Description

Recordings made by various systems involved in ATS operations provide a source of objective data. They are created and stored primarily in order to assist during accident and incident investigations but can be used for other purposes as well, e.g.:

• Search and rescue operations
• Air traffic controller training
• System monitoring and evaluation

ATS recording systems collect and store data from a variety of sources which can be divided into two major groups:

• Visual data, such as:
  • Surveillance data, i.e. data received from PSR, SSR, MLAT and ADS-B/ADS-C. Note that while this is a valid way to reconstruct a situation, it does not always provide a complete picture of what the participating controllers have observed during the event.
  • Screen recordings of situation displays. These provide an exact picture of what the controller has seen and done during the occurrence. This includes the screen layout, settings such as filters as well as all controller interactions with the system (e.g. use of various tools, reaction to alerts, etc.).
• Communication recording, including:
  • Recording messages exchanged on the operational frequencies
  • Recording datalink messages, such as AFTN, CPDLC and OLDI
  • Recording phone calls from operational positions (i.e. controller working positions, the shift supervisor phone, etc.)
  • Ambient recording, which allows to reconstruct the communications between the executive and planner controllers on a particular sector as well as communication with other people in the vicinity of that sector (e.g. the supervisor). The use of such recordings is normally limited to accident and incident investigations.

Other data relevant to ATS operations can also be recorded (e.g. traffic preditions used for [[sector management]]) in order to evaluate system and procedure performance and develop improvements.

The recordings are stored for a period of time defined (normally as a minimum) in relevant regulations.

Further Reading

• ICAO Annex 10, Vol. 2
• ICAO Annex 11
• Regulation 2020/469
• FAA JO 7210.3 - Facility Operation and Administration, Part 1, Chapter 3, Section 4: Recorders