Description

The Search and Rescue (SAR) function is a state obligation imposed by the Convention on International Civil Aviation (Chicago, 7 December 1944) which is generally referred to as the Chicago Convention. Annex 12 to the ICAO Chicago Convention defines three emergency phases which are referred to as the Uncertainty Phase, the Alert Phase and the Distress Phase. These phases are defined as follows:

• Uncertainty phase (code word INCERFA): a situation wherein uncertainty exists as to the safety of an aircraft and its occupants
• Alert phase (code word ALERFA): a situation wherein apprehension exists as to the safety of an aircraft and its occupants
• Distress phase (code word DETRESFA): a situation wherein there is a reasonable certainty that an aircraft and its occupants are threatened by grave and imminent danger and require immediate assistance

Phase Initiation

Each State is responsible for developing and promulgating clear criteria for the declaration of each emergency phase. Air Traffic Services (ATS) or the responsible Rescue Coordination Centre (RCC), as appropriate, will make the Emergency Phase declaration within the timeframe specified for the trigger event. As an example, loss of radio contact with an aircraft under ATS control could result in declaration of the Uncertainty Phase within 10 minutes, the Alert Phase within 20 minutes and the Distress Phase within 30 minutes of the event whereas loss of radio contact with an aircraft not under ATS control might not trigger the Uncertainty Phase declaration until 30 minutes had lapsed with Phase upgrade occurring at 30 minute intervals.

Recommended Actions

Upon the declaration of an Uncertainty Phase by the RCC or by an ATS Unit, the RCC should:

• Verify the details of the flight as provided by the alerting unit. In particular, details of the aircraft involved should be gathered and confirmed to the extent possible. These details should include but are not limited to:
  • call sign or registration
  • aircraft description including type of aircraft, colours and marking
  • number of passengers on board (POB) and, if available, names
  • category of operation (visual flight rules (VFR) or instrument flight rules (IFR))
  • pilot rating and experience
  • place of departure, destination and planned route
  • actual time of departure and estimated time of arrival
  • fuel endurance and fuel expiry time
  • time of last communication
  • last known position
  • any other relevant information.
• Log all incoming information and progress reports, details of action taken and subsequent developments
• Maintain close liaison with relevant ATS Units for updates or changes in status
• Continue the communication search, either directly or through other ground or airborne assets
• Plot the flight path of the aircraft involved to the point that contact was lost, making use of all relevant information
• Determine the most probable location or most likely continuation of the route of the aircraft involved

If the communication search and/or other information acquired indicates that the aircraft is not in distress, the RCC will cancel the SAR phase and immediately inform all concerned parties. In cases where the aircraft has not been located after application of the above procedures, the need to upgrade the emergency phase will be considered.

Upon the declaration of an Alert Phase, the RCC should:

• Complete or initiate all relevant actions as detailed for the Uncertainty Phase
• Ensure that a SAR Mission Co-ordinator (SMC) has been appointed
• Alert appropriate SAR facilities
• Review all information received;
• Continue efforts to obtain information about the distressed aircraft from all available sources
• Carefully re-evaluate all known details of the flight to confirm estimated position or most likely route of flight performance under adverse conditions
• Estimate and plot the probable position of the aircraft and its maximum range from its last known position
• Maintain close liaison with relevant ATS Units
• If appropriate, initiate search planning
• Whenever practicable, communicate all information received and action taken to the operator

If it is determined that the aircraft is not in distress, the RCC will cancel the SAR phase and immediately inform all parties concerned. However, if the aircraft has not been located after extensive application of the above procedures, the SMC should consider the need to review/upgrade the emergency phase.

Upon the declaration of a Distress Phase the RCC should:

• Complete all relevant actions as detailed for Uncertainty and Alert Phases
• Further develop a plan for the conduct of the required SAR operation and communicate that plan to the appropriate authorities/agencies inclusive of the affected Area Control Centres (ACC) and all RCCs whose areas of responsibilities lie within the maximum range of the aircraft based on its last known position
• Estimate the most likely position of the distressed aircraft, evaluate the degree of uncertainty of this position and determine the extent of the area to be searched
• Select and notify designated SAR Units for deployment
• Request aircraft, vessels, radio stations, and other facilities not specifically designated as SAR Units, that are appropriate and able to assist, to:
  • maintain a listening watch for transmissions from the aircraft in distress
  • assist the aircraft in distress as far as practicable
  • prepare for deployment on SAR tasks
  • inform the RCC of any developments
• Notify:
  • The State of Registry of the aircraft
  • The State of the Operator of the aircraft
  • The appropriate accident investigation authorities
  • The operator and keep them informed of developments

Related Articles

• Emergency or Abnormal Situation
• Classification of Airspace
• Emergency Locator Transmitter (ELT)
• Underwater Locator Beacon (ULB)
• Emergency Communications

Further Reading

ICAO

• Annex 12 to the Convention on International Civil Aviation