We’ll use this page for NAT changes, including EGGX/Shanwick, CZQX/Gander, BIRD/Iceland, ENOB/Bodo, LPPO/Santa Maria, and KZWY/New York Oceanic East.


Here are the latest important changes for the NAT. These are also published in the latest edition of NAT Doc 007, April 2019.

  • PBCS From March 29th 2019, there may be more than just three daily PBCS tracks. They will continue to be only FL350 to FL390 inclusive and only on the designated tracks during the period the tracks are in effect. There may be days where there are no PBCS tracks, 3 PBCS tracks, 5 PBCS tracks, potentially even all the tracks.
  • Contingency Procedures From March 29th 2019, new contingency and weather deviation procedures were introduced. For contingencies, you now turn at least 30 degrees and offset by 5 NM. For weather deviations, you now do your 300ft up/down offset when 5 NM away from track.
  • ASEPS That stands for ‘Advanced Surveillance Enhanced Procedural Separation’, and it’s a new trial that’s being implemented on the NAT using ADS-B in the Shanwick, Gander and Santa Maria FIRs. Compliant aircraft will see a reduction in longitudinal separation to as close as 14 NM. This is not restricted to particular tracks or altitudes, just between properly equipped aircraft – you’ll need RVSM/HLA approval, ADS-B, and to be fully PBCS compliant (that means meeting the specifications of RNP4, RCP240 and RSP180).

And there will be more! Keep an eye on this page, we’ll keep it updated.

The NAT used to be simple. Fill your flask, fire up the HF, align the INS and away you went.

Now, it’s a little more complicated. Basic Instruments are not enough. Use this quick and dirty guide from OPSGROUP to figure out where you are welcome on the NAT, depending on what equipment and training you have. Valid May 20, 2019.

Free for OpsGroup, or you can purchase a copy here.


  • PBCS From March 29th 2018, PBCS is a requirement for the daily mandated PBCS NAT Tracks (right now, that the 3 core tracks each day) between FL350-390.  PBCS for the NAT means having both RCP240 (4 minute comms loop) and RSP180 (3 minute position reporting). If you’re missing approval for either, then you can fly anywhere other than along the core NAT tracks FL350-390. Read more about PBCS in our article, and check out the NAT Circle of Change for an easier graphical representation.
  • RLAT  From January 4th 2018, Shanwick and Gander increase the number of RLAT tracks – most tracks between FL350-390 will now be RLAT – 25nm separation between them.


  • SLOP – Offsetting is now mandatory. Choose 0, 1, or 2nm right of track. We think 1 or 2 is best. Consider the recent A380 story.
  • TCAS 7.1: From January 1st, 2017, TCAS 7.1 is required throughout the entire NAT region.
  • Cruising Level: Effective 2017, you no longer need to file an ICAO standard cruising level in NAT airspace.
  • Gross Nav Error: This is now defined as greater than 10nm. Everywhere else in the world, it’s 25nm.
  • Datalink Mandate Exemptions: Since Dec 2017, datalink now required throughout the NAT Region from FL350-390. Exempt areas: Tango Routes, airspace north of 80N, Surveillance airspace, Blue Spruce routes, and New York OCA.


  • Confirm Assigned Route Introduced August 2016, you will see this message when you enter NAT airspace with datalink, and you should reply with the planned route in NAT airspace. Designed to catch errors.
  • NAT HLA The airspace formerly known as MNPS. Changed February 2016. NAT HLA = NAT High Level Airspace. Now includes Bodo Oceanic, and aircraft must be RNP 4 or RNP10. Previous MNPS approvals good through 2020.


  • RLAT Started December 2015, spacing on the NAT Tracks reduced to “Half Track” (30nm) for 3 core tracks. RLAT=Reduced Lateral Separation Minima. Next phase of this (ie. all NAT Tracks 350-390) was introduced in Dec 2017.
  • SLOP Offsetting right of track by 1nm or 2nm became Mandatory.

May 20, 2019: FSB updated the full NAT Crossing Guide “My first North Atlantic Flight is tomorrow“.

– What’s different about the NAT, changes from 2015-2019, NAT Quick Map
– Routine Flight Example
– Non Routine-Flights: No RVSM, No RNP4, No HF, 1 LRNS, No HLA, No ETOPS, No TCAS, No Datalink – what you can do and where you can go
Take a look.

Declan Selleck

Declan Selleck

Declan is a Flight Service Specialist with Flight Service Bureau.


  • […] For the latest changes and updates on the North Atlantic, including our most recent Guides and Charts, use our NAT reference page at flightservicebureau.org/NAT. […]

  • […] For the latest changes and updates on the North Atlantic, including our most recent Guides and Charts, use our NAT reference page at flightservicebureau.org/NAT. […]

  • […] For the latest changes and updates on the North Atlantic, including our most recent Guides and Charts, use our NAT reference page at flightservicebureau.org/NAT. […]

  • David Mumford says:

    I read the contingency turn-back procedure as follows:
    FIRST turn at least 45 degrees, THEN maintain 10/15nm offset track (depending on whether you can/cannot maintain your assigned flight level), THEN climb or descend to get out of the way of the rest of the NAT traffic (above FL410 or below FL280), THEN maintain a flight level which differs from those normally used (by 1000ft if above FL410, or by 500ft if below FL410)… and then finally once all that’s done you can initiate your turn-back.

  • Steve Thorpe says:

    It is also contained in the NAT OPS Bulletin 2015_003 Revision 4, effective 25 JAN 2017. Section 5.8.

  • Greg L says:

    I have a question related to what Dave H brought up. I found the same section (13.3.5) that FSB included in their reply to Dave H. I understand that it is relevant to RLatSM because it recommends an offset of only 15nm, but it is not specific to a turn-back as it specifies “…while subsequently maintaining a same direction 15 NM offset track…”. So if I am reading it correctly, it is suggesting that you continue in the same direction, but offset 15nm, and then descend/climb as appropriate before making any turn across the OTS or making a turn-back. Am I understanding this correctly?

  • Norm G says:

    Do you have a link to the V.2017? All I can find is V.2016-1. Thanks!

  • FSB says:

    Hi David, yep, the source is the new NAT Doc 007 –

    Page 17: “Modifications to the Contingency Procedures, to take account of possible turn-backs when operating in RLatSM airspace, are included in Chapter 13.”

    13.3.5 Before commencing any diversion across the flow of adjacent traffic or before initiating any turn-back (180°), aircraft should, while subsequently maintaining a same direction 15 NM offset track , expedite climb above or descent below the vast majority of NAT traffic (i.e. to a level above FL410 or below FL280), and then maintain a flight level which differs from those normally used: by 1000 ft if above FL410, or by 500 ft if below FL410. However, if the pilot is unable or unwilling to carry out a major climb or descent, then any diversion or turn-back manoeuvre should be carried out at a level 500 ft different from those in use within the NAT HLA, until a new ATC clearance is obtained.

  • David H says:

    I cannot find a source reference for the “Contingency Procedure: Published January 2017, a new turn-back (180) procedure is introduced – turn back to parallel previous track by 15nm.” Are you able to provide a link? Thx

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