A publication of the National Air Traffic Controllers Association
Issue link: http://natca.uberflip.com/i/977826
A fl ight test was conducted Feb. 27 to examine the effect of ADS - B Duplicate I CAO Address on ERAM and STARS. Engineering assumptions have always been that when this condition occurs with two aircraft within 6nm, the SBS network would either drop the tra cks, swap the tracks or other. The initial results of the flight test show the even ts are much more conservative. Test aircraft as far apart as 50nm were still dropped from the network and p resented as radar only target s. The SBS Article 114 work group has concluded that Duplicate ICAO Address alerts are not worthwhile for controllers, and an effort is underway to remove them from all ATC a utomation systems. They will still be available for Flight Standards compliance mo nitoring efforts. NATCA SBS continues to work with the Agency toward a more proactive approach to ADS - B avionics issues that result in position error. Though these are infrequent occurrences, the Agency's ability to respond has been hampered by a lack of resources, bureaucracy, and legal constraints. These issues occur when standards for installation or configuration within aircraft or ground systems are not met. ADS - B is a cooperative surveillance source relying on position accuracy determined onboard the aircraft. Multiple ATSAP reports have been file d on the known issues to date. Controllers and facilities are encouraged to report any identified events through ATSAP and any other mechanism. In order to reduce the number of safety compromising events in the NAS an effective, efficient response mechanism is needed. The Agency has deployed additional mitigations including enhanced validation (EV) and a No Services Aircraft List (NSAL). The NSAL (aka "blacklist") is effective in dealing with chronic non - c ompliant aircraft, but it lacks t he ability to respond quickly. As such it will likely always be needed as a backstop to compliance or enforcement issues. An issue identified and reported immediately takes a minimum of one day to place the aircraft on the NSAL. Enhanced validation (EV) shows the most promise operationally as it is a real - time res ponse to invalid ADS - B targets. The latest update to EV already deployed within 15nm around a Terminal Rad ar has shown positive results. Additional EV techniques are being analyzed, including expanding the range beyond 15nm and further increasing the responsiveness. SBS Engineering is working diligently with Harris to incorporate these changes with add itional EV parameters in 2018. With 2020 approaching, rapidly, these changes are needed sooner than later to limit the sporadic effects of non - compliant avionics. SBS Article 114 work group discussions resulted in all B787 aircraf t being placed on the NSAL. These aircraft have a latent avionics issue that causes fals e position information to b e displayed to the controller. This has alarmed several facilities and caused both SCT and NCT to demote ADS - B in their sort cell priorities. Boeing released a Service Bu lletin to address the problem. United, American and many o thers have confirmed completing the Service Bulletin allowing the m to be removed from the NSAL. Other B787 aircraft are slowly being pulled off of the NSAL as verification of the Service Bulletin is received by Flight Standards. Advanced IM AIRS Working G roup to meet 1st week of May. Growing concerns surrounding American's equipage timeline not aligning with program timeline.