# Essential SAR Definitions: INCERFA, ALERFA, DETRESFA, and RCC

> Learn Annex 12 search and rescue definitions, including emergency phase criteria and the coordination role of the Rescue Coordination Centre (RCC).

- **Subject:** 010 — Air Law
- **Section:** 010-11 — Search and Rescue (SAR)
- **Topic code:** 010-11-01
- **Last reviewed:** 2026-03-27
- **Author:** Pablo Asensio Martínez
- **HTML version:** https://pilotsyllabus.com/en/air-law/search-and-rescue-sar/essential-sar-definitions/

---

## Emergency Phases
Annex 12 defines three phases to classify emergency situations:

1.  **Uncertainty Phase (INCERFA):**
    *   Uncertainty exists as to the safety of an aircraft and its occupants.
    *   Example: No communication has been received or it has failed to arrive at the expected time, and no news.
    *   Key word: **Uncertainty**.

2.  **Alert Phase (ALERFA):**
    *   Apprehension exists as to the safety of the aircraft.
    *   Example: Known technical difficulties not involving immediate danger, or following the uncertainty phase with no results.
    *   Key word: **Apprehension**.

3.  **Distress Phase (DETRESFA):**
    *   Reasonable certainty that the aircraft and its occupants are threatened by grave and imminent danger and require immediate assistance.
    *   Example: Known accident, fuel exhaustion, fire on board, forced landing imminent.
    *   Key words: **Grave and imminent danger**.

## Key Definitions
*   **RCC (Rescue Coordination Centre):** A unit responsible for promoting efficient organization of search and rescue services and for coordinating the conduct of search and rescue operations within a search and rescue region.
*   **State of Registry:** The State on whose register the aircraft is entered.

---

Free study notes from pilotsyllabus.com. Not a substitute for training at an approved ATO.