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North Atlantic High Level Airspace (NAT HLA) airspace exists in the North Atlantic between Flight Level 285 and Flight Level 420. It includes Gander Oceanic, New York Oceanic East, Reykjavik, Santa Maria, Bodo and Shanwick Oceanic Control Areas (OCA). This airspace was formerly referred to as MNPS airspace until redesignation as NAT HLA February 2016.

Certain NAT HLA routes have unique equipment and operational approval requirements. Specified tracks in the Organized Track System (OTS) require CPDLC FANS 1/A equipment, which requires a separate FAA authorization. Other routes require HF communications equipment, single or dual Long Range Navigation Systems (LRNS).


Aircraft operating in NAT HLA airspace are required to meet specified horizontal navigation performance through the carriage and proper use of navigation equipment that meets identified standards and has been approved by the FAA. Pilots are required to follow appropriate operating procedures.

Aircraft may be flown below FL 285 or above FL 420 in NAT HLA airspace without B036 and B039 approvals, traffic and ATC permitting.



When submitting a new NAT HLA Letter of Authorization (LOA) application to the FAA, Operators are required to now also submit an RNP-4 or RNP-10 application. Operators with an existing MNPS Letter of Authorization must update their LOA before January 30, 2020.


The FAA’s LOA for NAT HLA can be issued with certain restrictions and limitations based on the aircraft performance and equipment capability. Operation can be restricted to non-HF comm routes only or to Single Long Range Navigation (SLRNS) routes.

The pilots must complete training in NAT HLA and RNP-10/RNP-4 airspace and the applicant is required to submit an aircraft equipment list that includes navigation and communications equipment installed on the aircraft.


FAA review timeframe and requested documentation for RNP-10/RNP-4 and NAT HLA applications varies widely. Applications are reviewed by the operator’s local FSDO and then uploaded to an online database for an FAA regional navigation office inspector to review. Each regional office has their own requirements for what constitutes a compliant application.

Some offices require the operator’s pilot to meet in person at the FSDO to attend a tabletop discussion covering NAT HLA operations procedures and aircraft equipment requirements. Inspectors must determine that the pilot has sufficient knowledge of international and oceanic operations procedures prior to issuing the LOAs.

Refer to the RNP-10/RNP-4 section of this manual for more detailed information on the application process.



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