Qualitative Insights on the Stressors and Stress Mitigation and Recovery Strategies in Air Traffic Control Training

FAA Office of Aerospace Medicine 
Civil Aerospace Medical Institute

Report No: DOT/FAA/AM-26/17

Title and Subtitle: Qualitative Insights on the Stressors and Stress Mitigation and Recovery Strategies in Air Traffic Control Training

Report Date: April 2026

Authors: Day, E. A., Winsett, P., Beckel, J., Ho, T., Fischer, S. J., Rice, J., Mahmoud, D., Lue, J. C., Barrett, J., Wenger, M. J., Shi, D

Abstract: 
This report starts with an overview of a new, multi-phase interdisciplinary program of research. This program of research involves both lab and field studies to advance theory and practice on distress mitigation in high-performance, safety-critical occupations like air traffic control (ATC). This report summarizes a foundational qualitative study designed to extend prior stress research in ATC training via a qualitative approach involving semi-structured interviews with six subject matter experts (SMEs) with ATC instruction-related experience. We identify key stressors and stress mitigation and recovery strategies relevant to Federal Aviation Administration (FAA) Academy, college training initiative(CTI) students, and developmental controllers in field training. We framed our approach with a discrepancy-reduction, action theory perspective of stress and work performance. Findings provide foundational insight for interventions that address how trainees manage stress and how training environments can be structured to support their success, highlighting the importance of skill development through repeated practice opportunities with supportive instructors. Findings are discussed in terms of how they (1) extend and complement recent reports focused on reducing the physiological and emotional strain experienced in training and (2) point to the interpersonal dynamics between instructors and learners as vital to ensuring students and developmentals become active learners who are not afraid to take action and learn from mistakes.

Key Words: air traffic control, training, stressors, stress mitigation, error recovery.

No. of Pages: 33

Benchmarking Fatigue in United States Helicopter Air Ambulance Pilots

FAA Office of Aerospace Medicine 
Civil Aerospace Medical Institute

Report No: DOT/FAA/AM-26/15

Title and Subtitle: Benchmarking Fatigue in United States Helicopter Air Ambulance Pilots

Report Date: 2/6/2026

Authors: Hannah M. Baumgartner, Justin Durham, Teena Sanders, Sarah E. Westrick,Cassie J. Hilditch

Abstract: 
Helicopter air ambulance (HAA) pilots are exposed to fatigue risk due to on-call and shiftwork operations required for24-hour emergency service. The current field study aimed to provide a benchmark for fatigue in US HAA operations to inform future fatigue management strategies. US HAA pilots working 7-days-on, 7-days-off schedules were invited to participate in a field study. Data collection included 3 days Pre-hitch, a 7-day Duty Period (hitch), and 3 days Post-hitch(recovery) and involved reaction time tests, subjective sleepiness and fatigue ratings, workload ratings, and actigraphy to estimate sleep metrics. Pilots (N = 120, from 21 US HAA companies) working either daytime, nighttime, or mixed(e.g., 3 days followed by 4 nights) schedules completed an initial survey followed by 13 days of data collection during normal operations. The current study found that: (i) half of the HAA pilots surveyed have poor quality sleep; (ii)cumulative fatigue builds across a 7-day hitch, affecting performance on all schedule types; (iii) pilot subjective fatigue and sleepiness ratings remained consistent, even when objective measures of performance worsened; (iv) pilots obtain less sleep during a hitch than on days off on all schedule types, despite taking extra naps during night duties; (v)fatigue accumulates faster across a duty period for night and mixed schedules compared to day schedules; (vi) fatigue accumulated across a hitch persists into recovery days; (vii) circadian disruptions associated with flight requests and subsequent trips operated during periods of low circadian alertness negatively impact performance; and (viii) pilots experience sleep inertia effects (reduced alertness) when woken up by a flight request. Altogether, these results offer the most comprehensive assessment of US HAA pilot fatigue since the introduction of updated HAA regulations in 2014and offer a number of potential fatigue mitigation opportunities for the industry.

Key Words: fatigue, helicopter air ambulance, HEMS, sleep

No. of Pages: 65
 

Prioritizing Safety-Critical Information in the National Airspace System: A Four-Phased Human Factors Methodology and Its Future Applications

FAA Office of Aerospace Medicine
Civil Aerospace Medical Institute

Report No: DOT/FAA/AM- 26/07

Title and Subtitle: A Targeted Review of Safety Culture Interventions: Tools and Insights for Aviation Regulators

Report Date: March 2026

Authors: C. S. Sanders

Abstract:
This report describes a methodology for sorting and prioritizing safety-critical aeronautical information, developed in response to a National Transportation Safety Board recommendation. The methodology integrates human factors and risk assessment principles to identify systemic vulnerabilities in information management and to align information delivery with operational, cognitive, and contextual demands. The approach applies the bow-tie risk model to represent human factors constructs as threats that weaken preventive barriers. Information characteristics, including volume, relevance, timeliness, and modality, are modeled as drivers of these threats and are explicitly linked to preventive and mitigative controls. The resulting framework supports operationally realistic filtering, sequencing, and delivery strategies. The methodology is executed in phased activities, including expert knowledge elicitation, scenario-based simulation, and development and validation of a decision support tool. Certified professional controllers and other operational roles complete realistic scenarios varying in complexity, traffic load, and environmental conditions. Data include event-linked performance metrics, post-scenario interviews, and standardized measures of workload, Situation Awareness, and trust. Integrated quantitative and qualitative analyses identify patterns in information use, decision making, and operational outcomes. Outputs include evidence-based recommendations for training, interface design, and policy and procedural improvements to reduce operational risk and support resilient operations. The scope is limited to the contiguous United States, with future research recommended for non-contiguous regions.

Key Words: Safety-critical Information, Contextual Demands, Standardized Measures

No. of Pages: 122

Federal Aviation Administration Aircraft Evaluation Division Operations andHuman Factors Evaluation Aid for Synthetic Vision Guidance Systems

FAA Office of Aerospace Medicine
Civil Aerospace Medical Institute

Report No: DOT/FAA/AM-26/09

Title and Subtitle: 
Federal Aviation Administration Aircraft Evaluation Division Operations and Human Factors Evaluation Aid for Synthetic Vision Guidance Systems

Report Date: February 2026

Authors: Kelene A. Fercho and Bryan L. Watson

Abstract: 
This evaluation aid is designed to assist the Federal Aviation Administration (FAA) Aircraft Evaluation Division (AED)personnel in evaluating the human factors aspects of a synthetic vision guidance system (SVGS) and aircraft combination for operational suitability evaluations and operational evaluations. This aid supports the evaluation of new or modified SVGSs on different types of aircraft and with different display implementations. This aid may facilitate early identification of human factors issues that may influence safety or human performance during tasks, procedures, maneuvers, or operations conducted with an SVGS. Additionally, the use of this aid may support AED personnel in reviewing the applicant’s Evaluation Plan and may facilitate the development of an AED Summary Report, Flight Standardization Board Report, Letter of Authorization, Letter of Authorization Report, Operational Suitability Letter, Operational Suitability Report, or Type Inspection Authorization. This aid takes the form of a workbook, and each chapter can be used alone or in conjunction with other chapters. This aid comprises five chapters and one appendix—“Introduction”; “Operational Suitability Evaluation”; “Operational Evaluation: Training Recommendations”; “Operational Evaluation: Checking Recommendations”; “Operational Evaluation: Currency Recommendations”; and “Appendix: Key References for the Federal Aviation Administration Aircraft Evaluation Division Operations and Human Factors Evaluation Aid for Synthetic Vision Guidance Systems.” The “Operational Evaluation: Training Recommendations” and “Operational Evaluation: Checking Recommendations” chapters also include decision trees to support the determination of training difference levels or checking difference levels for a modified SVGS and aircraft combination, respectively. Links to key FAA regulatory, policy, and guidance materials are provided within each chapter and in the appendix.

Key Words: 
Advanced vision systems, aircraft evaluation division, checking, currency, evaluation aid, human factors, operational evaluation, operational suitability evaluation, synthetic vision guidance system, synthetic vision system, SVS, SVGS, training

No. of Pages: 224

A Targeted Review of Safety Culture Interventions: Tools and Insights for Aviation Regulators

FAA Office of Aerospace Medicine
Civil Aerospace Medical Institute

Report No: DOT/FAA/AM- 26/05

Title and Subtitle: A Targeted Review of Safety Culture Interventions: Tools and Insights for Aviation Regulators

Report Date: February 2026

Authors: Julia Beckel, Casey Yetter, and Kylie K. Worthington

Abstract:
Promoting a positive safety culture is essential to managing safety risks in aviation organizations. However, many safety culture change efforts fail due to a lack of evidence-based strategies. This literature review synthesizes research from safety, psychological, and organizational sciences to identify effective approaches for safety culture improvement. Findings are organized among the 10 dimensions of the Harmonized Safety Culture Model developed by the International Atomic Energy Agency (2020). The Federal Aviation Administration has adopted the IAEA’s model for assessing safety culture within the agency and for overseeing the safety culture of its regulated entities. Following a review of the literature, we offer practical recommendations for implementing safety culture interventions within the aviation industry, as well as limitations and implications for future research.

Key Words: Safety Culture, Safety Climate, Safety Culture Interventions, Change Management, Culture Change

No. of Pages: 38

Pilot Performance, Workload, and Usability Considerations for the Use of a Monocular Head-Worn Display in Lieu of a Head-Up Display During SA CAT I Approach, Landing, and Rollout with an Enhanced Flight Vision System

FAA Office of Aerospace Medicine
Civil Aerospace Medical Institute

Report No: DOT/FAA/AM- AM-26/03

Title and Subtitle: Pilot Performance, Workload, and Usability Considerations for the Use of a Monocular Head-Worn Display in Lieu of a Head-Up Display During SA CAT I Approach, Landing, and Rollout with an Enhanced Flight Vision System

Report Date: January 2026

Authors: David C. Newton (0000-0002-3112-3316), Inchul Choi (0000-0002-2048-7026), Hanna Forbat, Rebecca DiDomenica (0009-0009-4726-578X), Farzaneh Shahini (0000-0002-1514-5312), Theodore C. Mofle (0000-0003-2217-9083), and Ryan Weaver

Abstract:
When flying a Special Authorization Category I (SA CAT I) instrument landing system (ILS) approach, pilots may use a Head-Up Display (HUD), which presents flight symbology on a transparent screen so that the pilot can view primary flight information while looking out the window, along the flightpath. Pilots can also use an Enhanced Flight Vision System (EFVS) on a HUD during this operation, which provides a real-time sensor image of the forward view to enhance runway awareness when transitioning to visual flight references. The Head-Worn Display (HWD) is an emerging technology in civil aviation that is designed to provide the benefits of a HUD; however, the unique optical and physical characteristics of the HWD may change the existing levels of pilot performance and workload during SA CAT I operations flown with a HUD. When flying with a monocular HWD, binocular rivalry occurs, which may impact pilot performance and workload. This raises questions about whether pilot performance and workload are significantly impacted during manual SA CAT I flight operations, in which the pilot flying (PF) uses a monocular HWD with and without an EFVS. To address this concern, a study was carried out in which 11 pilot crews, made up of 22 Airline Transport Pilot (ATP) Captains, flew manual SA CAT I approach, landing, and rollout scenarios in a Boeing 737 Level D-equivalent flight simulator with a HUD and monocular HWD, with and without an EFVS, and in day and night ambient lighting conditions. Simulator motion was disabled to prevent interference with the HWD head tracking system. The PF rated their workload during each scenario using the National Aeronautics and Space Administration Task Load Index (NASA-TLX). The findings of the study suggest that a monocular HWD may not have a significant negative impact on a pilot’s ability to manage most aspects of the flightpath during an SA CAT I operation; however, the monocular HWD elevated pilot workload. The monocular HWD also caused increased glideslope deviation during the instrument segment and increased deviation from the runway centerline during rollout. However, these increases were small and may not translate to operational significance. Pilots reported that the EFVS enhanced their awareness of the runway environment when transitioning from instrument to visual flight references; however, because there was not an EFVS kill switch for the PF, it was reported to interfere with natural vision when transitioning to flare, landing, and rollout, regardless of when implemented on a HUD and monocular HWD. Ultimately, this research contributes to the understanding of how SA CAT I operations that are flown with and without an EFVS may be impacted when pilots fly with a monocular HWD in lieu of a HUD.

Key Words: Advanced vision systems, all-weather operations, enhanced vision system, enhanced flight vision system, equivalent visual operations, extended reality, head-mounted display, head-up display, head-worn display, low-visibility operations, pilot performance, pilot workload

No. of Pages: 109

Use of a Monocular and Binocular Head-Worn Display in Lieu of a Head-Up Display During Approach, Landing, and Rollout: Human Factors Evaluation of Pilot Performance and Workload

FAA Office of Aerospace Medicine
Civil Aerospace Medical Institute

Report No: DOT/FAA/AM-26/02

Title and Subtitle: Use of a Monocular and Binocular Head-Worn Display in Lieu of a Head-Up Display During Approach, Landing, and Rollout: Human Factors Evaluation of Pilot Performance and Workload

Report Date: January 2026

Authors: David C. Newton (0000-0002-3112-3316), Eric T. Greenlee (0000-0001-9433-6434), Theodore C. Mofle (0000-0003-2217-9083), Farzaneh Shahini (0000-0002-1514-5312), Rebecca DiDomenica (0009-0009-4726-578X), Inchul Choi (0000-0002-2048-7026), and Ryan Weaver

Abstract:
The approach, landing, and rollout is a complex, critical operation for pilots of fixed-wing aircraft, particularly when flight visibility is limited by weather. To enhance the safety of this operation, aircraft can be equipped with a Head-Up Display (HUD), which presents flight symbology on a transparent screen at a focal distance of optical infinity so that the pilot can view primary flight information while maintaining visual contact with the runway. The Head-Worn Display (HWD) is an emerging technology that is designed to provide the benefits of a HUD. However, it may incorporate optical differences that impact pilots’ performance and workload. HWDs can be binocular (i.e., displaying symbology to both eyes) or monocular (i.e., displaying symbology to a single eye). When flying with a monocular HWD, binocular rivalry may impact the pilot’s ability to use the symbology and impose greater demands on the pilot’s attention. This raises questions about whether using a monocular HWD impacts pilots’ flying performance, elevates workload, and increases the risk of attentional tunneling. Pilot performance and workload may also be impacted by the physical and optical differences of the HWD relative to those of the HUD. To address these concerns, a study was carried out in which 24 pilot crews, each consisting of two Airline Transport Pilot (ATP) Captains, flew approach and landing scenarios with varying visibility levels, some of which included non-normal events, in a Boeing 737 Level D-equivalent flight simulator while using flight symbology presented on a HUD, binocular HWD, and monocular HWD. Simulator motion was disabled in the study to prevent interference with the HWD head tracking system. Quantitative measures of pilot flying performance were implemented to evaluate the effects of each display type on flightpath and energy management, landing and rollout performance, and response to non-normal events. Pilots rated their workload during each scenario using the National Aeronautics and Space Administration Task Load Index (NASA-TLX). The findings of this study suggest that a monocular HWD may not have a substantial impact on a pilot’s ability to manage the flightpath and energy state during approach, landing, and rollout operations. However, pilots experienced a higher workload when flying with the monocular HWD than with the binocular HWD and HUD. There were impacts on landing performance and runway incursion detection attributable to the optical characteristics of the HWD relative to those of the HUD, as well as the monocular versus binocular configuration of the HWD. Ultimately, this research contributes to the understanding of how visual attention is impacted by monocular viewing and provides operational takeaways for the use of an HWD in lieu of a HUD during low-visibility flight operations.

Key Words: Advanced vision systems, binocular rivalry, extended reality, flight technical error, head-mounted display, head-up display, head-worn display, low-visibility operations, pilot performance, pilot response time, pilot workload, runway incursions

No. of Pages: 106

Low Flow / Optimized Flow Oxygen Systems for Passengers

FAA Office of Aerospace Medicine 
Civil Aerospace Medical Institute

Report No: DOT/FAA/AM-25/52

Title and Subtitle: Low Flow / Optimized Flow Oxygen Systems for Passengers – (OFOS) - A Physiologic Inquiry into Emergency Supplemental Oxygen Supply Needs and Procedures

Report Date: 9/1/2025

Authors: Dr. James E. Campbell (ORCID 0000-0002-4062-4710) Dr. Susan M. Jay (ORCID 0000-0002-1331-0396)

Abstract: The OFOS study evaluated SpO2 values and oxygen flow rates via FAA-approved phase-dilution passenger oxygen masks at simulated cabin altitudes between 12K’ and 45K’. Results favor establishment of performance-based, physiological criteria (e.g., range of SpO2 values) that can be used as a minimum performance standard for the minimum mass flow of supplemental oxygen to a passenger mask for adequate hypoxia protection. OFOS data demonstrate significantly higher stable human blood oxygenation levels are maintained through use of a phase-dilution passenger oxygen mask than is required by 14 CFR 25.1443(c)(2) regulation, and a brief transit as a passenger to 45k’ while breathing oxygen from a PAX mask is tolerable (SpO2 does not fall below 14 CFR 25.1443 (c)(2) regulation guidelines). OFOS data support, 1) 14 CFR 25.1443(c)(2) regulation modification in favor of SpO2 focus, 2)use of less oxygen as a result of SpO2 focused findings, 3) fuel/cost-savings, 4) less CO2 emissions, and 5) evidence that passengers are adequately protected under circumstances of a gradual decompression to 45K’ pressure-altitude if exposed for less than 1 minute (validation of FAA Memorandum ANM-03-112-16 (24 MAR 2006)). As a result of this evidence, if more aircraft are type-certified for 45K’ flight, then overall safety will improve as a result of decongested NAS national airspace.

Key Words: Passenger Oxygen Mask Continuous Flow Pressure Altitude Hypobaric Chamber Tracheal Partial Pressure 8025A Ernsting 25.841 25.1443 TSO C64a Decompression TPP Blood Saturation SpO2 45000 45k hematocrit hemoglobin physiology AS5722 human PAX

No. of Pages: 75

Operational and Human Factors Considerations for Synthetic Vision Systems and Head-worn Displays: Results from a Literature Review and Survey

FAA Office of Aerospace Medicine 
Civil Aerospace Medical Institute

Report No: DOT/FAA/AM-26/01

Title and Subtitle: Operational and Human Factors Considerations for Synthetic Vision Systems and Head-worn Displays: Results from a Literature Review and Survey.

Report Date: January 2026

Authors: Kelene A. Fercho, Bryan L. Watson, Dennis B. Beringer, Theodore C.Mofle, Matthew Scheinblum-Brewer

Abstract: This research addressed operational considerations from a human factors perspective for the use of synthetic vision systems (SVSs) implemented on a head-worn display (HWD). Given the increasing use and development of SVSs and aviation HWDs, Federal Aviation Administration stakeholders requested information to identify gaps in knowledge to inform future research requirements, and to identify criteria not presently contained in applicable regulations for pilot training and for evaluating equipment functionality, intuitiveness, and potential hazards. This paper includes an overview of commercially available combined vision systems, enhanced vision systems, and SVSs implemented on an HWD; an overview of published scientific literature on SVSs implemented on an HWD; and results from a survey of 70individuals who reported moderate or greater familiarity with SVSs or HWDs. The purpose of the survey was to solicit expert opinion on industry interest, and on human factors and operational considerations of SVSs implemented on an HWD. Example training topics for the use of SVSs implemented on an HWD are included in the Appendix.

Key Words: Combined Vision System, Enhanced Vision System, Head-mounted Display, External Vision System, Head-worn Display, Human Factors, Literature Review, Pilot Training, Questionnaire, Survey Research, Synthetic Vision System, Synthetic Vision Guidance System.

No. of Pages: 136

Aerospace Medicine Technical Reports