Operators accustomed to flying in the high-level North Atlantic Tracks (NAT HLA) will soon face additional compliance requirements with the March 29 implementation of performance-based communication and surveillance (PBCS) standards between FL350 and FL390 inclusive.

PBCS will replace two existing trial programs: reduced lateral separation minimum (RLatSM) and reduced longitudinal separation minimum (RLongSM). RLatSM reduces lateral separation to 25 nm, while RLongSM compresses longitudinal separation in the Shanwick Oceanic Control Area (OCA) to five minutes between aircraft in trail along the same track.

Those standards will remain under the new system, but operators wishing to fly in the affected tracks must hold a revised datalink authorization from the FAA, included in an LOA or OpSpec A056, demonstrating compliance with required communication performance 240 and required surveillance performance 180 specifications. This requires aircraft to be equipped with FANS-1/A, controller-pilot datalink communications and ADS-C.

ICAO had planned for PBCS implementation along the NAT, but a late-November pronouncement by the UK Civil Aviation Authority (CAA) drove the March deadline. “That time frame caught everyone a bit by surprise, and we're all now scrambling to get up to speed,” Mitch Launius, founder of international procedures training provider 30WestIP, told AIN.

The CAA guidance also carries a hint of what's to come. “For the time being, business aircraft that don't meet the PBCS equipage standard will be able to fly above or outside the affected tracks,” Launius explained. “However, the announcement includes the statement that the new standards ‘will be extended to the whole of the NAT HLA in due course,' and that could be quite soon.”

While the move toward tighter separation across the NAT was originally driven by the need to accommodate the high volume of commercial airline traffic across the North Atlantic, Launius noted the situation has since evolved.

"Traffic levels are constrained by the number of runways across Europe," he said. "Now, these efforts are focused on reducing fuel costs and lessening the environmental impact from those aircraft. Imagine a school of fish travelling in tight formation."

30WestIP has a free online webinar that addresses the upcoming changes, and Launius also encourages operators to review the FAA's Data Link Communications Compliance Guide to determine equipment and authorization needs.