Emerging Hazards in
Commercial Aviation—
Report 3

The Human Contribution to Safety

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Committee on Emerging Trends in Aviation Safety

Transportation Research Board

Consensus Study Report

Transportation Research Board Special Report 361

Subscriber Categories: Aviation; safety and human factors

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This study was sponsored by the Federal Aviation Administration.

International Standard Book Number-13: 978-0-309-60557-1
Digital Object Identifier: http://doi.org/10.17226/29420

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COMMITTEE ON EMERGING TRENDS IN AVIATION SAFETY

AMY R. PRITCHETT (Chair), The Pennsylvania State University

ANN M. BISANTZ, State University of New York at Buffalo

DONALD E. BROWN, University of Virginia

SHERYL CHAPPELL, Private Consultancy

CODY H. FLEMING, Iowa State University

R. JOHN HANSMAN, JR., Massachusetts Institute of Technology

CHRISTOPHER A. HART, Hart Solutions LLC

KAREN MARAIS, Purdue University

PAUL MCCARTHY, International Federation of Air Line Pilot’s Associations

SHWETA MULCARE, SAIC, Inc.¹

ASHOK N. SRIVASTAVA, Intuit

KATHLEEN M. SUTCLIFFE, Johns Hopkins University

TIMOTHY J. VOGUS, Vanderbilt University

Study Staff

LIDA BENINSON, Study Director, Consensus and Advisory Studies, Transportation Research Board

STEPHEN GODWIN, Scholar, Consensus and Advisory Studies, Transportation Research Board

THOMAS R. MENZIES, JR., Director, Consensus and Advisory Studies, Transportation Research Board

MARK HUTCHINS, Senior Program Officer, Consensus and Advisory Studies, Transportation Research Board

TIMOTHY MARFLAK, Program Coordinator, Consensus and Advisory Studies, Transportation Research Board

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¹ Member of the committee through October 2025.

Reviewers

This consensus study report was reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise. The purpose of this independent review is to provide candid and critical comments that will assist the National Academies of Sciences, Engineering, and Medicine (National Academies) in making each published report as sound as possible and to ensure that it meets the institutional standards for quality, objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process.

We thank the following individuals for their review of this report:

JOHN-PAUL CLARKE (NAE), University of Texas at Austin

HELENA CUNNINGHAM, Air Line Pilots Association, International

BECK HOOEY, NASA Ames Research Center

ZHIKA LEI, Pepperdine University and International Institute for Management Development (IMD) Business School

JANA PRICE, National Transportation Safety Board

JOSEPH SOBIERALSKI, Embry-Riddle Aeronautical University

ROBERT SUMWALT, Embry-Riddle Aeronautical University

LANCE WALLER, Emory University

Although the reviewers listed above provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations of this report, nor did they see the final draft before its

release. The review of this report was overseen by CHRIS HENDRICKSON (NAE), Carnegie Mellon University, and CRAIG PHILIP (NAE), Vanderbilt University. They were responsible for making certain that an independent examination of this report was carried out in accordance with the standards of the National Academies and that all review comments were carefully considered. Responsibility for the final content rests entirely with the authoring committee and the National Academies.

Acknowledgments

The committee appreciates the support of the Federal Aviation Administration (FAA) staff in providing background information related to the Commercial Aviation Safety Team, the Aviation Safety Information Analysis and Sharing program, and the Annual Safety Culture Survey. The committee also thanks senior librarians Anne Marie Houppert and Rebecca Morgan, as well as the National Academies’ research library, for assistance with fact checking and literature searches.

This report was developed under the overall supervision of Thomas R. Menzies, Jr., Director of Consensus and Advisory Studies, Transportation Research Board (TRB). Lida Beninson, Senior Program Officer, TRB, served as the study director. She and Stephen Godwin, Scholar, TRB, assisted the study committee in the preparation of this report. Timothy Marflak of TRB provided support to the committee in arranging meetings.

The committee would like to thank the following individuals for providing input to this study:

HELENA CUNNINGHAM, Air Line Pilots Association

BARBARA HOLDER, Embry-Riddle Aeronautical University

CARL MACRAE, University of Nottingham

JAMES STARNES, Airline Dispatcher Federation

DIANE VAUGHAN, Columbia University

Contents

PREFACE

ACRONYMS AND ABBREVIATIONS

EXECUTIVE SUMMARY

1 INTRODUCTION

Beyond Preventing Human Error

Emerging Workforce Trends

Report Organization

References

2 A CHANGING AVIATION WORKFORCE THAT COULD MATTER TO SAFETY

Changes in Workforce Size and Occupational Experience

Training and Preparation

Changing Workforce Pipeline

Chapter Summary and Recommendation

References

3 THE HUMAN CONTRIBUTION TO SAFETY ACROSS INDIVIDUALS, TEAMS, AND ORGANIZATIONS

Contributions as Individuals

Contributions as Teams

Contributions as Organizations

Chapter Summary

References

4 DATA ANALYSIS TO MONITOR, ASSESS, AND ACT UPON EMERGING WORKFORCE TRENDS THAT COULD AFFECT AVIATION SAFETY

Data Available for Enhanced Safety Analysis

New Data Analysis Techniques

Exemplar Use Cases of Transformative Aviation Safety Analysis

Longitudinal Assessment of Line-Oriented Flight Training and Similar Training Programs

Chapter Summary and Recommendations

References

5 FAA’S AVIATION SAFETY ORGANIZATION SAFETY CULTURE ASSESSMENT

AVS Briefings on Its Safety Culture Assessment

Assessment of AVS Safety Culture Maturity

Oversight of ATO

References

6 OVERALL ASSESSMENT

APPENDIX: Study Committee Biographical Information

Box and Figures

BOX

1-1 Statement of Task

FIGURES

2-1 Age distribution of first-class medical certificate holders for airline transport certified pilots as of March 17, 2026

2-2 Distribution of Certified Professional Controllers’ years of service, FY 2010 and FY 2024

2-3 Age distribution of the air traffic controller workforce, 2024 and 2006

Preface

The safety of the U.S. National Airspace System depends not only on aircraft, technologies, and infrastructure, but also on the performance of the people who operate, maintain, regulate, and oversee it. Pilots, air traffic controllers, mechanics, and dispatchers have a direct role in ensuring flight performance and the prevention of operational failures, while many other occupations, including flight attendants, inspectors, and certifiers, also provide safety-critical functions. As this workforce changes over time, it is essential to understand how those changes may influence aviation safety.

Section 132 of the Aircraft Certification, Safety, and Accountability Act of 2020¹ directed the National Academies of Sciences, Engineering, and Medicine to conduct a 10-year series of studies examining emerging hazards in commercial aviation. The studies are intended to identify, categorize, and analyze emerging safety trends and to provide Congress, the Federal Aviation Administration, industry, and other stakeholders with advice on improving the identification, monitoring, understanding, and mitigation of aviation safety risks.

This report is the third in that series. Whereas the first report examined aviation safety data sources and analytic methods for identifying emerging risks, and the second examined safety during transformative changes in aircraft technologies and operations, this report focuses on the human contribution to safety. It examines how changes in the commercial aviation workforce may affect safety, how operational and safety data can be used

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¹ Section 132 of the Aircraft Certification, Safety, and Accountability Act of 2020 (enacted as Division V of the Consolidated Appropriations Act, 2021, Pub. L. 116-260).

to detect and monitor those effects, and how safety culture supports safe operations and effective regulatory oversight.

An interdisciplinary committee with expertise in aviation operations, human factors, safety management, organizational behavior, engineering, data analytics, and regulatory oversight conducted this study. The committee gathered information through technical briefings, reviews of scientific and professional literature, and analyses of relevant data sources. The findings and recommendations presented in this report represent the consensus judgment of the committee’s members, who served without compensation in the public interest.

Acronyms and Abbreviations