At the Institute of Flight Guidance in the Controller Assistance Department, the foundations of a new research field are being laid as part of a doctorate: sonification in air traffic control. Sonification describes the basic procedure for representing the most varied forms of data using different musical parameters such as pitch, volume, timbre, or other musical means. An important question within sonification is how and in what form data can be converted into auditory information so that this transfer and transformation process can create added value in information for the listener.
It is important to note when it comes to the sonic description of movement in space that our auditory system is more extensively equipped than our visual system. For example, our ears enable us to locate sounds from different directions at any time and regardless of which direction we are looking. In doing so, pitches, volumes, and a wide variety of sound qualities are assigned meaning that help us to react appropriately to our environment in a given situation. A roaring lion, a sudden very loud clap of thunder, the soft rattle of a rattlesnake will alert and elevate us in seconds, while the soft rustling of leaves or the bubbling of a river have a calming and decelerating effect.
Newman Scoring Stage, 21th Century Fox in Los Angeles
We can therefore gain important information from our soundscape, which helps us navigate and react directly to dangers. The term ‘soundscape’ became known primarily through the Canadian composer and sound researcher Murray Schafer. Based on the word “landscape”, ‘soundscape’ should be an acoustic perspective, not only as an aesthetic, but also incorporating historical, geographical, and cultural aspects (from Schafer’s book “The Tuning of the World”). Each ‘soundscape’ has its own composition, a sound-ecology, that describes which sounds exist within it and how these sounds relate to one another. For example, we can perceive different sounds in the soundscape of a rural area than we can in a noisy city.
Background music to increase situational awareness during monitoring tasks
These areas are also becoming more and more important within air traffic control. If one considers the current situation of the air traffic controllers, additions to the auditory system wouldn’t make sense, since this is already fully occupied by the communication between the pilot and the controller. However, sonification is intended for a future scenario in which the auditory and visual framework will change. In this future scenario, a data link (CPDLC) between air and ground segments should be used as the primary system and spoken language only as the secondary type of communication. In addition, it was found in various studies that the vigilance (alertness) in monitoring tasks decreases over time. Here the development of a soundscape could be a possible countermeasure.
In this context, the sonification of the air traffic situation could be translated into a quasi-film music representation and soundscape, which should enable the main controller to focus his/her attention on specific problem areas. One possible threatening situation in this context would be two aircraft approaching each other critically close. To find an acoustic equivalent to this, we could, for example, imagine the famous two-tone motif from the film music for “Jaws” by John Williams, which with its dissonant sound, does not bode well. While the bathers are still enjoying their water fun, the shark approaches, note by note, and we as viewers become more aware of the danger in which the pace is slowly but steadily faster and faster. The sound, especially in this case, informs us of what we cannot see, because it is swimming under the water, is presented here musically in full intensity. You could even say that it is only through the threatening music that one becomes aware of the danger. However, situations can also be clarified that are far less threatening, but whose knowledge could still be helpful. For example, the aircraft’s entry into a sector or ascending and descending movements could be displayed in order to give the operator additional acoustic cues about the air traffic situation.
The sonification of the data should serve to increase awareness of the situation during monitoring tasks on the one hand and thus provide possible information on recommendations for action and, on the other hand, point out certain problem areas on the display and thus make work in air traffic control safer and more efficient.