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Dan Hamilton (SFO) is the Article 114 Representative to the SBS Office.

Automatic Dependent Surveillance – Broadcast (ADS-B)

Background:  The Surveillance and Broadcast Services (SBS) program was created to manage a program that will enable the air traffic control (ATC) system to migrate from one that relies on radar technology to a system that uses precise location data from the global positioning satellite network. An enabler of this evolution is the Automatic Dependent Surveillance-Broadcast (ADS-B) technology. With this technology, both controllers and pilots will see radar-like displays of highly accurate traffic data. The system will also provide pilots access to weather services, terrain maps, and flight information services.

Surface Surveillance

Background:  ASSC is a surface surveillance system very similar to ASDE-X. The ASSC program was developed to replace the last remaining ASDE3/AMASS sites. To date, SFO; CLE; MCI; CVG; PIT; MSY and PDX have successfully deployed. ANC and ADW will be the last two sites in the waterfall. Initially, ASSC was supposed to deploy without Surface Movement Radar (SMR). After a lengthy debate between NATCA and the Agency, it was decided that ASSC would include SMR for all sites. 

We participated in numerous telcons regarding the data analysis needed for MLAT (Multilateration) divestiture on the surface. Due to the implementation of ADS-B into the NAS, and lack of available parts to sustain MLAT at ASDE-X and ASSC sites, the agency started a program aiming to remove MLAT. It has yet to be determined if its achievable due to the early infancy of the program. Much of what I have learned on Radar divestiture will be carried over to this program. As far as completing the ASSC Rollout, ADW is currently scheduled to be finished in Fiscal Year 2022. ANC IOC (Initial operating capability) will continue to be delayed until COVID-19 restrictions are lifted. ANC was scheduled to be completed in February.

ASEPS (Space Based ADS-B)

Background:  With the terrestrial ADS-B platform fully deployed, the focus has turned to areas where surveillance is more difficult to achieve. Space Based ADS-B (SBA) utilizes low orbiting satellites to track aircraft that are ADS-B 1090ES Equipped. SBA provides updates every second, much like FUSION in STARS. SBA provides all the data controllers currently see on all platforms. It is also possible to gain additional data such as selected altitude.  The team has been working with ZMA as they are the key site for operational evaluation in the Caribbean.  As work in ZMA progresses, the team is also working with the ATOP team in the development of future concepts for SBA in the oceanic environment. Future concepts include work with ZNY; ZAN and ZOA. 

We continue daily communication and weekly telecons with the ASEPS team as we analyze space based data to determine how various issues have developed. Many of the issues we see are based on aircraft with bottom mount antennas which satellites have a hard time seeing, in addition to the poor performance of aircraft avionics.  While the team is focusing on SBA efforts at ZMA, we also have continued conversations with JT Lenhart and the ATOP team about future projects at ZNY, ZOA, and ZAN. 

We have been working with the Vehicle ADS-B team (see below) as we make modifications to the AC (Advisory Circular) on vehicles. Additional units have been added expanding the options for users, in addition to changing the procedures for installation and verification. The vehicle team has also been working with the program office in an attempt to acquire funding to equip Tech Ops vehicles.

Radar Divestiture

Andrew Stachowiak is the SBS/ADS-B/Fusion SME.

Background:  Over two years ago, the NATCA SBS team started a collaboration with the agency in efforts to optimize the NAS. Due to the implementation of ADS-B, it was realized that modifying our radar infrastructure could benefit the presentations we all use daily. 

During the FUSION Rollout, it was discovered that radar overlap, and radar reflection could

cause issues such as false targets and target “stitching.” Additionally, with ADS-B becoming a

primary surveillance source, the team agreed that it was time to start optimizing our efforts.

This program has now reached a point where communication and ongoing dialogue will begin

soon with various facilities. This will be a long and completely transparent process involving data gathering, expert analysis, local facility coordination, and a safety panel for each proposed radar removal. In some situations, additional radar feeds could be added to enhance surveillance. As this program matures, activities and other information will be updated here.

Vehicle ADS-B

Background:  Vehicle ADS-B is a program that equips vehicles with transponders so they will be visible not only by air traffic but also by airport operators. Aircraft that have ADS-B IN can also see vehicles on the flight deck. This program greatly increases safety and situational awareness in the field. Although vehicle equipage is not currently mandated, it is very much encouraged. The team that handles ASDE-X and ASSC also cover this program. There are currently 1775 vehicles equipped at 26 airports. PDX, IAD, and DCA are the latest airports to equip.

We have been keeping up with Radar Divestiture Team, SME, Technical Analysis, Communications, and Leadership meetings. On most occasions, we meet through a Zoom or Go To format to virtually look at data and or presentation material that covers every facet of the workgroup. We are collectively analyzing data and sharing information. The Radar Divestiture program is working on a website that will better explain all of this material.      

Track-Based Display Mode (TBDM)

Background:  TBDM provides controllers using ERAM with smoothed track positions rather than last-reported or extrapolated target positions.  Smoothed track positions are displayed in sync with the preferred radar sweep (4.6 or 12 secs); the use of the smoothed track position maximizes display accuracy. Reports from 0 to 8 radars along with ADS-B can be fused to form a single aircraft track. TBDM provides no changes to target/track symbology and the display update rate remains the same. TBDM enables the use of ADS-B as the preferred surveillance source to support 3NM Separation no longer limited to 3NM separation based on distance from a radar sensor. ADS-B will backfill Radar Cones of Silence and airspace beyond the distance and site limitations of existing SRRs and LRRs. New SBS Validation capabilities support significant future expansion of 3NM validation and separation anywhere in Enroute Airspace at or below FL230.  

Interval Management 

Tom Zarick is the NATCA Article 114 Center Interval Management Representative

Interval Management / ADS-B In

Background:  Interval Management, or IM, combines ground-based and flight-deck systems to provide precise inter-aircraft spacing between aircraft, providing air traffic with another tool to manage traffic flows.  The objective of the IM application is to achieve and/or maintain an assigned spacing goal (ASG) between the IM aircraft and the ATC-designated aircraft by having the pilot follow speed commands generated by the flight deck avionics.  The ASG is provided by the controller and may be given in time or distance.  

AIRS (ADSB-In Retrofit Solution) is an application within the Interval Management domain that the FAA and American Airlines are engaged in an effort to promote the benefits and viability of ADSB-In. The deployment strategy for IM will consist of three phases.  The first phase or Phase A, (similar to the AIRS concept) will consist of a subset of the IM functionality which will be limited to the same runway operations.  Phase B will introduce more complex IM operations utilizing more of the flight deck avionics that adds functionality for Dependent Staggered Approaches (DSA) and Dependent Converging and Crossing Runways (DCCR).  Phase C will introduce advanced IM capabilities that will be deployed to only a handful of facilities due to its limited benefits. 

The ERAM IM Task Team is close to completing the Interval Management Use Case document.  Unless any concerns are raised by next week, the team plans to present the document to the National User Team (NUT) on April 29th.  A lot of discussion took place this week surrounding the development of the IM status indicator.  The timeline for development appears to be moving to the left so it can support the AIRS project.  With AIRS only supporting a subset of the IM capabilities, it’s still unclear how the indicator will be defined.

Terminal Interval Management

Chris Aymond is the NATCA Article 114 Terminal Interval Management Representative

Terminal IM focuses on advanced IM applications that utilize ADS-B IN.  I am working together closely with Tom Zarick to ensure cohesion between the Enroute and Terminal environments.

IM Software Engineering meetings were held as Raytheon continues to develop the CHI for ADSB-In applications on STARS. This occurs in cooperation with SBS and the terminal CHI team. A CAS (Cockpit Display of Traffic InformationAssisted Separation) SRM Panel preparation meeting was held to begin planning for an SRM Panel for CAS. It was acknowledged that a workaround was needed to inform controllers which aircraft are CAS capable on STARS until controllers have the proper CHI. Options for this workaround are being discussed as well. The SBS office is also working with AJT to select a site for a CAS trial. Options being considered for a CAS trial are CLT, DFW, LAX, ORD, and PHL.

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