Sleepless Skies: Are Air Traffic Controllers Facing a Hidden Health Crisis?
"A Brazilian study reveals the alarming rates of excessive sleepiness among air traffic controllers, raising concerns about safety and well-being."
Air traffic controllers (ATCos) shoulder immense responsibility, ensuring the safe and efficient flow of air travel. Unlike typical 9-to-5 jobs, their work involves irregular shifts, demanding constant vigilance and quick decision-making at all hours. But what impact do these demanding schedules have on their health, particularly their sleep?
A recent study conducted in Brazil sheds light on a concerning issue: excessive sleepiness among air traffic controllers. This research, published in Dement Neuropsychol, investigated the prevalence of excessive sleepiness (ES) in Brazilian ATCos and its potential implications.
The study evaluated 45 flight protection professionals, including 30 ATCos divided into groups based on their years of experience (over ten years and less than ten years) and 15 aeronautical information services operators (AIS) serving as a control group. Researchers used the Epworth Sleepiness Scale and the Maintenance of Wakefulness Test to assess subjective and objective sleepiness levels.
Fatigue and Rotating Schedules
Research has examined air traffic controller fatigue through workforce characteristics, work requirements, and scheduling practices. One report found that controllers averaged only 2.3 hours of sleep before a midnight shift, defined as work occurring mainly between 10 p.m. and 8 a.m. Another study found that controllers on a 2-2-1 rotation reported better sleep on days off than those on a five-day rotation.
Rostering and Fatigue Management
Fatigue in air traffic management is treated as a safety concern, with organizations such as ICAO and EASA advocating fatigue risk management systems. EU Regulation 2017/373, implemented in January 2020, established requirements for air navigation service providers concerning controller fatigue, stress, and rostering. Recent field studies have also examined how irregular and preference-based shift systems affect subjective and objective fatigue, sleep quality, vigilance, mental workload, and boredom.
From Sleep Science to Controller Research
Historical sleep research identified several foundational milestones, including the discovery of brain activity during sleep, the effects of artificial lighting on society, and the phenomenon of sleep inertia. An earlier document on air traffic controllers recorded disagreement between controllers and management about whether the 2-2-1 rotation produced adverse physiological or psychological effects. This history shows how understanding sleep biology and workplace scheduling developed alongside debate about operational impacts.
What the Study Revealed: Alarming Rates of Sleepiness
The findings of the Brazilian study were quite striking. ATCos, regardless of their years of experience, reported significantly higher levels of subjective sleepiness compared to the control group (AIS operators). Specifically, ATCos with more than ten years of experience showed a median sleepiness score of 12 (out of 24) on the Epworth Sleepiness Scale, while those with less than ten years scored 10. In contrast, the control groups scored much lower.
- Epworth Sleepiness Scale (ESS): A score above 9 indicates excessive sleepiness. ATCos scored significantly higher than the control group.
- Maintenance of Wakefulness Test (MWT): Measures how long a person can stay awake in a quiet environment. Shorter sleep latency indicates greater sleepiness.
- Key Finding: ATCos exhibited both subjective feelings of sleepiness and objective measures confirming their difficulty in staying awake.
A Practical Fatigue Toolkit
Two recent case studies investigated fatigue among air traffic controllers using an agile, user-friendly toolkit. The toolkit measured sleep duration and quality, mental workload, boredom, and vigilance. This approach illustrates a broader effort to combine subjective reports with operationally relevant measures when studying controller fatigue.
The Costs of Rotating Shifts
Rotating shiftwork is common among air traffic controllers and has been associated with sleep deprivation, biological adaptations, and changes in daily life. The available description of one study indicates that it assessed quality of life, sleep, and health rather than treating fatigue as only a scheduling issue. Other accounts emphasize that irregular hours can misalign work with circadian timing while requiring sustained, high-stakes performance.
Fatigue Across Shift-Based Work
Air traffic controllers and many air traffic engineers work shifts, making fatigue risk a shared feature of these roles. The central comparison is not simply whether workers are tired, but how shiftwork affects the human performance capabilities that air traffic control requires. These include planning, situational awareness, and sound decision-making, which must remain consistently strong in safety-critical operations.
Addressing the Sleepless Skies: What Can Be Done?
The Brazilian study serves as a wake-up call, prompting the need for further research and proactive interventions. Understanding the specific factors contributing to sleep deprivation in air traffic controllers is crucial for developing effective strategies to combat this issue. Some potential solutions include optimizing work schedules, promoting sleep hygiene education, and providing access to sleep disorder treatments.
A Formal Warning on Fatigue
In December 2023, independent experts evaluated current scientific knowledge about human sleep needs and fatigue as it applied to the FAA air traffic controller workforce, work requirements, and scheduling practices. Their final report, Assessing Fatigue in the FAA Air Traffic Operations, raised serious concerns about controller schedules and fatigue. The assessment places scheduling at the center of the discussion rather than treating fatigue as an individual problem alone.
What Comes Next
Future work will likely need to examine how scheduling, sleep opportunity, and operational demands interact over time. Progress should be measured through both worker health indicators and performance-related outcomes. Because the available material does not establish a single solution, any next steps should remain evidence-led and attentive to uncertainty.
A System-Level Problem
Controller fatigue can be understood as a systemic challenge shaped by work schedules, circadian timing, and the demands of safety-critical performance. Focusing only on individual sleep habits risks overlooking organizational and operational conditions. A broader approach should consider how staffing and rostering practices influence the conditions in which controllers work.
Beyond the Schedule
Sleep disruption affects more than a worker's alertness during a single shift; it can also influence health, quality of life, and daily routines. For air traffic controllers, these personal effects occur alongside the responsibility to maintain reliable performance. Recognizing that human dimension is essential to evaluating fatigue policies without reducing workers to operational variables.