Safety Recommendation A-18-031

From the Aviation Investigation Report AIR-25-04 “In-Flight Separation of Left Mid Exit Door Plug, Alaska Airlines Flight 1282, Boeing 737-9, N704AL, Portland, Oregon, January 5, 2024” published on July 10, 2025:

2.6.3.2 Need for 25-Hour Cockpit Voice Recorder Installations and Retrofits

In addition, the NTSB has long advocated for requirements for 25-hour CVRs, which would mitigate the risk of a CVR recording being overwritten. In October 2018, we issued Safety Recommendations A-18-30 and -31 based on investigations lacking access to relevant CVR data (NTSB 2018). These investigations included a July 2017 taxiway overflight incident in San Francisco, California, which had significant safety issues. Also, following the previously referenced runway incursion and overflight incident that occurred in Austin, Texas, on February 4, 2023, we reiterated Safety Recommendation A 18 30 and superseded A-18-31 with A-24-9 (NTSB 2024).

The safety recommendations asked the FAA to take the following actions:

Require all newly manufactured airplanes that must have a CVR be fitted with a CVR capable of recording the last 25 hours of audio. (A-18-30) Require retrofit of all CVRs on all airplanes required to carry both a CVR and a flight data recorder with a CVR capable of recording the last 25 hours of audio. (A-24-9)

In December 2023, the FAA addressed Safety Recommendation A-18-30 by publishing a notice of proposed rulemaking (NPRM) proposing that newly manufactured aircraft be equipped with CVRs capable of recording 25 hours of data. If issued, a final rule based on the NPRM will likely satisfy this recommendation, which is currently classified Open—Acceptable Response. However, ee do not fully support the NPRM because it did not propose a similar requirement to retrofit existing airplanes required to carry a CVR and an FDR, as discussed in Safety Recommendation A-24-9. Accordingly, this recommendation is currently classified Open—Unacceptable Response.

On May 16, 2024, the FAA Reauthorization Act of 2024 became law. The act required 25-hour CVRs for aircraft operated under Part 121, other transport category airplanes that were type certificated with a seating capacity of 30 or more passengers, and cargo derivatives of such airplanes that are operated under other regulations. The act specified that newly manufactured aircraft would be equipped with 25-hour CVRs starting 1 year after the date of the act. Also, the act specified that affected operators were to retrofit their aircraft with a 25-hour CVR no later than 6 years after the date of the act.

In addition, the act required the FAA, within 3 years of the date of the act, to issue a final rule to update applicable regulations to conform to the CVR retrofit requirement for existing aircraft.

The airplane involved in this accident would not be subject to the proposed rulemaking announced by the FAA in December 2023 but would be subject to the 6 year retrofit requirement in the FAA Reauthorization Act of 2024. Although the statutory requirement for 25-hour CVRs on newly manufactured airplanes is in effect, the FAA has not yet issued a final rule to incorporate this provision into the regulations. Since the original issuance of our CVR recommendations in 2018, more than 20 of our investigations (including this investigation) have been negatively affected by overwritten CVR data (see table 4).

As the number of events listed in table 4 shows, the potential for data to be overwritten on a 2-hour recorder persists. Thus, the NTSB concludes that the circumstances of this accident and others show that CVRs with a 25-hour recording capability are necessary because valuable information continues to be overwritten on CVRs that are designed to record only 2 hours of audio data. Therefore, the NTSB reiterates Safety Recommendation A-24-9 to the FAA.

Further, the NTSB notes that nearly 18 months have passed since the FAA released the NPRM to require 25-hour CVRs on newly manufactured airplanes, and, as stated previously, although the statutory requirement is in place, the FAA has not yet issued a final rule to incorporate the provision into regulations. Therefore, the NTSB reiterates Safety Recommendation A-18-30.

This letter provides information about the National Transportation Safety Board’s (NTSB) May 29, 2024, report Runway Incursion and Rejected Takeoff, American Airlines Flight 106, Boeing 777-200, N754AN, and Delta Air Lines Flight 1943, Boeing 737-900, N914DU (NTSB/AIR-24-01). The details of this accident investigation and the resulting safety recommendations may be found in the attached report, which can also be accessed at http://www.ntsb.gov.

As a result of this investigation, we identified the following safety issues: • the need for a procedural crosscheck that requires flight crews to verbalize the number of a runway they are about to cross as indicated by runway signs; • the lack of flight deck technology to detect potential traffic conflicts on a taxiway or runway surface; • the need for additional risk mitigation strategies to reduce the likelihood that flight crew surface navigation errors result in runway incursions; and • the need for cockpit voice recorders with a 25-hour recording capability. Accordingly, the NTSB makes the following safety recommendations to the FAA.

Additional information regarding these recommendations can be found in the noted sections of the report. • Encourage Title 14 Code of Federal Regulations Part 91K, 135, and 121 operators to incorporate into their standard operating procedures a procedural crosscheck that requires flight crews to verbalize the number of a runway they are about to cross, as indicated by runway signs, unless an installed automated system already provides an aural advisory. (A 24 2) (See section 2.3.1.)

• Encourage Title 14 Code of Federal Regulations Part 121 operators to use their safety management system to identify flight crew surface navigation errors resulting from the performance of concurrent tasks during taxi and develop and implement effective risk mitigation strategies considering human factors principles. (A-24-3) (See

The National Transportation Safety Board (NTSB) has reviewed the Federal Aviation Administration’s (FAA) notice of proposed rulemaking (NPRM) titled “25 Hour Cockpit Voice Recorder (CVR) Requirement, New Aircraft Production,” published at 88 Federal Register 84090 on December 4, 2023. The NTSB notes the FAA is proposing to require the installation of 25-hour duration CVRs on only newly manufactured aircraft that require a CVR operating under Title 14 Code of Federal Regulations Parts 91, 121, 125, and 135.

For the reasons provided in this response, we do not fully support the NPRM because it does not propose a similar requirement to retrofit existing airplanes required to carry a CVR and a flight data recorder (FDR).

In 2018, the NTSB issued the following two recommendations to the FAA: Require all newly manufactured airplanes that must have a cockpit voice recorder (CVR) be fitted with a CVR capable of recording the last 25 hours of audio. (A-18-30)

By January 1, 2024, require retrofit of all cockpit voice recorders (CVR) on all airplanes required to carry both a CVR and a flight data recorder with a CVR capable of recording the last 25 hours of audio. (A-18-31)

As noted in the NPRM, these recommendations were issued after an incident in 2017 when an Air Canada Airbus A320 lined up to land on a taxiway occupied by several aircraft. The flight crew of the Airbus A320 descended below 100 feet above ground level before starting to climb. The CVR data were overwritten before Air Canada officials learned of the severity of the incident.

Although this incident prompted Safety Recommendations A-18-30 and A-18-31, the NTSB also identified 33 other events where the CVR data were overwritten because there was a delay between an event and the flight crew recognizing that event to be a serious incident or accident or the flight continued to operate for more than 2 hours after the event took place.

Since Safety Recommendations A-18-30 and A-18-31 were issued, at least 14 additional investigations have been hampered by the lack of CVR data that were overwritten, including 7 serious runway incursions that occurred in 2023 and a rapid decompression that occurred on an Alaska Airlines 737-9 MAX flight on January 5, 2024 (see table). In our 2018 report, the NTSB noted that CVRs are among the most valuable tools for accident investigation because they provide contemporaneous information on flight crew intentions and coordination as well other factors, such as procedural compliance, workload, fatigue, and situational awareness.

We note that you have initiated rulemaking to require all newly manufactured airplanes that must have a CVR to be fitted with one capable of recording for 25 hours. We also note that you have asked an ARC to review and make recommendations to the FAA about these and other related NTSB safety recommendations.

We believe the rulemaking that you described is responsive to Safety Recommendation A-18-30; however, we are concerned that the rule would only apply to newly manufactured airplanes, and not the retrofit of all airplanes required to carry a CVR and FDR, as recommended in Safety Recommendation A-18-31.

Pending our review of the proposed rule, Safety Recommendation A-18-30 is classified Open—Acceptable Response. Pending our review of a plan for developing a similar requirement for existing airplanes, Safety Recommendation A-18-31 remains classified OPEN-- UNACCEPTABLE RESPONSE.

-From Billy Nolen, Acting Administrator: The Federal Aviation Administration (FAA) initiated a rulemaking (2120-AL92) that would propose newly-manufactured aircraft to be equipped with CVRs capable of recording for 25 hours, along with operational rules that would require using those CVRs when installed. Furthermore, the FAA is launching an Aviation Rulemaking Committee (ARC) that will provide a forum for the U.S. aviation community to discuss, prioritize, and provide recommendations to the FAA concerning requirements for the installation of existing, new, and upgraded investigative technologies that affect applicable airworthiness standards and operating rules.

The ARC will also specifically consider the Board’s safety recommendations as part of its discussions.

I will keep the Board informed of the FAA’s progress on Safety Recommendations A-18-30 and -31 and provide an update by June 30, 2024.

We note that you submitted a rulemaking project for fiscal year (FY) 2020 to determine the feasibility of satisfying Safety Recommendation A-18-30; however, it was not accepted by the FAA Rulemaking Council. Although you reported plans to resubmit the rulemaking project in FY 2023, your staff reported that it has not yet been submitted or approved. Additionally, the proposed rulemaking project would only address newly manufactured airplanes, and not the retrofit of all airplanes required to carry a CVR and FDR, as recommended in Safety Recommendation A-18-31.

CVRs provide unique information with which the NTSB can conduct more thorough investigations to more effectively target safety recommendations. However, we continue to investigate accidents and incidents where valuable CVR data were overwritten and unavailable for our safety investigations. Lacking these data means that an investigation may not identify issues that played a role in the event, which could result in a similar—or worse—occurrence in the future. Enclosed is a table showing 12 NTSB investigations of accidents or incidents that occurred since 2018—including 4 that occurred at the beginning of this year—in which CVR data were overwritten before investigators could access it.

These recommendations are almost 5 years old and rulemaking to address them has not yet been submitted or approved, and those are only the first steps in the rulemaking process. If approved, the FAA will still need to draft a notice of proposed rulemaking, respond to comments, and publish a final rule. We urge the FAA to submit and approve this rulemaking project without any additional delays. Pending our receipt and review of a plan for implementing these improvements, Safety Recommendations A-18-30 and -31 are classified OPEN--UNACCEPTABLE RESPONSE.

From Billy Nolan, Acting Administrator, Federal Aviation Administration: In our previous response, the Federal Aviation Administration (FAA) noted that it had submitted a rulemaking project for Fiscal Year (FY) 2020 to determine the feasibility of requiring all newly manufactured airplanes, which must have a CVR, to be fitted with a CVR capable of recording the last 25 hours of audio. However, this project was not accepted by the FAA Rulemaking Management Council due to competing priorities and resources. We are currently reassessing the scope of this project and plan to resubmit it for FY 2023 approval to address the intent of these safety recommendations.

I will keep the Board informed of the FAA’s progress on Safety Recommendations A-18-30 and -31 and provide an update by August 31, 2023.

We note that a rulemaking project was submitted for fiscal year (FY) 2020 to determine the feasibility of satisfying these recommendations. Although we are concerned that you did not discuss the status of this rulemaking project—which we learned about in FY 2021—in your letter, we believe this is a necessary first step to responding to these recommendations. Pending our receipt and review of your assessment, and a plan for implementing these improvements, Safety Recommendations A-18-30 and -31 remain classified OPEN-- ACCEPTABLE RESPONSE.

-From Steve Dickson, Administrator: As we reported in our letter dated December 12, 2018, the Federal Aviation Administration (FAA) was looking into whether rulemaking efforts to implement these recommendations would likely meet cost-benefit guidelines. The FAA has submitted a rulemaking project for Fiscal Year 2020 to determine the feasibility of requiring CVRs to record at least the last 25 hours of audio on both newly-manufactured airplanes requiring a CVR, and all airplanes required to carry both a CVR and flight data recorder.

I will keep the Board informed of the FAA’s progress on this issue and anticipate providing an update by September 30, 2021.

We note that you are evaluating the feasibility of implementing these recommendations and assessing whether a requirement to retrofit existing airplanes, as recommended in A-18-31, would meet the Office of Management and Budget’s cost-benefit guidelines. Pending our receipt and review of your assessment, and a plan for implementing these improvements, Safety Recommendations A-18-30 and -31 are classified OPEN--ACCEPTABLE RESPONSE.

-From Daniel K. Elwell, Acting Administrator: The Federal Aviation Administration (FAA) understands and shares the concerns expressed by the Board regarding the availability of relevant CYR data in their safety investigations of events. We recognize CYRs as an important investigation tool and understand the link between successful investigations and improving future safety. We will evaluate the feasibility of these safety recommendations and will assess whether rulemaking efforts to implement them, particularly safety recommendation A-18-31 addressing retrofit, are likely to meet Office of Management and Budget cost-benefit guidelines.

I will keep the Board informed of the FAA's progress on this issue and anticipate providing an update by December 2019.

On October 2, 2018, the NTSB adopted a safety recommendation report, Extended Duration Cockpit Voice Recorders (ASR-18-04). Our analysis and the resulting two safety recommendations to the FAA may be found in the attached report, which can also be accessed at http://www.ntsb.gov.

The NTSB is vitally interested in these recommendations because they are designed to prevent accidents and save lives. We would appreciate a response within 90 days, detailing the actions you have taken or intend to take to implement the recommendations. When replying, please refer to the safety recommendations by number. We encourage you to submit your response to correspondence@ntsb.gov. If it exceeds 20 megabytes, including attachments, please e-mail us at the same address for instructions. Please do not submit both an electronic copy and a hard copy of the same response.