"They took a guess," an air traffic controller who was in the Denver International Airport tower at the time said. "They were wrong."
At least 30 airplanes - with hundreds of passengers - in one of the nation's busiest air spaces were put "in a very dangerous situation," the controller reported later.
Controllers at airports across Colorado reported similar safety concerns on average three times a month last year.
The number of safety concerns reported by air traffic controllers in Colorado soared in 2010, an analysis of NASA records shows. In addition, the number of near mid-air collisions reported by pilots in Colorado skies during the past decade may be as much as three times higher than the Federal Aviation Administration publicly reports.
The concerns come to light as a wave of controller retirements is set to peak next year, hitting Colorado particularly hard.
The analysis and this article were prepared by the staff at I-News, a nonprofit journalism collaborative based in Denver. This article contains additional insight and information from 9NEWS aviation analyst Greg Feith, a former lead investigator for the NTSB.
Experts say the skies are safe. But they predict a shakeout as a wave of veteran controllers, pilots and mechanics reach retirement next year.
Mike Naiman is one of the Colorado controllers set to retire next year. Naiman says officials in both Congress and the FAA need to pay special attention to the coming wave of retirements - a warning he says veteran controllers have been sounding for years.
"We kept telling them: You're going to see a lot of people go," Naiman said.
I-News analyzed 10 years' worth of air safety reports and found that Colorado's air traffic controllers reported 32 serious safety concerns last year, ranging from confusion during severe weather to too many trainees in control facilities. There were more reports of serious events and hazards last year than the previous five years combined.
Opinions differ on why the number of reports increased.
FAA officials downplayed the surge. Some controllers said it may reflect a new reporting system launched last year. The Air Traffic Safety Action Program feeds into NASA's Aviation Safety Reporting System and allows controllers to report problems or errors without punishment. The FAA never learns their names and can't investigate.
"While the [NASA] data can be useful, it has some inherent limitations," Ian Gregor, communications manager for FAA's Western Pacific Region, said in a written statement to I-News. "The reports represent a subjective opinion or perception about an event and do not always include complete information."
"The reports that are being filed today may not be as egregious as they were years ago," Feith said.
Also, the anonymous reporting system is susceptible to abuse by disgruntled controllers and people filing reports to cover for mistakes, Feith said.
The Government Accountability Office (GAO) - the investigative arm of Congress - faulted the FAA in a report last May for failing to use the NASA data to spot national safety trends.
The GAO called NASA's system and a related system maintained by the airlines, some of which feeds into NASA's system, "The best source of information for hidden risk in the system."
The FAA also has come under criticism for its response to the retirement surge.
Congressional committees and government investigators have warned for eight years that the FAA was too slow to train a new generation of controllers, as those hired after the 1981 controllers strike reach retirement.
The agency has hired a lot of trainees in a relatively short period of time, James Simmons, a professor in the Aviation Department at Metro State College of Denver who oversees the school's air traffic controller training program, said.
"Logic would tell us that some are inexperienced and are making mistakes in some form," said Simmons, who said he has no first-hand knowledge of any problems at Colorado traffic control facilities.
The federal warnings have pointed out that the retirement situation was especially serious in Colorado.
Feith says on-the-job training of new controllers breeds distraction, which can be dangerous during critical situation.
"It's so dynamic, so complex that you really need to have people who have a high level of experience to mitigate or eliminate the potential for accidents or incidents," Feith said.
Feith says a "minor league system" that allowed controllers to gain experience in simpler environments before graduating to complex environs like Denver no longer exists.
"There are a lot of folks out there who have never been in an airplane yet they're air traffic controllers," Feith said. "The problem is that if a pilot has an issue in flight and you have no real basis for aeronautical knowledge as a controller, you may not understand what he or she is doing in that airplane."
An incident in July 2010 highlights the danger of confusion and inexperience.
The unidentified Denver controller in the July report on the landing confusion in severe weather described how airplanes had to keep circling, some running low on fuel. The report does not say why the control supervisors "guessed" at safe landing routes, but the reporting controller did say:
"There are many problems with this scenario. The first problem is that it happens way too often," the report said.
His report contained a warning.
"Too often we are setting the pilots up to fail; vectoring pilots to land and fly through level 5 and 6 thunderstorms or right into microbursts," the report said.
The same month as this incident, the U.S. House Appropriations Committee directed the inspector general to audit whether the FAA has adequate controller staffing and training at its most "critical facilities." The move came after the U.S. Department of Transportation inspector general found that too many newly trained controllers were being assigned to the nation's busiest facilities.
That report is due in May of this year.
Controllers in Colorado are responsible for 285,000 square miles of airspace over nine states. That includes some of the busiest air space in the nation.
A September 2009 staffing report by the FAA showed that the number of trainees in Colorado air traffic control centers varied greatly. In Longmont, 28 percent of the controllers were trainees, about a half at the Denver TRACON facility and a sixth at DIA.
The FAA's Gregor said his agency has caught up with retirements and is methodically training replacements, having improved its training and cut the time required to become a certified controller. What used to take three to five years now takes two to three years, he said.
"We had a big surge in retirements in 2007-2008. It was a challenge and we had to really ramp up our hiring process," Gregor said. "Now, facilities are completely, fully staffed with fully certified controllers."
But as recently as last September, a U.S. Department of Transportation inspector general report found the FAA and its contractor did not have enough instructors to handle training at several facilities, including the Colorado facility that guides planes within a 50-mile radius of DIA, known as Denver TRACON.
"As a result, several high-traffic facilities - such as New York Center and Denver TRACON - experienced significant instructor staffing shortages that compromised training programs at each location," the report said.
Terry von Thaden, air-safety researcher and private consultant at the University of Illinois Urbana-Champaign, said too many trainees in a control tower can lead to problems. Experienced controllers have become virtuosos at squeezing planes into tight airspaces, she said.
"But you bring the young people in and they are expected to keep up the same tempo and they don't have the experience," von Thaden said. "They have many more operational errors."
In addition, one controller can not effectively oversee two or more trainees while guiding airplanes.
"He can't see all the ins and outs of the subtle mistakes they are making," she said.
Von Thaden said despite the surge in reports and close calls, she believes the system works overall.
"Is it basically safe? Yes," she said.
Still, the reports can be troubling.
"Does stuff happen every day that you don't want to know about? Yes," she said. "The fact that it works always amazes me."
This story written by Burt Hubbard, I-News Network.
I-News is a Colorado-based in-depth news collaborative. For more information: www.iNewsNetwork.org.
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