North Atlantic Regional Data Link Mandate: Part 2 – NAT DLM Roadmap

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North Atlantic Regional Data Line Mandate – Part 2: NAT DLM Roadmap

This business aviation blog post continues from our article last week, entitled "North Atlantic Regional Data Link Mandate: Part 1 – Implementation."

The objective of the North Atlantic Data Link Mandate (NAT DLM) is to improve communication, surveillance, and air traffic control intervention capabilities within the North Atlantic Track (NAT) region. Operators should be familiar with implementation of phase 2 of NAT DLM as part 2A will go into effect February 5, 2015. Ensure flight plans are filed correctly, with all applicable navigation (nav) equipment categories completed.

The following is an overview of what you need to know:

1. Mandate objectives

The goal by 2018 is to have 90% of aircraft operating in NAT airspace – at Flight Level (FL) 290 and above – equipped with Future Air Navigation System (FANS 1/A) or equivalent Automatic Dependent Surveillance-Contract (ADS-C) and Controller-Pilot Data Link Communications (CPDLC) equipment. By 2020 the objective is to have 95% of aircraft transiting the NATs to be equipped as above.

2. NAT DLM implementation

Phase 2A of the NAT DLM commences February 5, 2015, and covers all NATs within the NAT Organized Track System (OTS) from FLs 350 to 390 inclusive. For more information on NAT DLM, please see our article entitled: North Atlantic Data Link Mandate – What You Need to Know. Note that this applies to all aircraft operating on or at any point along these tracks. Phase 2B goes into effect December 7, 2017, and covers operations FLs 350-390 inclusive throughout the International Civil Aviation Organization (ICAO) NAT Region. A little farther down the road, commencing January 30, 2020, new requirements will cover operations at FL 290 and above throughout the ICAO NAT Region. When all these changes have been implemented, the term "Minimum Navigation Performance Specification" will no longer be used. In its place will be the term "Performance-Based Navigation Environment," in line with ICAO 2012 long-term goals.

3. ATS surveillance airspace

This is airspace where surveillance is provided by radar and/or automatic dependent surveillance –broadcast (ADS-B) coverage. Within the boundaries of Air Traffic Service (ATS) surveillance airspace, you may operate without CPDLC so long as the aircraft is suitably equipped (transponder/ADS-B Extended Squitter transmitter) and the entirety of the flight planned route is within ATS surveillance coverage. Eventually you’ll require ADS-B to travel through ATS surveillance airspace, but it’s unknown at this time when ADS-B mandates will be implemented.

4. Boundaries of ATS surveillance airspace

Northern boundary: 64N000W–68N010W–69N020W–68N030W–67N040W–69N050W–70N060W– ADSAM.

Southern boundary: RATSU (61N000W) –61N020W– 63N030W– 62N040W – 61N050W-SAVRY.

5. Additional information

Additional information and ICAO documentation outlining guidelines for these changes can be found in information published by the FAA. You may also review the FAA notice issued in December 2014.


Over the long term, NAT DLM mandates, along with other future changes such as ADS-B requirements in the ATS surveillance airspace, will be positive for GA operators. Collision risks will be reduced to enable NAT Target Level of Safety to be met. One immediate benefit, even for operators not CPDLC-equipped, is that these changes will eliminate a large volume of North Atlantic communication over VHF radio.


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