Safety Recommendation A-06-021

From the Aviation Investigation Report AIR-26-02, “Midair Collision over the Potomac River PSA Airlines Flight 5342, Mitsubishi Heavy Industries (MHI) RJ Aviation CL-600-2C10 (CRJ700), and US Army Priority Air Transport Flight 25, Sikorsky UH-60L Washington, DC January 29, 2025”

1.15.3 ADS-B The NTSB also has a long history of supporting the use of technologies, such as ADS-B, that provide identification and location information for aircraft due to the ability of these technologies to improve safety. Between 2006 and 2007, we recommended requirements for equipment that could provide increased aircraft identification, location, and communication capabilities for aircraft operations in the Gulf of America and remote areas of Hawaii and Alaska, with the intent of enhancing flight location, collision avoidance, and weather information services for these operations (see Safety Recommendations A-06-21 and -22, and A-07-025 and -26; NTSB, 2006; NTSB, 2007a).

Following the 2006 midair collision involving a business jet and a transport category airplane over Brazil that claimed 154 lives, we recommended requirements for equipment that could provide pilots with enhanced alerts regarding the status of transponder and traffic collision avoidance capabilities (Safety Recommendations A 07-35 through -37; NTSB, 2007b).

Following the 2007 fatal midair collision of two news-gathering helicopters over Phoenix, Arizona, the NTSB sought to enhance the traffic-avoidance logic for helicopters’ onboard equipment by recommending the development of standards and requirements for the incorporation of specific criteria for the types of maneuvers and environments unique to helicopters (Safety Recommendations A 09 4 and -5, superseded by Safety Recommendations A 10 127 and -128; NTSB 2009; NTSB, 2010).

In an October 2007 notice of proposed rulemaking to require ADS B Out, the FAA stated that it did not plan to also require ADS-B In capability because ADS-B In “has not been identified as a requirement for maintaining the safety and efficiency of NAS operations.” In a letter dated February 14, 2008, in response to this notice of proposed rulemaking, the NTSB expressed our belief that this assessment was incorrect and stated that equipping aircraft with ADS-B In capability would “provide an immediate and substantial contribution to safety,” especially near airports.

The NTSB further stated in our response to the FAA’s proposed rule that “the FAA's failure to expedite the adoption of full ADS-B capability (both ADS-B In and ADS-B Out) would be unfortunate and would result in missing or unnecessarily delaying an opportunity to remedy a serious and notorious safety issue” (NTSB, 2008).

The FAA Modernization and Reform Act of 2012 required the FAA to identify the type of avionics required for all classes of airspace. It also specifically required the FAA to initiate rulemaking to require aircraft operating in capacity-constrained airspace, at capacity-constrained airports, or in “any other airspace deemed appropriate by the administrator” be equipped with ADS-B In technology by 2020. An aviation rulemaking committee chartered in April 2012 recommended that the FAA focus on the development of key ADS-B In applications, including airborne traffic awareness systems, that would provide benefits to operators.

In 2014, the FAA developed a rulemaking action plan to issue a notice of proposed rulemaking by 2018 and a final rule in 2022.

In 2014, an RTCA committee chartered by the FAA completed the development of standards for ADS-B-supported aircraft surveillance applications, DO-317B (RTCA, 2014). However, the FAA Reauthorization Act of 2018 repealed the requirement that the FAA initiate rulemaking to require ADS-B In technology and instead directed the FAA to ensure that any regulations resulting from that rulemaking had no effect. Because the FAA had not yet issued any regulations, no action was required to change any regulations.

In May 2021, the NTSB issued several safety recommendations (A-21-15 through -17) regarding ADS B following the investigation into a midair collision between two air tour airplanes in Ketchikan, Alaska, in 2019 (NTSB, 2021a). Safety Recommendation A 21-15 asked the FAA to identify areas with a high concentration of air tour traffic and to require that 14 CFR Parts 91 and 135 air tour operators who operate within those areas be equipped with an ADS-B Out- and In-supported traffic advisory system that includes visual and aural alerts.

Safety Recommendation A-21-16 asked that the FAA require that all non-air tour aircraft operating within the airspace identified as a high traffic tour area in Safety Recommendation A-21-15 be equipped with ADS-B Out. Safety Recommendation A-21-17 asked that the FAA require the installation of ADS-B Out and In supported airborne traffic advisory systems that include aural alerting functions in all aircraft conducting operations under 14 CFR Part 135.

In a July 2021 response, the FAA requested a meeting with NTSB staff to further clarify the intent of the recommendations. However, as noted in NTSB correspondence dated February 4, 2022, when the NTSB attempted to schedule this meeting, FAA staff stated that a meeting was no longer necessary. In May 2022, the NTSB reiterated Safety Recommendation A-21-15 in our report on the fatal helicopter air tour accident that occurred in Kekaha, Hawaii, in December 2019 (NTSB, 2022).

In correspondence dated June 26, 2023, the FAA stated that its Air Traffic and Aviation Safety Organizations met to discuss the NTSB recommendations and determined that the agency’s current ADS-B requirements adequately addressed the needs of aviation safety and it would not pursue additional requirements. The FAA stated that its current guidance and requirements were sufficient to meet the intent of the recommendations. In addition, the FAA stated that the previously requested meeting with NTSB staff was no longer needed.

In an October 24, 2023, follow-up letter regarding Safety Recommendation A 21-17, the NTSB emphasized that the absence of an ADS-B In requirement for Part 135 passenger-carrying operations fails to take advantage of the demonstrated safety benefit of ADS-B In traffic awareness and alerting and is inconsistent with the “appropriate level of public safety” the FAA itself expects for operations in which passengers bear no responsibility for the aircraft’s operation (NTSB, 2023).

In its most recent response to Recommendation A-21-15, on November 6, 2024, the FAA repeated that current ADS-B requirements continue to adequately address the needs of aviation safety and that it would not pursue additional ADS B operator requirements at this time (FAA, 2024f). During the investigative hearing for the DCA midair collision, however, the FAA ATO’s acting deputy COO stated that the agency supported requiring newly manufactured aircraft in the United States be equipped with ADS-B In. He also stated that the agency supported requiring the installation and operation of ADS-B In for aircraft operating in airspace where they are required to transmit ADS B Out.

The National Transportation Safety Board (NTSB) has reviewed the Federal Aviation Administration’s (FAA) notice of proposed rulemaking (NPRM) titled, “Remote Identification of Unmanned Aircraft Systems,” which was published at 84 Federal Register 72438 on December 31, 2019. We welcome the opportunity to provide comments on this NPRM, which the FAA has identified as an important step in safely integrating unmanned aircraft (or drones, as defined in the NPRM) into the national airspace system (NAS).

The FAA stated that remote identification (remote ID) for unmanned aircraft systems (UAS), which includes location information for both the unmanned aircraft and the ground control station, is a necessary milestone for supporting expanded operations, such as those involving cargo delivery, flights over people, and flights beyond visual line of sight. The NTSB has a long history (dating back to 1969) of supporting the use of technologies that provide certain identification and location information for manned aircraft, based on the ability of these technologies to improve aviation safety.

Over the past few decades, we have issued numerous safety recommendations for the use of technologies to enable pilots, air traffic controllers, and other personnel (such as operators’ flight-followers) to maintain awareness of aircraft location, both in the NAS and in proximity to other aircraft. Thus, in the context of aviation safety, we support the general concept of remote ID for UAS. We offer our comments on the NPRM as a general concurrence with the concept as a milestone for enabling the safe integration of a wide variety of UAS operations into the NAS by supporting enhanced aeronautical services, such as collision avoidance and air traffic management.

For example, between 2006 and 2007, we recommended requirements for equipment that could provide increased aircraft identification, location, and communication capabilities for manned aircraft operations in the Gulf of Mexico and remote areas of Hawaii and Alaska, with the intent of enhancing flight location, collision avoidance, and weather information services for these operations (Safety Recommendations A-06-21 and -22 and A-07-25 and 26).

In addition, following the 2006 midair collision involving a business jet and a transport-category airplane over Brazil that claimed 154 lives, we recommended requirements for equipment that could provide pilots with enhanced alerts regarding the status of transponder and traffic collision-avoidance capabilities (Safety Recommendations A-07-35 through -37).

We note that, in December 2009, the FAA completed the implementation of ADS-B for the Gulf of Mexico, as recommended. Accordingly, Safety Recommendation A-06-21 is classified CLOSED—ACCEPTABLE ACTION.

From J. Randolph Babbitt, Administrator: The Federal Aviation Administration (FAA) completed the implementation of the Automatic Dependent Surveillance-Broadcast (ADS-B) for the Gulf of Mexico. It was declared operational in December 2009. ADS-B coverage provided to the Gulf of Mexico includes the entire operating airspace for helicopter operations. In addition to the 21 operational ADS-B radios that provide coverage offshore in the Gulf of Mexico, the FAA also installed voice communications and weather observation systems, which provide additional services over the airspace served by the hundreds of helicopters operating in the Gulf of Mexico.

I believe the FAA has effectively addressed this safety recommendation and I consider our actions complete.

On June 15, 2006, the FAA provided a briefing for the Safety Board on the ADS-B program including the plans for this program to be installed and operational in the Gulf of Mexico before the end of FY-2010. Pending completion of the ADS-B system for the Gulf of Mexico before the end of FY-2010, Safety Recommendation A-06-21 is classified OPEN -- ACCEPTABLE RESPONSE.

Letter Mail Controlled 7/17/2006 4:17:14 PM MC# 2060341: - From Marion C. Blakey, Administrator: An extensive briefing on the ADS-B program was provided to the Board Members and staff by the FAA program manager on June 15,2006, which included a discussion of the progress of the program for the Gulf of Mexico. A copy of the presentation materials for that briefing is enclosed. I will keep the Board informed on the progress of this program for the Gulf of Mexico.