The number of incidents involving aircraft flying too close to each other within the National Airspace System (NAS) doubled to 4,394 in 2012, according to an air traffic safety report issued by FAA on Thursday.
FAA attributes the spike to increased reporting of the incidents, rather than an increase in the incidents themselves. The agency employed a new system that automatically records every occasion when two airplanes violate the agency's flight separation rules. In the past, FAA had relied upon controllers and pilots reporting these incidents themselves.
Although the number of incidents doubled, FAA's Air Traffic Organization (ATO) reports that out of the 133 million takeoffs and landings handled by controllers each year, more than 99 percent of them occur "completely according to procedure."
"We've gone from counting errors to identifying and mitigating safety risk," said J. David Grizzle, chief operating officer of ATO in a statement accompanying the new report. "Because of this, we're looking at the system from many angles, and identifying potential issues that might have otherwise gone undetected."
FAA requires a distance of 3.5 miles or 1,000 vertical feet of separation between any two aircraft near airports.
According to the report, there were also 18 incidents where aircraft on airport runways nearly collided with each other, although none of these occurrences resulted in a collision.
"Maintaining the safety of the world’s largest, most efficient national airspace requires constant vigilance and focus. It is a critical task that NATCA’s members take seriously and work to achieve every single day," the National Air Traffic Controllers Association (NATCA) said in a statement on Thursday.
According to the report, FAA will focus on several safety hazards that it identified from analyzing the flight separation violations and other airspace safety violation incidents, ranging from miscommunications between controllers and pilots on altitude assignments to how controllers guide aircraft into final approaches at airports.
Related: Air Traffic Management News