DENVER -- A report requested and obtained by 7NEWS shows there is an increase in dangerous close calls taking place over Colorado and eight surrounding states.

The FAA report showed that 13 times this year planes have broken a well-established safety barrier.

The number of "operational errors" this year now equals the total seen last year at the Denver Air Route Traffic Control Center. The center helps guide airlines through the airspace over Colorado and surrounding states, including Kansas.

The errors have the Air Traffic Controller's Union concerned.

"They are very serious and we don't take them lightly," said Lyle Burrington, local union president.

According to FAA protocol, planes cannot come within 5 nautical miles of one another horizontally nor 1,000 feet vertically. An operational error occurs when two planes break that barrier by half a nautical mile or 100 feet. At that point, depending on the speed, the planes could collide within seconds.

Burrington said the errors boil down to an experience issue with air traffic controllers.

"Right now we have 16-year-olds teaching 15-year-olds how to drive," he said. "We have very junior people giving on the job training to very inexperienced people."

Staffing records obtained by 7NEWS show since 2003 there has been a steady decline of certified air traffic controllers working the skies over Colorado. Six years ago, there were 313 certified controllers working at the local control center in Longmont. This year, that number has fallen to just 244, with 102 "developmental" or new controllers now on staff.

Aviation expert Michael Boyd is very critical of the FAA.

"Instead of them building the system they need and hiring the people and training them, the FAA has been reducing the system in an effort of covering up their incompetence," Boyd said.

An example of the reduction could be seen on July 9. At the peak hour of 9 a.m., there were 140 airplanes in the air headed for Denver. Only 64 of those airlines were allowed to land during that hour. The rest either had to circle the airport and hold or land elsewhere to refuel then takeoff for Denver.

Boyd said the airlines are incurring major costs with the delays when it comes to fuel and said that bill will be passed along to passengers eventually.

The union, in the meantime, is adamant that the growing inexperience problem of air traffic controllers needs to be addressed.

"These are valid concerns that need to addressed," Burrington said. "We are the watchdog for the flying public."

On a daily basis, Denver International Airport handles 1,700 takeoffs and landings on average.