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John Lenhart (ZOA) is the Article 114 Representative for Advanced Technologies & Oceanic Procedures (ATOP).    

ATOP Program   

Background:   The ATOP system processes information consistent with system calculations or expectations (e.g. vertical movement) and provides alerts to controllers when a situation arises, or information is received that is out of conformance and/or requires attention or action.  This “control by exception” concept has enabled oceanic air traffic operations to advance to a level that would not have been possible under the previous manual system.  The ATOP system is anticipated to have the capability and maintainability to meet the future demands posed by new airborne technologies and the associated procedures.  

The ATOP system concept incorporates existing and emerging technologies into a single, integrated system.   These technologies include:   

  • Flight profile monitoring, utilizing flight data processing and surveillance data processing based on data from the following sources:  
  •  AutomaticDependent Surveillance – Broadcast (ADS-B)  
  • Primary and secondary radar  
  • Automatic Dependent Surveillance – Contract(ADS-C FANS-1/A compatible)  
  • Controller-Pilot Data Link Communications (CPDLC) position reports  
  • HighFrequency (HF) radio position reports  
  • CPDLC, (FANS-1/A compatible)  
  • Air Traffic Services (ATS) Inter-Facility Data Communications (AIDC)  
  • NAS Interfacility message set  
  • ATS Facilities Notifications (AFN) (FANS-1/A compatible)  
  • Conflict detection, prediction, and alerting (radar separation and non-radar oceanic separation)  
  • Workload monitor  

The ATOP system manages long-term conflicts (up to two hours), operational requirements (e.g. coordination, workload monitoring), and aircraft requests. The ATOP program consists of an ATOP Program Manager, NATCA National Lead, NATCA Site Leads, and operational area Subject Matter Experts (SME’s) as well as Oceanic Airspace Managers from each Site.  We also have representation from AJV-I, AJT, Site Techs, ATOP Second Level Engineering, and ATOP Contract Support.    

As May comes to a close the ATOP program saw an increase in virtual meetings but productivity has taken a hit compared to working in a normal environment. The Site leads and SME’s continue to be on operational COVID schedules and continue to do what they can to attend calls and submit requested comments and inputs.   

New York Center (ZNY) and Anchorage Center (ZAN) are up and operational on ATOP T27(03) with ZOA discussing coming up in June.  When the program discussed ways to move forward in the COVID work environment we knew some things would just not be possible.  The Sites meeting the benchmark for coming up on T28 is one of these things. Coming up on a new T-build requires travel for Site support among other dynamics that are just not possible in this current environment.  The bulk of T28 brings enhancements behind the operational scene with some functionalities desired by controllers.  Not making the benchmark does not negatively impact operational safety but does have the potential to push future enhancements to dates later than proposed.   

The program had to cancel the scheduled June Tech Center meeting which is resulting in difficulties demoing T29 functionalities to include Enhanced Trial Probe and the 23 nm Lateral Oceanic standard functionality.  We are looking into ways to demo remotely with the ability to give control to remote participants.  This can allow the Site SME’s test system and operational functionality in a limited way.   

 This Month the ATOP Program has worked collaboratively with the following Programs/Projects:  

Future of the Ocean 2035 (FOTO 2035)  

For the last 8 months a team including NATCA SME’s have been working on a vision document for FOTO 2035.  The vision document was completed and released this month for FAA internal use.  The document will help steer the development the FAA’s offshore and oceanic strategy looking forward to 2035.  Next step is working on concepts of operations in attempts to make the visions a reality.   

Acceptable Level of Risk (ALR) National Lead, Paul Behan  

The ALR project went through reorganization.  The new direction is to break off into subgroups.  Transition Hazard Area (THA’s) in the Oceanic environment will include the ATOP program working closely with the ALR team to achieve solutions.   

Spaced Based ADS-B (SBA) National Lead, Dan Hamilton  

As reported in previous reviews, the SBA and ATOP programs have been working together to create oceanic operational concepts utilizing SBA technologies.  The Programs have developed a project for each of the three oceanic sites and are in discussions on moving forward with development and demos.  MITRE has been tasked to write a CONOPS for each individual Site project.  The MITRE, ATOP and SBA met with ZAN to start the initial CONOPS.  ZNY and ZOA next.   

Functional Description Narratives FDN’s  

FDN’s are created as part of the process for any ATOP enhancement, fix, or improvement.  An FDN starts with a problem statement, which is a general description of what is desired to be accomplished within the system and why.  Then the technical aspects and systematic and operational behaviors are outlined.  FDN’s are distributed to all appropriate stakeholders for review and comment.  An FDN is required for the engineers to start a technical build. Below are the current FDN’s out for review:  

57849: Space-Based ADS-B (SBA) Oceanic Surveillance and Tracking (OST)  

56179: 20NM Longitudinal Separation  

56398: Improved Monitoring Capabilities for Communication and Surveillance Network Performance  

52339: WP1 – Auto Populate Airspace Reservation with SIGMET (SWIM):  Entering SIGMETs into ATOP is currently a manual process.  SIGMET information will be available via the SWIM interface and should automatically enter the system and be displayed to the supervisor for validation and processing.  

52335: WP1 – SWIM Services, Infrastructure and SWIM Servers:  The FAA is moving from point-to-point interfaces to SWIM.   ATOP needs to be ready for the transition and receive its current information via SWIM, when that is available.  

52334: WP – Rehost Weather – Subscribe to WMSCR:   Currently ATOP receives its wind model and forecast via a dedicated interface.  The current information and potentially more will be offered on SWIM.  ATOP should be modified to take advantage of the change in interfaces and potential additional information.  

For additional information on any ATOP subject, issue or would like to receive more technical explanations, feel free to contact me at any time. Controllers at the Oceanic Sites can also reach out to the Site Leads and SME’s. Any inputs, ideas, and feedback are always welcome from the sites. Reach out to your site leads if you have enhancement or improvement ideas.    

Below is the contact information for the NATCA ATOP Cadre and Site leads:   

BUR: JT Lenhart ATOP National Lead  


ZNY: John Fox, ZNY Lead, OCA West (WATRS) SME  


         Todd Tourin, North Atlantic SME  


ZAN: Mark Crabtree, ZAN Lead, SME  


ZOA: Donald White, ZOA Lead, Pacific North SME  


         Catherine Siu, Pacific South Siu  


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