The North Atlantic (NAT) airspace is a capacity bottleneck and traffic is still increasing. New technologies and procedures such as Performance Based Communication and Surveillance (PBCS) are implemented in order to reduce the minimum lateral and longitudinal separation, hence increasing capacity in the NAT airspace.

Operators may benefit from increased route options and optimum flight level allocation in the NAT Region based on FOCA approval and the application of relevant PBCS requirements. The airspace usage optimisation of the NAT Region is based on additional tracks that are spaced by one-half degree of latitude within the core tracks of the NAT OTS from Flight Level FL 350 to FL 390.
Notice
From 29 March 2018, flights will be required to indicate compliance with the Performance based Communication and Surveillance (PBCS) specifications in order to qualify and benefit from reduced lateral and/or longitudinal separation minima.
Operators that would like to benefit from increased route options and optimum flight level allocation in the NAT Region from 29 March 2018 are required to obtain FOCA approval. In order to grant the approval process to be accomplished before 29 March 2018, the operator shall submit form 44.20 and all relevant documents, at latest by 31 December 2017.
Guidance Material and Forms
FOCA has created Guidance Material/Information (GM/INFO) «Performance Based Communication and Surveillance in the ICAO North Atlantic Region», where the criteria for PBCS and the requirements for operators are stipulated.
FOCA GM/INFO - Performance Based Communication and Surveillance in the ICAO North Atlantic Region (PDF, 413 kB, 06.10.2017)Keywords: PBCS, NAT HLA, RCP 240, RSP 180, PBN, ADS-C, ADS-B
Background Information
2015
- SLOP (Strategic Lateral Offset Procedures) : mandatory to fly 0, 1 or 2 nm right of track
- RLatSM (Reduced Lateral Separation Minima) : spacing on the NAT Tracks reduced to 'Half Track' (30 nm) for 3 core tracks
2016
- NAT HLA (North Atlantic High Level Airspace) : the airspace formerly known as MNPS changed to NAT HLA. This includes Bodo Oceanic
- RNP (Required Navigation Performance) : aircraft must be RNP4 or RNP10
- Confirmation of assigned route : 'confirm assigned route' will be sent when entering NAT airspace with datalink
2017
- TCAS (Traffic Alert and Collision Avoidance System) : TCAS 7.1 is required throughout the entire NAT region
- Contingency Procedure : a new turnback procedure is introduced
- Datalink Mandate (DLM) Exemptions : Tango routes, airspace north of 80N and New York OCA
- Gross NAV Error : Defined as greater than 10 nm (before 25 nm)
- Cruising Level : ICAO standard cruising level no longer needed to be filed
2017
- 07 December - Phase 2B : DLM airspace FL 350 to FL 390 (inclusive) throughout the ICAO NAT region (up to then only NAT OTS)
2018
- 29 March - PBCS : Introduction of performance based communication and surveillance (PBCS)
2020
- 30 January - Phase 2C : DLM airspace FL290 and above throughout the entire ICAO NAT region
Advancements in aircraft avionics and air traffic management flight data processing systems resulted in an initiative to analyse whether the lateral separation standard in the current North Atlantic High Level Airspace (NAT HLA) could be reduced from 60 nm to 25 nm thereby increasing the number of route options available and capacity at optimum flight levels. An ongoing trial implementation of 25 nm lateral separation, referred to as Reduced Lateral Separation Minimum (RLatSM), has established tracks that are spaced by one-half degree of latitude with the inclusion of an extra track between the core tracks of the NAT Organised Track System (OTS) from FL 350 to FL 390 inclusive. Phase 2 will extend the trial to the whole of the NAT OTS and is planned to commence by the end of 07 December 2017.
A similar trial has been ongoing in the Shanwick Oceanic Control Area (OCA) to reduce longitudinal separation between aircraft following the same track to 5 minutes. This initiative is referred to as Reduced Longitudinal Separation Minimum (RLongSM). These trials will be terminated on 29 March 2018. However, the application of both reduced lateral and longitudinal separation will still be possible after this date with the introduction of Performance Based Communication and Surveillance (PBCS). This AIC sets out the criteria for PBCS and the requirements for operators to continue using airspace where PBCS separations (i.e. reduced separations) are being applied.
Further Information
Last modification 15.02.2022