Office of the Administrator 

January 21, 2021 

Dr. R. John Hansman, Ph.D. 

Chair, Research, Engineering and 

 Development Advisory Committee 

Dear Dr. Hansman: 

Thank you and the Federal Aviation Administration's (FAA) Research, Engineering, and 

Development Advisory Committee (REDAC) for your October 30, 2020, letter providing 

recommendations on the Fiscal Year (FY) 2023 Research and Development (R&D) Portfolio. 

We sincerely appreciate the important guidance generated during the REDAC Summer-Fall 2020 

virtual meeting, held on October 7, 2020. 

Meeting discussions concerning the impact of COVID-19 on FAA Research and Development 

(R&D) programs were timely and appropriate. I look forward to additional dialog on future 

automation and technologies within aviation and aerospace involving Machine-Learning, 

Artificial Intelligence, and human-machine interfaces. Additionally, we greatly appreciated the 

engagement regarding the FAA Landscape drivers as it will assist in identifying research 

priorities and enhance our collaborative efforts with industry. 

We have reviewed the eighteen recommendations you offered and the enclosed FAA Response 

Report reflects our proposed dispositions and action plans. 

I appreciate your assessment and insightful advice as well as the expertise of the REDAC 

professionals who continue to provide valuable guidance and support of the Agency’s R&D 

programs. 

Sincerely, 

Steve Dickson 

Administrator 

Enclosure 
FAA Response to Research, Engineering and Development Advisory Committee 

(REDAC) Guidance for the Fiscal (FY) Year 2023 Research and Development Portfolio 

Subcommittee on Airports 

General Observations and Commendations:

The Subcommittee appreciated the FAA’s update regarding how the COVID-19 pandemic has

affected program research in the Spring and Summer of 2020. The closure of the FAA Technical

Center facilities and the extenuating impacts COVID-19 has had on program contractors and

university partners have had consequential impacts on key research projects, including projects 

that undertaken in response to research requested by Congress in the FAA Reauthorization Act

of 2018.

We are particularly concerned about research regarding (1) unmanned aircraft system (UAS) use 

at airports, (2) UAS detection and mitigation systems, and (3) alternatives to aqueous film 

forming foam (AFFF) used in aircraft rescue and fire-fighting (ARFF) applications. 

The Subcommittee was pleased to learn that, despite COVID impacts, the FAA has moved 

forward with important elements of several ongoing research projects. These include preparation 

of broad agency announcements for vendors and airports for UAS detection and mitigation 

system evaluations, establishment of an industry expert group regarding alternative firefighting 

agents, and completion of several safety and pavement projects for which laboratory work had 

finished or was unnecessary. 

As we noted in our May 2020 report, the Subcommittee recognizes that the impacts COVID-19 

has had and will continue to have on the aviation industry are broad and severe. We also 

recognize that these impacts—and associated research needs to address them—may require both 

new research activities and reprioritization of current research priorities. The Subcommittee 

stands ready to assist the FAA with these efforts as the pandemic and our collective response 

efforts evolve and mature. 

We commend the Program’s research efforts to support statutory mandates in the FAA 

Reauthorization Act of 2018. These mandates include Sections 136 and 183 regarding the use of 

state highway pavement specifications for airfield pavements, Section 146 regarding the use of 

retroreflective glass beads for airfield marking conspicuity, and Section 525 regarding the use of 

geotextiles for airport pavement applications. Program research into these topics have enabled 

the FAA to revise its guidance to airports in all three areas. 

The Subcommittee also commends the FAA for its release of Version 2.0 of FAARFIELD0F

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, the 

FAA’s pavement thickness design software. The software was in need of the update to make it a 

more user-friendly and consistent with other engineering software in the public domain. The 

FAA released Version 2.0 of the software in June. It incorporates a new user interface, a new 

finite element computational library, an updated aircraft library, and incorporation of new 

International Civil Aviation Organization (ICAO) pavement assessment criteria. The 

Subcommittee looks forward to future FAARFIELD enhancements to address other key 

 1 FAARFIELD = FAA Rigid and Flexible Iterative Elastic Layered Design. 
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pavement design issues including top-down cracking failure criteria for rigid pavements and 

vertical strain in asphalt layers for flexible pavements. 

Finding: COVID – 19 Research Impacts - The Subcommittee recognizes that disruptions 

caused by the COVID-19 pandemic have delayed time-critical research activities, including 

those associated with provisions in the FAA Reauthorization Act of 2018. The Program’s 

alternative firefighting agent research project is of particular concern because: 

• The Project’s findings are needed to support FAA action regarding Section 332 of the 

FAA Reauthorization Act of 2018. Section 332 permits use of non-fluorinated chemicals 

for aircraft firefighting provided they meet applicable FAA and National Fire Protection 

Association (NFPA) performance standards.

• Airport operators are under considerable pressure from state and local governments and 

local communities to reduce or eliminate use of PFAS at airports.

• There are significant and growing concerns about the human health impacts and 

associated liability associated with PFAS contamination on and near airports.

The Subcommittee also recognizes the need for the FAA’s efforts to be coordinated closely with 

complementary research efforts that have been underway within the U.S. Department of 

Defense. 

Recommendation 1: With respect to the alternative firefighting agent research project, the 

Subcommittee recommends that the FAA carefully monitor research timelines in light of 

COVID-19 delays, prioritizing those activities associated with Congressional deadlines. The 

FAA should keep the Subcommittee and Congressional liaisons informed about the status of the 

research and the ability to meet the aforementioned deadlines. 

FAA Response: The FAA concurs with the Committee’s findings and recommendations and is 

taking the following actions to address it - Testing of alternative firefighting agents resumed late 

August 2020 at the ARFF research facility. The FAA has since then maintained strict control of 

the testing schedule and is progressing as rapidly as possible. The FAA will keep the 

Subcommittee informed about the overall status of the research and other technical developments 

as testing progresses. 

Finding: Emerging Pavement Additives - The Subcommittee generally supports the research 

into emerging pavement additives (e.g., carbon nanotubes mixed into cementitious materials to 

promote self-monitoring concrete pavements to see if damage in the micro-structure of 

pavements is occurring). While the Subcommittee realizes the useful potential of these 

additives, we note that consideration needs to be given to how these particles affect full-scale 

pavement construction. 

Recommendation 2: The Subcommittee recommends the FAA consider evaluating emerging 

pavement additives in the National Airport Pavement Testing Facility test facility during future 

construction cycles, inclusive of assessing impact the additives have on the full-scale production 

of concrete during placement, consolidation, and finishing. 
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FAA Response: The FAA concurs with the Committee’s findings and recommendations and is 

taking the following actions to address it - The FAA will consider evaluating emerging pavement 

additives at the National Airport Pavement Testing Facility (NAPTF). This will be done by 

potentially incorporating these evaluations and developing specific testing plans in future 

NAPTF construction cycles. This would include an assessment of the impact that additives have 

on the full-scale production of concrete during placement, consolidation, and finishing. 

Finding: Airport Technology Research Program - The Subcommittee remains very interested 

in the Airport Technology Research Program’s involvement in UAS research—both from the 

perspective of their beneficial use at and near Airports and from the perspective of managing the 

safety and security risks associated with unauthorized use of these and near airports. We also 

recognize the growing interest in advanced air mobility systems (AAM)—also known as urban 

air mobility systems. AAM, like UAS, represent a new class of aircraft that will need to share 

use of airspace on and near airports. 

Recommendation 3: We continue to recommend that the Airport Technologies Research 

Program utilize the Subcommittee to provide airport stakeholder input and insight into its UAS 

and AAM research activities, as well as in crosscutting research undertaken elsewhere within 

FAA. 

FAA Response: The FAA concurs with the Committee’s findings and recommendations and is 

taking the following actions to address it - Although certain field and testing activities have been 

hampered by the general COVID situation, it is planned that UAS and AAM research activities 

will increase over time. At appropriate times, the Airport Technology Research’s staff (ATR) 

will reach out to the Subcommittee to leverage the Subcommittee’s expertise and to gather 

airport stakeholder input and insight into these activities. 

Subcommittee on Human Factors 

General Observation: Capture Lessons Learned from COVID-19 Pandemic - 

The COVID-19 pandemic has introduced an opportunity to capture experiences, challenges, and 

successes associated with a major global disruption to the aviation sector. The Subcommittee 

applauds the FAA for their participation in the global response to ensure a smooth transition 

back to full operations. The Subcommittee believes there is an opportunity to collect data and 

promote best practices from successes and identify gaps from these challenges. The 

Subcommittee encourages the FAA to collect experiences on how organizations and operations 

are adapting to change and identify ways to be resilient and proactive in the face of uncertainty. 

Data on these experiences can enable the FAA to identify and mitigate HF-related risks 

associated with adapting to and recovering from global disruptions such as the COVID-19 

pandemic. 

Finding: Data Analytics for Operational Personnel -The implementation of many NextGen 

initiatives, such as Trajectory Based Operations, drives a tighter coupling of the tasks performed 

by different FAA facilities. In order to improve inter-facility coordination in such cases, 

improved data analytics support for operator feedback is required. It is important to identify 

requirements that ensure operational personnel at each facility receive effective visibility into 
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operational performance issues. These requirements need to identify both the information 

necessary to detect coordination issues and the analyses necessary to diagnose the causes. 

Recommendation 1: The FAA should conduct research to identify those TBO initiatives where 

an effective learning feedback loop is needed to coordinate process improvements across 

facilities. The research should propose potential information requirements to provide operational 

personnel with the feedback necessary to detect weaknesses in inter-facility coordination and to 

diagnose the underlying causes. 

Consequences: Without improved data analytics for operator learning and training, the FAA will 

not be able to identify NextGen initiatives that may result in inter-facility inefficiencies and their 

associated causes. 

FAA Response: The FAA concurs with the Committee’s finding and recommendation and is 

undertaking the following actions to address its recommendation - The FAA recognizes that 

many Trajectory-Based Operations (TBO) capabilities improve NAS efficiency across the entire 

aircraft trajectory, and that successful implementation of these capabilities may be improved 

through air traffic decisions that reflect cross-facility considerations. The FAA is currently 

planning two Human Factors research projects related to TBO training and TBO decision 

making, both of which relate to cross-facility considerations. From these research projects and 

any other new or existing research, opportunities for TBO operator learning and training will be 

presented at the next two Human Factors Subcommittee meetings (Winter/Spring 2021, and 

Summer/Fall 2021). 

Finding: Workforce Proficiency Training Requirements and Risks of Skill Degradation -

The COVID-19 pandemic has resulted in reduced operations, driving furloughs, repurposing 

aircraft from passenger to cargo, and rapid storage and de-storage of aircraft. The operational 

workforce (e.g. air traffic controllers, maintainers, and pilots) is experiencing backlogs in 

training, extended periods of work inactivity, increased time periods since training or 

requirements for retraining. To ensure continuity of operations, there have been temporary 

extensions of personnel certifications, and new-personnel certification in the current low-traffic 

environment. However, we do not know how these disruptions affect and exacerbate the issues 

associated with workforce proficiency. 

For example, pilot training footprints have remained relatively stable over recent decades despite 

an increasing volume of learning objectives. A “one size fits all” approach has been in place for 

decades; for example, the long-standing currency requirements (such as 3 landings in 90 days), 

or the traditional 14 CFR part 121 subpart O periodicities of 6 months between recurrent training 

events for Captains and 12 months for First Officers. Many operators rely heavily on Advanced 

Qualification Program data to justify and maintain current footprints while adding more content 

into the scheduled time. However, stability of pass rates and task level performance grades do 

not provide sufficient insight into the underlying questions of knowledge and skill retention. 

Similar issues exist for other workforce groups such as maintainers and controllers. 
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To understand the effectiveness of existing training/proficiency requirements and programs, the 

FAA needs scientific human performance data. The aviation industry simply does not data to 

determine how long workforce (e.g. operators and maintainers) skills and knowledge are 

retained, and this issue is exacerbated by COVID-19. 

Recommendation 2: The FAA should conduct research to determine realistic, justifiable, 

training quantities and frequencies, to inform realistic assessment of current training footprints 

and intervals, guidance on practice needed to maintain proficiency, and means to restore 

proficiency after time away from work. 

Consequences: Because training is expensive, there is an economic motive to keep training 

footprints as small as possible; no operator will voluntarily increase their footprint over what is 

either required by regulation or generally accepted as “industry standard,” because to do so 

would put them at an economic disadvantage compared to their competitors. Without scientific 

data to define proficiency retention, the FAA may not have the data needed to determine the 

suitability of training footprints and intervals. The FAA may continue to rely on training 

standards and requirements that do not address widespread skill degradation risks, such as from 

pandemics. 

FAA Response: The FAA concurs with the Committee’s recommendation(s) and with the noted 

exceptions and clarifications intends to undertake the following actions to address its 

recommendation - The FAA agrees that scientific studies would be needed to inform any 

changes to current standards or guidance related to maintaining or restoring operator proficiency, 

but first needs evidence that current requirements and best practices are insufficient. The FAA 

will consider establishing whether such evidence exists, such as from historical events that 

caused extended operator time away from work. The FAA also has managed multiple research 

projects related to skill and knowledge degradation in both the aircraft and air traffic domains. 

Therefore, the FAA will lead a detailed technical discussion with the REDAC Human Factors 

Subcommittee on this topic that includes a) key findings from past and current HF research from 

within the four HF research portfolios, and b) potential ways to gather evidence that current 

proficiency requirements and best practices are insufficient. This discussion will be conducted at 

the next Human Factors Subcommittee meeting (Winter/Spring 2021), and will serve to inform 

further research considerations on this topic. 

Subcommittee on Aircraft Safety 

General Observations: During the REDAC Subcommittee on Aircraft Safety (SAS) meeting, 

FAA presented a series of updates and a review of the R&D program accomplishments. It was 

observed that many of the R&D efforts have the potential to support on-going developments in 

industry, especially many of the new entrants to aviation. Given the international scope of 

aviation today, it will be important for the FAA to collaborate with other regulators to find a 

common set of requirements and how those requirements can be used as a means of compliance 

to the regulations. This will allow companies to develop aircraft and systems that will be 

accepted worldwide. In addition, it will be important for the FAA to build on the R&D efforts to 
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collaborate closely with industry to establish a solid regulatory framework for this new 

technology. This is critical for innovation and bring new entrants into the aviation eco-system. 

Finding: FAA’s R&D Efforts during COVID-19 Pandemic - The REDAC SAS received 

briefings on the FAA’s R&D program developments. It was clear that tremendous progress has 

been made during the past six months, in spite of the challenges of COVID-19. Industry 

representatives on the SAS were impressed at that progress and commend the FAA for its efforts 

during this pandemic. While significant progress has been achieved during these unprecedented 

times in our nation’s history, from a long-term perspective, to meet the needs of the industry, a 

continued focus on the R&D program will be imperative. The Committee was briefed on the 

COVID-related suspension of all FAA human subjects’ research; the potential for budgetary and 

programmatic disruption is of concern. In addition to the COVID-19 situation, both industry and 

the FAA have had the additional burden of dealing with the outcomes of the Boeing 737MAX 

re-certification effort. As further lessons are learned from the investigation and subsequent 

reengineering requirements, the potential exists to put new priorities on the R&D program. 

Recommendation 1: As the FAA continues its R&D work program, the REDAC SAS further 

encourages the continued focus on those funded programs. The REDAC SAS requests regular 

updates to any programs that may be negative impacted by the COVID-19 crisis, including 

replanting of milestones and areas where the REDAC SAS can assist. 

FAA Response: The FAA concurs with the Committee’s recommendation and is undertaking the 

following actions to address its recommendation - The FAA will provide an update on the 

COVID-19 impacts on its R&D plans and execution at the SAS Spring 2021 meeting and 

subsequent meetings as appropriate. 

Recommendation 2: As progress is made on the recertification of the 737MAX, at the 

appropriate time the REDAC SAS requests a briefing on what lessons have been learned and the 

impact they are having on the FAA’s R&D portfolio and any changes to its priorities. 

FAA Response: The FAA concurs with the Committee’s recommendation and is undertaking the 

following actions to address its recommendation - The FAA plans to incorporate lessons learned 

from the Boeing 737 MAX into our Accident Lessons Learned database as they are completed. 

The FAA will provide an update on the Boeing 737 Max lessons learned at a future REDAC 

SAS meeting at the appropriate time. 

Finding: Fatigue Risk Management R&D Portfolio - At the Fall 2020 REDAC SAS meeting, 

the Subcommittee received an update on the FAA’s research efforts focusing on aircrew fatigue. 

This followed a similar briefing during the Spring 2020 meeting. The Subcommittee continues 

to be impressed with the dedication of the researchers briefing their fatigue research, and notes 

efforts to bring together fatigue-related research from different policyholders, funding programs, 

and research organizations within the FAA. Notably, the overdue addition of rotary-wing 

aviation operations to the fatigue working group is recognized. 

The SAS recognizes that efforts are ongoing to provide a) a fatigue research program that 

provides a method of surveillance for early indicators of fatigue hazards across aviation 

operations in U.S., and b) a structured research program to assess the effectiveness of Fatigue 

Risk Management Program/Fatigue Risk Management System (FRMP/FRMS) in Part 121 
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passenger-carrying operations. Dr. Nesthus briefed two proposed studies into the fatigue issue, 

one dealing with short haul flying and the other on circadian shift during long haul operations. 

Dr. Nesthus also stated that due to funding constraints, emphasis would be placed on 

accomplishing the short haul study initially due to the level of risk and the current gaps in 

existing research. The Subcommittee agrees with this reasoning and that the short haul study 

should be done first. 

However, despite the FAA’s apparent support for the Fatigue Management Working Group 

(FMWG) and for increased fatigue research, the SAS made two observations: 1) there still does 

not appear to be any planned research aimed at reviewing the existing FRMP/FRMS program to 

assess its performance in long-haul commercial aviation operations. Such research could take 

the form of surveys, event reports, accident reviews, data analysis, etc. 2) SAS Subcommittee 

received budgetary information showing that several fatigue research requirements, including the 

two studies mentioned above, are unfunded in FY2022. The researchers indicate that these 

studies may be suspended due to lack of continued funding. 

The FAA’s method of annually re-prioritizing research and funding on multi-year projects can 

negatively impact the methodology and study design if there is a year-long or more break in the 

study. Furthermore, since FRM research involves volunteer human subjects, there is an 

underlying personal risk those individuals subject themselves to when participating in a study. If 

that study is subsequently canceled or postponed, they have then been exposed to that risk for no 

reason. The Subcommittee hopes that funding reforms in the FAA will correct this problem. 

Recommendation 3: The Subcommittee would like to see additional information on the FAA’s 

fatigue-related projects to enable a better understanding of funded research objectives and 

deliverables. The SAS is requesting an update at the Spring 2021 meeting on the progress and 

continued funding of this research. 

FAA Response: The FAA concurs with the Committee’s recommendation and is undertaking the 

following actions to address its recommendation - The FAA will develop and provide the 

requested briefing on the progress and continued funding of fatigue research at the SAS Spring 

2021 meeting. 

Recommendation 4: The Subcommittee recommends for the FAA to restore full multi-year 

funding for the two research projects discussed above, which follow up on the effectiveness and 

utility of the FRMS/FRMP and allow the FAA to identify shortfalls and potential enhancements 

to the current flight time/duty time regulations. Furthermore, the Subcommittee recommends the 

FAA reevaluate its methodology for prioritization and funding for multi-year human subject 

research that results in a more stabilized and continuous support for those projects. 

FAA Response: The FAA concurs with the Committee’s recommendation and with the noted 

exceptions and clarifications intends to undertake the following actions to address its 

recommendation - Due to competing AVS research priorities, the fatigue research did not receive 

funding for the FY 22 AVS research portfolio. However, the project will be re-evaluated using a 

new process developed for FY 23 and weight will be given to the project as a continuing 

research project. This extra prioritization weight should allow the project to regain funding for 

the FY 23 portfolio. The lapse in FY 22 funding may be addressed if additional funding 

becomes available from the approved FY 21 Congressional appropriation. 
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Finding: Aircrew Stress Biomarker Research - The SAS REDAC received an update on 

aircrew stress biomarker research at the FAA’s Civil Aerospace Medical Institute (CAMI). The 

committee is impressed with this world-leading research effort. Objective markers for degraded 

aircrew performance and health are urgently needed to replace current subjective reporting 

methods that fail to reliably aid accident investigators in assessing human factors in accident 

causation. This ground-breaking research into gene expression and genetic-based biological 

indicators at CAMI is unique in the federal government and aims to deliver tools that can 

identify pre-accident aircrew stress states (e.g., fatigue, hypoxia, disorientation) that will 

revolutionize aircraft accident investigation. Additionally, these techniques, when validated, can 

serve as fitness-for-work assessments, giving safety and management personnel tools for real 

time risk assessment decision-making. 

Recommendation 5: The Subcommittee requests that the FAA consider the potential short- and 

long-term benefits of objective genetic-based biomarkers for aircrew stress and impaired 

performance and evaluate possible stable funding strategies to support this important and unique 

forward-looking research program. 

FAA Response: The FAA concurs with the Committee’s recommendation and is undertaking the 

following actions to address its recommendation - Leveraging the FY23 AVS research and 

development process, which focuses on 5-year planning windows within Budget Line Items 

(BLIs) oriented around Service/Office identified operational capabilities, AAM has sponsored 

the following operational capabilities and associated research objectives within the Aeromedical 

Research BLI for FY21-26: 

• Biomarker-based fatigue management system

­ Expand the current state of knowledge regarding the association between fatigue and 

performance under varying fatigue states (i.e., acute fatigue, chronic fatigue, shiftwork,

workload fatigue) 

­ Identify genetic biomarkers associated with cognitive performance under varying fatigue 

states 

­ Identify genetic biomarkers associated with inter-individual variation in tolerance and 

performance impairment from fatigue 

• Biomarkers to enhance Safety Management System with improved postmortem drug 

detection

­ Identify genetic biomarkers associated with consumption of drugs to expand drug specific

detection thresholds relative to current techniques 

­ Develop and validate genetics-based methods for detecting drug use in novel tissue 

specimens relative to current techniques. 

Finding: Ice Crystal Icing - The Subcommittee appreciates the FAA research in Ice Crystal 

Icing on High Altitude Icing on Turbine Engine Damage and Power loss. The project is 

currently funded through the 2020 fiscal year but not beyond. Further in-depth research can aid 

current rulemaking work to address this issue appropriately. 

Current funding was used for several flight campaigns however, the data analysis portion 

requires addition funding for consultants. Additionally, as many projects are put on hold during 
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the COVID-19 pandemic, funding should be available for ongoing work including additional 

testing for modeling and testing for ICI accretion behind the fan. 

Recommendation 6: The FAA should consider further funding for Ice Crystal Icing research for 

Fiscal years 2021 and 2022 and beyond as this problem has not been adequately addressed in 

certification and rulemaking. The FAA should consider additional research in the following 

fields: 

• Aerosol testing to determine how the water droplet adheres to the pollutant. 

• New engine entrants and components (e.g. wide cord fans, composites, etc.) 

FAA Response: The FAA concurs with the Committee’s recommendation and is undertaking the 

following actions to address its recommendation - For Aerosol Testing to determine how the 

water droplet adheres to the pollutant, the FAA is currently funding and in the initial stages of 

planning a FY2022 flight campaign in Asia. This flight program will be a collaborative effort 

between FAA, NASA, Honeywell, Nagoya University (Japan), with additional in-kind support 

from Boeing. This program incurred a 1–year delay until 2022, due to COVID-19, and is 

contingent on NASA’s continued support. The results of the aerosol flight campaign will be 

used to determine whether the turbine engine icing certification requirements of §33.68 as 

described in Appendix D to Part 33 are representative of expected high aerosol conditions. 

• For new engine entrants and components (e.g. wide chord fans, composites, etc.) the 

FAA has developed a Technology Plan (DOT/FAA/TC-20/34) for identifying and 

understanding the physics of ice crystal icing in turbine-engine compressor flow paths. 

This Technology Plan has been circulated internationally among research organizations, 

as an agreed list of research needs to understand and model flow path ice accretions. 

Additionally, the FAA has invested in a rotating rig compressor that can be inserted into 

simulated altitude icing wind tunnels, as the primary tool for better understanding and 

simulating ice crystal accretions within compressor flow paths. The first altitude 

operation of the rig is planned for April 2021, with follow-on testing at other test 

facilities in future years. Test planning will be guided by the FAA’s internationally 

agreed Technology Plan, and may include a large-scale rotting rig in 2024, pending the 

initial small-scale rig test. The results of the rotating rig testing will be used to develop a 

scientific theory of ice crystal icing, facilitating engine designs that are robust with 

respect to ICI, and to develop methods of compliance to §33.68 that can be applied to a 

wide range of engine designs. 

Subcommittee on Environment and Energy 

General Observations: The Subcommittee once again focused on reviewing the R&D portfolio 

for Environment and Energy that was developed based on the FY20 budget that was enacted on 

December 20, 2019 and an update on the FY21 budget. During the meeting, the Office of 

Environment and Energy (AEE) provided updates on all of the major research components of the 

portfolio. Work on programs such as the Aviation Sustainability Center of Excellence 

(ASCENT); Continuous Lower Energy, Emissions and Noise (CLEEN); Commercial Aviation 
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Alternative Fuels Initiative (CAAFI); Carbon Offsetting and Reduction System for International 

Aviation (CORSIA) and the Aviation Environmental Design Tool (AEDT) have been 

progressing. The updates highlighted accomplishments that have been realized both locally and 

on the international front directly linked to the research that has been completed since our last 

meeting. There was some discussion on how to publicize the accomplishments of the AEE 

research. 

Despite the COVID-19 concerns that we had expressed in our last report, the Subcommittee was 

very impressed with the job the leadership and staff of AEE has been doing. The presentations 

were well done and reflected impacts and or potential impacts, because of COVID-19, to the 

research that is being done and is proposed in the future. The presentations outlined a high level 

of communication between AEE staff and their partners to continue these necessary research 

efforts. The Subcommittee is also very happy to learn about the number of staff that have been 

hired to fill staff vacancies and the fact that the grant process has been improved resulting in a 

large number of grants being awarded. 

The Subcommittee believes that AEE is doing a good job and has once again presented a 

balanced portfolio. We believe that the research priorities that the Subcommittee has previously 

identified do not need to be adjusted. The Subcommittee was happy to see that a number of new 

research projects have been added to study the impacts of UAS/UAM and Supersonics. The 

Subcommittee members realize that there is still additional research required to address ongoing 

areas of concern. There was some discussion among the members on whether there are any 

research opportunities that currently exist because of the impacts that COVID 19 has had on 

aviation industry. 

The Subcommittee is comfortable that AEE, the ASCENT Center of Excellence, CLEEN 

Program, CAAFI and others efforts, as well as and their partners, including NASA, are working 

together to realistically address the potential impact that the COVID-19 pandemic could have on 

continued research efforts. This pandemic continues to have a major impact on the citizens of 

the world and the aviation industry, among others. 

Finding: Global Leadership - It is evident that the FAA AEE currently maintains a leadership 

role in ICAO CAEP and has been the driving force behind the push for data driven rule making. 

Despite the impacts of COVID 19 on aviation globally, the Subcommittee firmly believes that 

maintaining the U.S. global leadership position at ICAO CAEP is essential and advantageous to 

U.S. aviation industry. Work that has been done with ASCENT and the Volpe Center has clearly 

allowed the FAA to maintain a scientifically supported position at ICAO CAEP. The close 

collaboration with NASA at ICAO CAEP is also clearly supporting global leadership. Anything 

that jeopardizes ongoing research at AEE will impact the FAA/U.S. global leadership position at 

ICAO CAEP. 

Recommendation 1: The Subcommittee recommends the continuing strong support of all 

research efforts/programs that will allow the FAA and the U.S. to maintain its current global 

leadership position at ICAO CAEP. It is the belief of the Subcommittee that if the FAA/U.S. 
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does not maintain its leadership position at ICAO CAEP it will not be able to influence 

policy/rulemaking and this could have a significant negative impact on the U.S. aviation 

industry. 

FAA Response: The FAA concurs with the Committee’s recommendation and is undertaking the 

following actions to address it - The FAA appreciates the support of the Subcommittee for our 

ICAO CAEP activities and the importance of continued U.S. leadership therein. We concur that 

it is critical for FAA to have robust participation in the ICAO CAEP process, and we have 

allocated resources such that we can provide leadership in many of the working groups of CAEP, 

as FAA leadership is critical to securing overall U.S. objectives at ICAO. FAA prioritized 

research efforts include developing the modeling capabilities and generating the data to support 

the decision-making process within ICAO CAEP. Under the direction of FAA, much of this 

work is being done by ASCENT COE universities and the Volpe Center, in close collaboration 

with NASA and industry. We are currently working with U.S. stakeholders and the international 

community to develop noise standards for supersonic aircraft with a focus on landing and takeoff 

noise. As AEDT is the primary tool for supporting decision making related to noise at ICAO 

CAEP, we are working with the Volpe Center to enhance its capabilities to include supersonic 

aircraft. In addition to this broad effort related to supersonic aircraft, FAA is also utilizing the 

broad research portfolio of ASCENT and expertise at NASA and DOE to ensure that the 

evaluation of any long-term aspirational goal is based on robust scientific analyses that quantify 

the economic costs and potential benefits of any specific goal. Finally, we continue to advance 

work in ICAO to ensure that sustainable aviation fuels from biomass and wastes as well as lower 

carbon aviation fuels from fossil resources are appropriately credited within the ICAO Carbon 

Offsetting and Reduction System for International Aviation (CORSIA). 

Finding: Public Private Partnerships - The Subcommittee wishes to acknowledge and support 

the fact that the Office of Environment and Energy (AEE) have proven over decades to be very 

good stewards of taxpayer money. The leadership team at AEE has used their budgeted amounts 

to conduct and coordinate the research necessary to produce informed, data driven policies, 

facilitate technological advances in the aviation industry, and produced models and data that 

have positioned the U.S. as both a State leader at ICAO CAEP and on the global aviation stage. 

The execution of this research portfolio has been accomplished by working collaboratively with 

private industry, major universities through the ASCENT Center of Excellence, other Federal 

Departments and Foreign Governments. Three quarters of Environment and Energy research 

funds generate 100% plus cost matching from non-federal partners (CLEEN, CAAFI, and 

ASCENT). This leverages scarce FAA R&D funds to accomplish significant advances and 

improvements. In addition, we believe that government funding has been used and executed 

effectively to lower the risk of new and emerging technologies such that they can be adopted by 

industry. The benefits of these partnerships has clearly been proven over time and is very 

apparent in most of the current projects. The maturation of new technologies has delivered 

improved environmental performance and has enabled aviation system growth and associated 

positive economic impacts. 

Recommendation 2: The Subcommittee continues to endorse Public Private Partnerships like 

the CLEEN, CAAFI and ASCENT programs to leverage resources and recommends that FAA 

should continue to allocate robust funding for these programs.
12

FAA Response: The FAA concurs with the Committee’s finding and recommendation and is 

undertaking the following actions to address it - The FAA is maximizing the impact of taxpayer 

dollars by partnering with industry, academia and other governments. The vast majority of the 

Environment and Energy R&D program has been leveraging resources from the private sector 

via public-private partnerships. CLEEN, CAAFI and ASCENT have all been successful because 

of their strong engagement with industry. Each of these programs have had strong partnerships 

with, and support from, industry for over a decade. The FAA is taking action to initiate the third 

phase of CLEEN, which will ensure continuation this model of partnership of public-private 

partnership on aircraft technology development through 2025. CLEEN Phase III is expected to 

be kicked off in the coming months. We also appreciate the recognition of our close partnership 

with NASA and its value. Our inter-agency collaboration also extends to close collaboration 

with a number of Federal Agencies in topics related to jet fuel. Finally, we are also collaborating 

with a number of international research institutions through CAAFI and the ASCENT COE. We 

have worked diligently to develop all of these partnerships over many years and intend to 

continue to do so going forward. 

Finding: Sustainable Aviation Fuels (SAFs) - Significant gains have been realized in the 

Alternative Jet Fuel (AJF) Program (including efforts in the Commercial Aviation Alternative 

Fuels Initiative (CAAFI), CLEEN and ASCENT). Sustainable Aviation fuels (SAFs) are a 

critical component of the industry’s emissions reduction strategy and must be developed if 

industry is to get to their carbon neutral growth goals after 2020 and their emissions reduction 

goals in 2050. This research has helped with the creation of a number of companies that have 

the potential to benefit the rural economies of several states and the U.S. Aviation industry. 

More than 3 million gallons of SAF was used in the first half of 2020 and expectations are 

positive that there will be a significant increase in consumption as production is increased. 

Recent support from a number of agencies, including the DOE will support SAF production. 

There are efforts to ensure that alternative jet fuels are in CORSIA through ICAO CAEP. The 

Subcommittee members were very pleased to see that funding in this area has been restored in 

the President’s budget for FAA AEE and they applaud the FAA leadership for their foresight on 

this matter as they are making it once again a vital part of their overall investment portfolio 

Recommendation 3: It is still the position of this Subcommittee that the work on Sustainable 

Aviation Fuels is critical to the U.S. industry and the FAA should maintain a leadership role in 

the development of SAFs to ensure that the rules to be considered will be beneficial to the U.S. 

industry. Since the maturation of the Alternative Jet Fuel program will be a major environmental 

benefit for the public, will create a new industry within the U.S. that benefits rural America, and 

will benefit the U.S. aviation industry, we strongly recommend that the FAA AEE continues to 

allocate funds for the continuation of research on SAFs. 

FAA Response: The FAA concurs with the Committee’s finding and recommendation and is 

undertaking the following actions to address it - The FAA appreciates the Committee’s inputs on 

the importance of sustainable aviation fuels to industry. This industry pull is driving our 

continued efforts on jet fuel research. We are pleased to see the increasing uptake of sustainable 

aviation fuels by industry with more than 3 million gallons being uplifted in the first half of 
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2020. This is especially impressive when one considers the impacts of COVID-19 on the 

aviation industry. Our efforts ensure that these fuels are safe for use and the results of our efforts 

are reducing the time and costs to get new fuels approved. Continued approvals for new fuels 

ensure that the aviation industry has access to a broad range of fuel options, and having more 

fuel options should reduce the cost of fuel production, enable greater environmental benefits, and 

allow for greater blend levels. We are very pleased that eight different fuel types have been 

approved for use in civil aviation by ASTM International. Our research efforts also ensure that a 

wide range of aviation fuels can receive credit under the ICAO Carbon Offsetting and Reduction 

Scheme for International Aviation (CORSIA). This is critical to not only allowing airlines 

additional means to meet their international commitments under CORSIA, but also to gain 

international agreement on what is meant by sustainability. Our research efforts are also 

supporting techno-economic analysis to understand how to reduce fuel costs and producing 

scenarios of future production to inform decision making and planning by both governments and 

industry. The research program is also providing substantial support to CAAFI, which is 

essential for coordinating efforts across the aviation industry. AEE continues to coordinate with 

other federal agencies to make sustainable aviation fuels a focus area of the overall federal effort 

to stimulate the development of the Bioeconomy and support rural development. This has 

resulted in the formation of a new interagency working group focused on SAF under the auspices 

of the multi-agency Biomass Research and Development Board. 

Finding: Noise Research - Aviation noise continues to be an issue that requires ongoing 

research. The Subcommittee realizes that there is much research that is still necessary to address 

the ongoing topic of aviation noise. AEE has a number of research projects that are looking at 

the impacts of noise on children’s learning, sleep impacts, community annoyance and 

cardiovascular health. AEE is looking at the certification requirements for supersonic aircraft as 

well as UAS that are larger than 55 pounds. AEE is also examining how to reduce the noise 

from commercial aircraft and helicopters through changes in operational procedures. There are a 

number of new research projects that have been added to address issues related to new entrants 

into the aviation system. There also have been significant upgrades made to the Aviation 

Environmental Design Tool (AEDT). FAA has also launched an initiative to partner with 

airports to gather more noise data resulting from noise complaints. Finally, AEE is working with 

industry to accelerate the development of technologies that reduce noise through the CLEEN 

Program. 

Recommendation 4: The Subcommittee strongly supports the prioritization of the noise research 

that will support informed decision-making, the introduction of new entrants to the National Air 

Space, and enable NextGen deployment. 

FAA Response: The FAA concurs with the Committee’s finding and recommendation and is 

undertaking the following actions to address it - Noise continues to pose a challenge to the 

growth of aviation and could impact the introduction of new vehicle types to the National 

Airspace System (NAS). We have been working for many years to better understand the issues 

associated with noise from subsonic airplanes and helicopters and to identify solutions that could 

help address noise concerns. For example, we are continuing to explore operational procedure

concepts and engagement approaches that could help identify ways to mitigate noise issues while 

also improving the Aviation Environmental Design Tool (AEDT) to ensure it can quantify 
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aircraft noise at further distances from airports, where some communities are expressing 

concerns. Noise reduction from gas turbine powered fixed wing aircraft is an area of emphasis 

for the third phase of the CLEEN Program, which will start in 2020 and is included in the FY 

2021 President budget request. We are also working in close collaboration with NASA to 

address noise from Subsonic and Supersonic aircraft, helicopters, UAS, and UAM. We are also 

engaged within FAA and with industry to identify opportunities to conduct noise measurements 

of UAS and UAM to inform future decisions. Finally, we have stood up several new ASCENT 

Center of Excellence (COE) projects in the last year to address noise. These will help us better 

understand noise generation from a wide range of vehicle types and should help the FAA and 

aviation industry develop cost-effective solutions to reduce the impacts of noise on communities. 

Subcommittee on NAS Operations 

Finding: Research Landscape - The Subcommittee received a briefing describing the FAA’s 

progress in developing and exploiting its Research Landscape for the National Airspace System. 

The briefing included an overview of the purpose and framework for the Landscape, and a view 

ahead to next steps for the effort. 

The Subcommittee appreciates the utility of defining research Drivers and mapping them to the 

various RE&D activities within the FAA. The organization of the Landscape into four major 

Driver categories (Advances in New Vehicles / New Missions; Advances in Technology and 

Materials; Advances in Data and Processing Power; System Wide Advancements / 

Improvements) is helpful toward understanding how the broad range of RE&D programs span 

the space of work required to progress beyond NextGen. Some challenges in the roll-out of this 

process were identified, including the need to better socialize the various drivers so that program 

managers understood where their programs would fit within the Landscape, and some practical 

matters such as requiring the ability to allow program managers to map their work to more than 

one driver. We anticipate that those challenges will be easily addressed in the near future. At 

this time, however, the connection between the Research Landscape and the FAA’s research 

planning process has not been clearly articulated. The Subcommittee identified an opportunity to 

more explicitly connect the Research Landscape to the FAA’s RE&D planning and prioritization 

efforts. 

Recommendation 1: The NAS Operations Subcommittee recommends that the FAA more 

clearly define how the results of the Landscape effort will inform RE&D prioritization, and 

subsequently report out periodically to the REDAC Subcommittees on the prioritization process. 

By making a connection between Drivers and priorities, we anticipate there will be more utility 

extracted from the Landscape process beyond its current value in communicating Driver-to 

Research mappings. Ideally, the Subcommittees would be provided with regular updates on the 

connections between Drivers, RE&D programs, and their priorities, to build a more holistic 

understanding of the FAA’s research portfolio. 

Consequences: A failure to explicitly connect the Research Landscape to RE&D program 

priorities would limit the utility of the Landscape effort. Lacking that connection would 

represent a missed opportunity to make full use of the efforts expended in building and 

maintaining the Landscape. 
15

FAA Response: The FAA concurs with the Committee’s finding and recommendation and is 

undertaking the following actions to address its recommendation - The Landscape effort is 

intended to be an industry outreach tool to inform the FAA research community and the research 

portfolio about advances in aviation and aerospace. This key input ensures that the FAA 

research portfolio remains industry-driven and that the research enables the safe implementation 

of innovation. Identification and collaborative understanding of the Landscape Drivers, permits 

the FAA to identify research opportunities and gaps to align and prioritize portfolio investments 

to industry objectives and trends. The Landscape effort will highlight if new or additional 

research areas are needed or if funding is adequate. The FAA will more clearly define the 

methodology for prioritization during the Full Committee – Winter/Spring in April 2021. 

Finding: Resilient autonomy in the future NAS – The Subcommittee received briefings on the 

FAA 2035 Vision and related development of a 2045 Vision by NASA. These invoke a 

significantly higher degree of autonomy than today’s NAS, with machine learning (ML) and 

artificial intelligence (AI) supporting a dense operations environment comprised of diverse 

vehicles and operating entities. These visions allude to the need for operations-recovery 

constructs and infrastructure resiliency when off-nominal conditions occur. The Subcommittee 

notes, however, that responding to novel, or previously unobserved situations (and recognizing 

precursors to these) is particularly challenging for ML/AI technology. 

Recommendation 2: Development of strategies for effectively responding-to and recovering 

from significant, off-nominal scenarios should be a priority in these future NAS visions. The 

off-nominal scenarios encompass both unplanned operational events as well as system failures. 

In system failures, the likelihood that significantly-more-intense operational responsibilities will 

need to shift back temporarily to the human work force in a graceful manner (airline, air-traffic 

control and flow-management) during off-nominal situations should be considered. In addition, 

historical data on these autonomous systems performance and behavior does not exist, and thus a 

prognostic analytical approach is needed to determine the system health as well as assist in 

standards development and certification processes. Furthermore, the autonomous systems will 

need to co-exist and be integrated into the traditional human centric systems. The Subcommittee 

recommends that future versions of these FAA and NASA visions, and their related RE&D 

efforts, explicitly address strategies for off-nominal event management, recovery, and graceful 

system degradation, and that these be briefed to the Subcommittee when appropriate. 

Consequences: If research on autonomous system resilience is not explicitly included in the 

future NAS vision and its associated RE&D programs, there is a risk that additional costs will be 

incurred later in the development process to achieve the high levels of safety and efficiency that 

are required. 

FAA Response: The FAA concurs with the Committee’s recommendation(s) and with the noted 

exceptions and clarifications intends to undertake the following actions to address its 

recommendation(s) - This concurrence is with respect to its general characteristics as outlined in 

the recommendation, which are and always will be part of our research. The exception is related 

to the finding and therefore the application of the recommendation to the specific case in the 

finding. The Committee has included aspects of the FAA’s vision and NASA’s vision without 

differentiation. The Committee’s recommendation includes assumptions on the use of AI and 
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ML in a tactical mode, which is part of the NASA Vision, but not currently a component in the 

nearer term FAA vision. The FAA has ongoing activities for the use and qualification of AI and 

ML for ATM in an advisory mode with NASA. 

Finding: Flight Deck Data Exchange Requirements Program Coordination - The 

Subcommittee received separate briefings on A11.r Flight Deck Data Exchange Requirements 

and on Aircraft Systems Information Security Protection (ASISP) research. These presentations 

described the benefits, initial accomplishments, and anticipated future research in each program. 

Both of these efforts are targeted at identifying and mitigating potential cyber vulnerabilities in 

aircraft systems including air-ground information exchange. An important part of the cyber 

analysis process is developing a methodology that is both effective and vetted across multiple 

stakeholders including the FAA and other government agencies, and industry spanning airframe 

manufacturers, avionics, ground systems, and data communications systems. The ASISP 

program has built a strong cyber Safety Risk Assessment (SRA) methodology that has been 

closely coordinated with industry and government stakeholders including the Cyber Safety 

Commercial Aviation Team (CS CAT) and broader constituencies such as the tri-agency 

Aviation Cyber Initiative (ACI) and the international Aviation Information Sharing and Analysis 

Center (A-ISAC). ASISP has successfully conducted several cyber system analyses on critical 

components such as the Flight Management System. 

In contrast, the cyber analysis process currently being used in A11.r was not explained directly, 

and it was apparent that this effort is not closely coordinated with or leveraging the 

methodologies and accomplishments of the ASISP program. Some efforts, such as analysis of 

Aircraft Information Displays and Flight Management Systems, appear to be duplicative or 

overlapping with ASISP. 

Recommendation 3: The FAA should ensure that the A11.r research effort is making full use of 

and closely coordinating with the ASISP program. Findings and methods used in ASISP should 

be informing the methods used in A11.r, and likewise results from A11.r should be coordinated 

with ASISP and the broader ACI and A-ISAC communities. 

Consequences: A failure to closely coordinate the activities under A11.r and ASISP risks 

duplicative efforts and reduced progress in the important work required to ensure aviation cyber 

security. Especially given the limited RE&D budgets available for cyber work, it is important to 

ensure all efforts are coordinated and augment progress. 

FAA Response: The FAA concurs with the Committee’s recommendation(s) and with the noted 

exceptions and clarifications intends to undertake the following actions to address its 

recommendation(s) - Advancement in aircraft connectivity and onboard avionics are enabling 

Air Traffic Management (ATM) automation and Air Traffic Controller (ATC) to exchange ATM 

related data (both situational awareness and safety critical data) with the aircraft. The Flight 

Deck Data Exchange Requirements (FD DER) project (A11.r) conducts research and investigates 

cybersecurity concerns around current and emerging technologies enabling connected aircraft 

concept in order to enable the enhanced flight deck data exchange to support ATM functions. 

As part of investigating the data exchanges between the aircraft and ground automation systems 

to support ATM functions, the FD DER project identified representative emerging architectures 
17

and an initial cybersecurity analysis was performed for Electronic Flight Bag (EFB), Aircraft 

Interface Device (AID), and commercial Internet Protocol (IP) based datalink. These analyses 

were conducted leveraging security assessment methodology that adheres to the standard 

guidance provided by Airworthiness Security Process Specification (RTCA DO-326A) and 

Airworthiness Security Methods and Considerations (RTCA DO-356A) with components of 

Common Vulnerability Scoring System (CVSS v3.0). The methodology has been further 

customized by a leading avionics vendor who applied this tailored methodology in multiple 

certifications for aircraft systems and components, and has been vetted by the FAA, European 

Union Aviation Safety Agency (EASA), and National Civil Aviation Agency of Brazil (ANAC). 

While the interest of the ASISP project is on cybersecurity of avionics and its interfaces, the FD 

DER project focuses on protecting data exchanges that are issued by the ATM systems and 

delivered to avionic components onboard the aircraft. This research project identifies threats, 

vulnerabilities, and associated mitigations to allow for secure data exchanges originated by NAS 

ATM systems that goes through EFB, AID, and commercial IP based datalink supporting 

connected aircraft operations. The outcomes will provide security considerations to inform 

future development of ATM concept and applications that involve information exchanges with 

connected aircraft. The FD DER team will coordinate and share the results of research to allow 

for cross-collaboration between these programs to complement one another, and provide the 

aviation community with a comprehensive cybersecurity considerations and support 

advancement of the connected aircraft technology and applications.