NAT FAQ: No HLA approval – Where can we go?

By Mark Zee


No HLA Approval – Where can we go?
  • You can make a crossing at FL280 or below, or FL430 or above
  • You can enter the NAT region outside HLA airspace
  • You might get special ATC approval to enter, or to climb/descend through it

The North Atlantic (NAT) High Level Airpsace (HLA) is the busiest Oceanic airspace in the world. Special approval is needed to fly in it. The NAT HLA extends from FL285-FL420, and takes in 6 different Oceanic Control Areas’s (OCA’s): Reykjavik, Shanwick (excluding SOTA & BOTA), Gander, Santa Maria, Bodo, and NY Oceanic East north of 27N.

HLA approval is issued by your country of registry, or the country of your operator.

Without NAT HLA approval, you can make a crossing at these altitudes:

  • FL280 or below
  • FL430 or above – but you should be familiar with NAT HLA procedures in case of drift-down, especially if above the NAT Tracks

ATC may approve you to (briefly) enter the HLA in some cases: if you are under radar control (or other surveillance), have VHF contact, and can navigate appropriately [NAT Doc 007, 1.5.1]

You can also get ATC approval to climb/descend through HLA airspace [1.5.2].


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Mark Zee

Mark Zee

Founder of OPSGROUP, and a former airline pilot, ATCO and flight dispatcher. Based in Christchurch, New Zealand. Email me at

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