Matthias Wies

Reducing controller workload with automatic speech recognition

Air traffic controllers normally manage all aircraft information with flight strips. These strips contain static information about each flight such as call sign or weight category. Additionally, all clearances regarding altitude, speed, and direction are noted by the controller. Historically paper flight strips were in operation, but modern controller working positions use electronic flight strips or electronic aircraft labels. However, independent from the type, considerable controller effort is needed to manually maintain strip information consistent with commands given to the aircraft. Automatic Speech Recognition (ASR) is a solution which requires no additional work from the controller to maintain radar label information. The Assistant Based Speech Recognizer developed by DLR and Saarland University enables command error rates below 2%. Validation trials with controllers from Germany and Austria showed that workload reduction by a factor of three for label maintenance is possible.

Monitoring principles in aviation and the importance of operator redundancy

The aim of this paper is to discuss developments in aviation with respect to their affect on redundancy and dependability of the complex human-automation system. With the improvement of technical systems and increasing automation in aviation, the attempts to reduce the number of human operators in the flight guidance system is still one goal of current research. Single pilot cockpit or single controller working positions are the key words for pinpointing this issue. For technical systems, the developments aim at the integration of a higher level of redundancy to improve the dependability. A contrary trend is determinable for the human operator by transitioning to single operator systems. To be able to evaluate this process, this paper analyses three different monitoring principles that form the basis for redundancy and thus dependability. These monitoring principles are (a) the automation-automation, (b) the human-automation, and (c) the human-human. Research that focuses on single operator systems consequently eliminates the human-human monitoring principle. The authors argue that the consequences of this elimination are currently not understood sufficiently and may have a great impact on the dependability of the overall system, as some highly valuable aspects of the human-human monitoring principle would be irreplaceably lost with the transition to single operator systems.

Does Cognitive Lockup Depend on the Situation, on the Person, or on an Interaction of Both?

This paper focuses on investigating (a) whether cognitive lockup can be provoked in an experimental setup in a realistic, generic cockpit simulator and (b) whether the occurrence of cognitive lockup further depends on the pilot or on an interaction between the aviation situation and the pilot. To investigate these research questions, an experiment was conducted during which pilots aviated two scenarios. Both scenarios reflect an approach situation in which the second autopilot failed as a first event and the runway was changed as a second event. The main difference of the scenarios is the timing of the autopilot failure and the runway change: In the experimental condition, the events occurred later in time, which reduced the time frame available for the briefing. While aviating, the aircraft’s maximum deviation from the specified route was recorded. Statistical analyses showed that pilots were more drawn to cognitive lockup in the situation with more time-pressure resulting in a performance degradation in the aviation task. Aviation performance was further predicted by a significant interaction between the person and the situation, which shows a need to also consider person-related variables when explaining the occurrence of cognitive lockup.

Investigating attentional tunneling through a flexible experimentation environment and eye tracking

Although attentional tunneling as a phenomenon is at least known since the late 1970ies, it is still an area of high research interest, since it bears connections to current and future applications in head-up and head-down displays. For example, it is still not fully answered to what degree highly dynamic scenarios influence the pilots ability to keep up with routine tasks, and vice versa, when and whether dynamic scene changes stay unnoticed under high workload. In order to further investigate attentional tunneling a generic experimentation environment was set up. The core of the environment is DLRs flexible sensor simulation suite (F3S). This simulation software can be installed on specialized simulation platforms, for example a Vision Station, as well as on standard workstations and can be tuned to a simple view simulation with different levels of realism. It allows for a full and dynamic control of experimental scenarios, for example possible changes in the environment. For larger scenarios several platforms can be coupled to enable the investigation of team situations. As one of its key features the set-up includes a full eye-tracking solution that is further capable of recording dynamic areas of interest. Within a first experiment with a student sample F3S was used as a simple view simulation combined with synthetic approach scenarios. Subjects were asked to detect changes whilst flying highway-in-the-sky approaches with a head-up display. At the same time eye gaze positions where tracked. This novel approach to the investigation of attentional tunneling can prove that an environmental change, even though visually perceived, is not necessarily cognitively processed at the same time.