This study addresses this gap by i) developing a structured crosswalk that maps FAA Part 139 requirements to the four pillars of the ICAO Safety Management System (SMS), ii) comparing the regulatory scope, strengths, and limitations of the two oversight approaches to identify areas of overlap and divergence, and iii) proposing a hybrid airport safety oversight framework that integrates prescriptive compliance with performance-based safety management. The overall objective is to provide a conceptual foundation for aligning U.S. airport safety oversight with internationally recognized safety management principles while identifying opportunities for future implementation and evaluation.

The comparative analysis draws upon publicly available regulatory documents, guidance materials, government oversight reports, and operational references to examine the relationship between the FAA Part 139 airport certification framework and the ICAO Safety Management System (SMS). Rather than constructing an airport-level statistical dataset, these sources were used to compare the regulatory scope, oversight philosophy, and practical application of the two frameworks. The primary sources include:

1) FAA Part 139 regulations and associated guidance, which establish airport certification requirements, inspection procedures, operational standards, and Safety Management System (SMS) implementation guidance for certificated airports [2][3][13].

2) ICAO Annex 19, the Safety Management Manual (Doc 9859), and the Universal Safety Oversight Audit Programme (USOAP), which define internationally recognized principles for safety management, safety oversight, and continuous improvement [4][5].

3) Government oversight reports, including publications issued by the U.S. Government Accountability Office (GAO) and the Department of Transportation Office of Inspector General (DOT OIG), which provide independent evaluations of airport safety oversight practices, implementation challenges, and regulatory performance [14].

To provide additional operational and regulatory context, publicly available FAA Safety Management System (SMS) regulations and guidance, Bureau of Transportation Statistics (BTS) operational information, NOAA weather datasets, and ICAO oversight guidance were also reviewed [18]-[23]. These sources were used to illustrate the operational environment in which airport safety oversight is implemented and to support the comparative discussion throughout the paper. They were not used to develop or validate airport-level statistical models, nor were they intended to establish causal relationships between regulatory approaches and safety performance.

A structured crosswalk was developed to compare the prescriptive requirements of FAA Part 139 with the four pillars of the ICAO Safety Management System (SMS): Safety Policy, Safety Risk Management, Safety Assurance, and Safety Promotion. The crosswalk was constructed by reviewing regulatory requirements, guidance documents, and oversight practices to identify areas of regulatory alignment, complementary functions, and differences in oversight philosophy.

Key operational domains addressed under Part 139, including Aircraft Rescue and Firefighting (ARFF), pavement condition, airfield lighting, emergency planning, training, and wildlife hazard management, were systematically mapped to the corresponding SMS pillars based on their primary safety objectives and operational functions [2][5]. The mapping focused on identifying where the two frameworks address similar safety goals through different regulatory approaches and where one framework provides broader coverage than the other.

The conceptual consistency of the crosswalk was verified using the ICAO Safety Management Manual (Doc 9859) and the FAA Airport Safety Management System guidance to ensure that the comparisons reflected the intent of both regulatory frameworks rather than direct regulatory equivalence [5][13]. The resulting crosswalk provides the foundation for comparative analysis and the proposed hybrid airport safety oversight framework presented in this study.

The comparative analysis was conducted to identify areas of convergence and divergence between the FAA Part 139 oversight framework and the ICAO Safety Management System (SMS). The analysis focused on comparing the scope, objectives, and implementation characteristics of each framework rather than evaluating their effectiveness through statistical testing.

The comparison consisted of four complementary components:

1) Regulatory comparison: FAA Part 139 operational requirements were compared with the corresponding ICAO SMS pillars to identify similarities, complementary functions, and differences in regulatory emphasis.

2) Crosswalk assessment: The crosswalk developed in Table 2 was used to evaluate the extent to which individual Part 139 operational domains align with the four SMS pillars and to identify areas where one framework provides broader coverage than the other.

3) Comparative evaluation: The strengths and limitations of both oversight approaches were examined using published regulatory guidance, government oversight reports, and existing literature. Particular attention was given to compliance assurance, hazard identification, organizational safety culture, continuous improvement, and risk management practices.

4) Framework development: Findings from the comparative analysis were synthesized to develop a hybrid airport safety oversight framework that combines the structured compliance requirements of FAA Part 139 with the proactive safety management principles of ICAO SMS.

Table 2. Conceptual crosswalk between FAA Part 139 operational domains and the four pillars of the ICAO Safety Management System (SMS), illustrating areas of regulatory alignment, complementary functions, and opportunities for integration within a hybrid airport safety oversight framework.

This study is based exclusively on publicly available regulatory documents, guidance materials, government reports, and operational references. No proprietary, confidential, or personally identifiable information was collected or analyzed. Because the study presents a conceptual comparison of existing regulatory frameworks, it did not involve human participants, human subjects research, or the use of restricted datasets. The research was conducted in accordance with accepted academic standards for the use and citation of publicly available information. Figure 2 presents the overall research methodology adopted in this study, including source selection, crosswalk development, comparative analysis, and framework development.

Figure 2. Overview of the study methodology showing the sequential process of source selection, crosswalk development, comparative analysis, and development of the proposed hybrid airport safety oversight framework.

The comparative review of FAA Part 139 and the ICAO Safety Management System (SMS) indicates that the two frameworks address airport safety through complementary regulatory approaches. FAA Part 139 establishes prescriptive operational requirements supported by standardized inspections, providing a consistent baseline for compliance in critical safety areas such as Aircraft Rescue and Firefighting (ARFF), pavement condition, airfield lighting, emergency planning, and wildlife hazard management [2]. These requirements promote uniform implementation and regulatory consistency across certificated airports.

In contrast, the ICAO SMS framework emphasizes continuous safety management through proactive hazard identification, safety risk management, safety assurance, and safety promotion [4][5]. Rather than replacing prescriptive oversight, SMS expands the scope of safety management by encouraging continuous monitoring, organizational learning, and the integration of safety into everyday operational decision-making.

The comparison suggests that the strengths of one framework complement the limitations of the other. While FAA Part 139 provides clear regulatory requirements and standardized compliance mechanisms, ICAO SMS offers greater flexibility for managing emerging operational risks and strengthening organizational safety culture. These observations provide the foundation for the conceptual crosswalk and the hybrid airport safety oversight framework presented in the following sections.

The crosswalk presented in Table 2 compares the principal operational domains of FAA Part 139 with the four pillars of the ICAO Safety Management System (SMS). The comparison demonstrates that both frameworks share the common objective of improving airport safety, although they achieve this objective through different regulatory approaches.

Strong alignment is observed in areas related to Safety Assurance and Safety Policy, where FAA Part 139 establishes detailed operational requirements for inspections, documentation, emergency preparedness, and Aircraft Rescue and Firefighting (ARFF) readiness. These requirements provide a structured compliance framework that promotes consistency across certificated airports.

The comparison also identifies complementary areas where ICAO SMS extends beyond prescriptive compliance. In particular, Safety Risk Management and Safety Promotion emphasize proactive hazard identification, continuous monitoring, organizational learning, and the development of a positive safety culture. These elements strengthen an organization’s ability to identify emerging risks before they result in operational deficiencies.

Figure 3. Conceptual crosswalk illustrating the relationship between major FAA Part 139 operational domains and the four pillars of the ICAO Safety Management System (SMS). Green indicates strong alignment, yellow indicates partial alignment, and red indicates areas where additional integration opportunities exist within the proposed hybrid airport safety oversight framework.

Overall, the crosswalk demonstrates that the two frameworks are complementary rather than competing. FAA Part 139 provides the regulatory foundation for operational compliance, while ICAO SMS introduces management processes that enhance adaptability, continuous improvement, and long-term safety performance. These findings support the development of the hybrid airport safety oversight framework proposed in this study. Figure 3 presents the conceptual crosswalk between FAA Part 139 operational domains and the four pillars of the ICAO Safety Management System (SMS).

The comparative evaluation of FAA Part 139 and the ICAO Safety Management System (SMS) highlights the complementary strengths of the two oversight approaches. FAA Part 139 provides a structured regulatory framework built on standardized operational requirements and inspections, ensuring consistent compliance in critical safety areas such as runway pavement condition, airfield lighting, wildlife hazard management, emergency planning, and Aircraft Rescue and Firefighting (ARFF) readiness [2]. This prescriptive approach establishes a uniform baseline for airport safety oversight.

In contrast, ICAO SMS focuses on the organizational processes that support long-term safety performance. Through safety risk management, safety assurance, safety promotion, and continuous monitoring, SMS encourages airport operators to identify hazards proactively, strengthen organizational learning, and continuously improve safety performance [4][5].

The crosswalk demonstrates that these approaches are not mutually exclusive. Instead, they address different aspects of airport safety oversight. While Part 139 establishes clear regulatory expectations and compliance mechanisms, SMS provides a structured management framework for addressing evolving operational risks and strengthening safety culture. Together, these complementary characteristics support the development of a hybrid airport safety oversight framework that combines regulatory consistency with proactive safety management.

The comparative analysis indicates that neither FAA Part 139 nor the ICAO Safety Management System (SMS) fully addresses all aspects of airport safety oversight. The proposed hybrid framework is intended to provide a more comprehensive approach to airport safety oversight by integrating the complementary strengths of both approaches. FAA Part 139 provides a well-defined regulatory structure that supports consistent implementation, standardized inspections, and accountability across certificated airports. In contrast, ICAO SMS emphasizes organizational learning, proactive hazard identification, continuous safety assurance, and the development of a positive safety culture.

These observations support the need for an oversight approach that integrates the regulatory consistency of Part 139 with the adaptive management principles of SMS. Such an approach can strengthen the ability of airport operators and regulators to address both established operational requirements and emerging safety challenges while maintaining alignment with national and international safety objectives.

The findings presented in this study are based on a comparative review of regulatory frameworks and published guidance rather than statistical validation. Consequently, the proposed hybrid framework should be viewed as a conceptual model that provides a foundation for future empirical evaluation and practical implementation within airport safety oversight programs.

The comparative analysis demonstrates that FAA Part 139 and the ICAO Safety Management System (SMS) provide complementary approaches to airport safety oversight. FAA Part 139 establishes a consistent regulatory foundation through standardized operational requirements and compliance-based inspections, particularly in high-consequence areas such as Aircraft Rescue and Firefighting (ARFF), pavement condition, airfield lighting, and emergency preparedness [2]. In contrast, ICAO SMS broadens the scope of safety oversight by emphasizing proactive hazard identification, continuous safety assurance, organizational learning, and the promotion of a positive safety culture [4][5].

The crosswalk analysis indicates that integrating these complementary strengths can support a more balanced and adaptive oversight approach. Based on these findings, this study proposes a hybrid airport safety oversight framework that combines the structured compliance mechanisms of FAA Part 139 with the proactive management principles of ICAO SMS. The proposed framework provides a practical foundation for strengthening airport safety oversight while supporting future implementation and evaluation.

1) Prescriptive Baseline Controls

High-consequence operational areas, including Aircraft Rescue and Firefighting (ARFF) readiness, pavement condition, airfield lighting, emergency planning, and wildlife hazard management, should continue to be governed by the prescriptive requirements established under FAA Part 139 [2]. These requirements provide a consistent regulatory foundation and ensure that minimum safety standards are maintained across certificated airports.

2) Performance-Based Safety Management

Complementing these regulatory requirements, ICAO SMS principles should be incorporated to strengthen hazard identification, safety risk management, continuous safety assurance, and safety promotion [5]. These processes enable airport operators to address emerging operational risks proactively while supporting continuous organizational learning and improvement.

3) Integrated Safety Oversight: Some Operational Domains Require Both Approaches

A hybrid oversight approach combines prescriptive compliance activities with performance-based safety management to support a more comprehensive oversight system. Regulatory inspections verify compliance with established requirements, while SMS processes provide continuous monitoring, internal evaluation, and proactive management of safety risks.

4) Continuous Safety Improvement

The integration of compliance-based oversight and performance-based management encourages continuous evaluation of airport safety performance. Safety reporting, organizational learning, leadership engagement, and periodic review of safety practices contribute to the ongoing improvement of airport safety oversight while maintaining regulatory consistency.

The proposed hybrid airport safety oversight framework is organized as a two-layer structure that combines regulatory compliance with continuous safety management. Each layer performs a distinct function while supporting the overall objective of strengthening airport safety oversight.

The first layer consists of the prescriptive oversight activities established under FAA Part 139, including airport inspections, operational requirements, documentation, and compliance verification. These activities provide a consistent regulatory baseline for certificated airports and ensure adherence to established safety standards.

The second layer incorporates the principles of the ICAO Safety Management System (SMS), including safety risk management, safety assurance, safety promotion, and continuous monitoring. These processes complement regulatory oversight by encouraging proactive hazard identification, organizational learning, and continuous improvement.

Together, the two layers create an integrated oversight approach in which compliance verification and performance-based safety management reinforce one another. The resulting framework supports regulatory consistency while providing the flexibility needed to address evolving operational risks and strengthen long-term airport safety performance. Figure 4 illustrates the proposed hybrid airport safety oversight framework developed from the comparative analysis.

Figure 4. Proposed hybrid airport safety oversight framework integrating prescriptive FAA Part 139 oversight with performance-based ICAO Safety Management System (SMS) processes.

The decision matrix presented in Table 3 illustrates how different airport safety domains may benefit from different oversight approaches based on their operational characteristics. Rather than relying exclusively on either prescriptive compliance or performance-based safety management, the matrix demonstrates where each approach provides the greatest value and where a hybrid strategy offers the most balanced solution.

High-consequence operational areas that require standardized procedures and regulatory consistency are best managed through prescriptive oversight. In contrast, organizational and human-factor-related issues benefit from performance-based safety management, which emphasizes continuous monitoring, hazard identification, and organizational learning. Certain operational domains benefit from integrating both approaches, where regulatory compliance establishes minimum safety standards while SMS processes enhance proactive risk management and continuous improvement.

The decision matrix serves as a practical reference for regulators and airport operators when selecting the most appropriate oversight strategy for different airport safety functions. It also demonstrates how the proposed hybrid framework can be applied across a range of operational environments while maintaining consistency with both FAA Part 139 requirements and ICAO SMS principles.

Table 3. Decision matrix for selecting the appropriate oversight approach for major airport safety domains within the proposed hybrid airport safety oversight framework.

The proposed hybrid airport safety oversight framework offers practical implications for both regulators and airport operators. By integrating the structured compliance requirements of FAA Part 139 with the proactive management principles of the ICAO Safety Management System (SMS), the framework supports a more comprehensive approach to airport safety oversight while maintaining consistency with existing regulatory requirements [24].

For regulators, the framework provides a structured basis for incorporating performance-based safety management into established oversight activities without replacing the prescriptive controls that remain essential for high-consequence operational areas. For airport operators, it encourages greater integration of hazard identification, safety assurance, organizational learning, and continuous improvement within daily operations [9].

More broadly, the proposed framework supports continued alignment between U.S. airport safety oversight and internationally recognized safety management practices. By promoting both regulatory consistency and proactive safety management, the framework contributes to stronger organizational resilience, improved safety governance, and a more adaptive approach to managing evolving operational risks. It also provides a practical foundation for future implementation, evaluation, and refinement as airport safety oversight continues to evolve.