IFALPA SAFETY BULLETIN – NAT LATERAL ASEPS
On March 2019, longitudinal separation standards were reduced based on the availability of Space-Based ADS-B in the Shanwick (EGGX), Gander (CZQX), and Santa Maria (LPPO) Oceanic Control Areas in the North Atlantic (NAT), as part of the Advanced Surveillance Enhanced Procedural Separation (ASEPS) trials.

The NAT region commenced the second phase of the ASEPS trials to include reduced lateral separation starting last month, on October 2019.
The revised in-flight contingency procedure introduced on 28 March 2019 is still in effect, and with the reduced lateral separation, it is critical that the new procedures must be followed propertly in the NAT region.