ATSAP Success Story: L.A. Center and RNP Capabilities
Thursday, November 01, 2012

Los Angeles Center (ZLA) Controllers noticed a problem the very first day they began using a new performance-based navigation procedure. Fortunately, an ATSAP report helped quickly resolve the issue.

There was no issue with the RNAV standard arrival procedure itself. It worked fine.

However, because the procedure utilized RNAV STAR, aircraft are required to have arrival RNP values of 1.0 or greater. To fly the STAR, a pilot must include the aircraft’s capabilities in the flight plan.

Most airlines file that information in the correct format, and the User Request Evaluation Tool (URET) can process it and list the STAR in blue as the preferential procedure. One airline, however, was not filing correctly.

That meant controllers had to click and drag information several times to make sure URET would process the airline’s aircraft for the preferential STAR — a time consuming task.

If controllers or airlines manually enter the information, or enter it incorrectly, the automation system at Southern California TRACON would process the flight plan on another routing, even though the flight had been cleared verbally for the preferential STAR.

That could lead to confusion between controllers and pilots, and potentially result in a safety incident. What’s more, the time controllers spend clicking and dragging is time they aren’t spending scanning their scopes for potential conflicts. And if the issue persisted as more RNAV procedures were introduced, controllers handling heavy traffic elsewhere in Los Angeles Center’s airspace simply wouldn’t have time to update the aircraft’s RNAV qualifiers.

Steve Fragas, a front line manager, brought the issue to the Airspace and Procedures office at ZLA. They then contacted the airline’ flight operations who said they’d look into the issue, but nothing changed. Therefore, Fragas filed an ATSAP report.

“It was something that needed to be done to help the controllers do their job,” he said. “I felt the ATSAP report would raise the flag and bring attention to the issue. And it did, very quickly.”

The ATSAP report raised awareness of the issue within the ATO. Mike Blake, NATCA’s ATSAP Representative on the Safety Committee and the Union’s co-lead on the Confidential Information Sharing Program, emailed the airline’s head of safety. She then sent the message to the airline’s flight ops, and within three weeks the airline had fixed the problem.

The airline also alerted other airlines operating in the region to the issue and the steps they’d taken — including pilot and dispatcher training — to resolve it. That will help other airlines avoid a similar problem.

Now the airline’s flights enter ZLA’s airspace with their RNP capabilities properly filed in their flight plans, and controllers clear them for the preferential arrival without issue.