Based Mistake**: Failure in reasoning/understanding the system.

## Violations
Deliberate deviation from rules or procedures.
*   **Routine**: "Corner cutting" accepted by the group.
*   **Situational**: Breaking a rule to get the job done under pressure.
*   **Optimising**: Breaking a rule for personal thrill/ego.

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