- You can make a crossing at FL280 or below, or FL430 or above
- You can cross via the Iceland-Greenland corridor if you have ADS-B
- You can enter NY Oceanic, the Bodo and Azores corridors, GOTA, and fly down T9/290.
Datalink is defined as CPDLC and ADS-C. If you’re missing either CPDLC or ADS-C, then you’re not datalink equipped. Since 2021, datalink is mandated (DLM) for the entire NAT region between FL290-410 [NAT Doc 007, Ch 1.8]. The only exception is flights STS/FFR, HOSP, HUM, MEDEVAC, SAR, or STATE.
Without datalink, you can only enter these areas on the North Atlantic FL290-410 [NAT Doc 007, 1.8.2]:
- Anywhere north of 80N
- New York Oceanic East
- The Iceland-Greenland Surveillance corridor (ADS-B required west of 30W)
- The Bodo corridor (ADS-B required)
- The Azores corridor (ADS-B required)
- Tango 9 and 290 (ADS-B required) (per UK AIP)
- GOTA (ASD-B not required but please do if you can, says ATC)
The only complete crossing available is therefore via the Iceland-Greenland corridor. For this, you need ADS-B west of 30W.
So, if you have ADS-B, and the remaining NAT HLA requirements, you can make a crossing at normal altitudes (eg. FL380) through this airspace.
For planning purposes, this area is bounded by the following:
Northern boundary: 65N000W – 67N010W – 69N020W – 68N030W – 67N040W – 69N050W – 69N060W – BOPUT.
Southern boundary: GUNPA (61N000W) – 61N007W – 6040N010W – RATSU (61N010W) – 61N020W – 63N030W – 6330N040W – 6330N050W – EMBOK. [NAT Doc 007, 1.8.5]
If you don’t have ADS-B, then this crossing is not available between FL290-FL410.
In this case, you should plan to cross the ocean at FL280 or below, or FL430 or above. This in turn places you outside the NAT HLA, as the HLA levels are FL285-FL420. A crossing at FL280 may mean a fuel stop, in Iceland for example (BIKF or BIRK are commonly used).
You can request a climb or descent through Datalink Mandated airspace from ATC, and this is commonly granted, but you do need HLA approval.
Santa Maria Corridor
The Santa Maria Corridor will allow you to fly out to the Azores and back, but won’t help with a full NAT crossing due to the gap between Santa Maria surveillance and the New York oceanic boundary. To use this corridor, you need a Mode S transponder with extended squitter for ADS-B. [NAT Doc 007, 1.8.5 b]
This didn’t answer your question?
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Useful links for more on this …
- NAT Timeline – new rules, year by year
- NAT Datalink – current rules
- NAT Doc 007 (ICAO)
More on the topic:
- More: 2025 North Atlantic Plotting & Planning Chart
- More: Greenland NAT Alternates – Major Changes Coming
- More: NAT Ops: Flying the Blue Spruce Routes
- More: NAT Guide 2025 – My First NAT Flight is Tomorrow
- More: NAT Circle of Entry (2025)
More reading:
- Latest: Dodging Danger: The Three Routes Through the Middle East
- Latest: US Pre-Clearance: How does it work?
- Latest: 2025 North Atlantic Plotting & Planning Chart
- Safe Airspace: Risk Database
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Why is it Fl 430, can I not cross without Datalink at Fl 420 ?
Hi James,
There is no “FL420”, as RVSM tops out at FL410. The next level above is FL430.
Cheers – Mark.
Check ICAO Doc 10037 Global Operational Data Link (GOLD) Manual. The bible for all things data link…which in fact 2 words. Lipstick.
What would be the contingency if you are CPDLC equipped and datalink fails before you coast out into Ganders airspace east bound. Would we have to stay at FL280 and request a fuel stop in Iceland or Shannon?
Hi Nick, sorry I missed your comment earlier. NAT Doc 007 basically says “talk to ATC”. In practice, you should be able to continue at normal levels, but it depends on traffic. See NAT Doc 007, 1.8.4.b.
Is the route CYYR-BGSF still available at FL290-410 if you have both NAT HLA approval and ADS-B but no datalink?
Hi Chris. Techincally yes, it’s available – if you route via GOTA (No DLM applies) and stay out of Gander OCA proper. But, you would likely be running into a lot of crossing traffic on the NAT, so the chances of actually getting above FL290 are strongly reduced. It does depend on NAT traffic on the day, and working something out with Gander in advance makes sense. I’d say overall more likely than not you’d be capped at FL290-FL330 on that route. Let me know if you find out any different?