Colorado & Denver News

DENVER (CBS4) ― Safety incidents on the runway at Denver International Airport have happened at least four times in the past year. Such incidents are happening across the country, and the National Transportation Safety Board is pushing for change.

There have been two dozen this year across the United States.

The NTSB says the FAA needs to address the problem and prevent near-catastrophes like the one at Denver International Airport on Feb. 2. United Flight 1193 was landing when suddenly a snowplow was spotted on the runway.

"A snowplow just taxied right out in front of us -- just came right on the runway in front of us," a pilot said in a cockpit audio recording of the incident that was obtained by CBS4 News. "We had to slam on the brakes to avoid hitting him."

How could a snowplow end up on an active runway?

"It was very perplexing and obviously very concerning to us," DIA operations manager John Kinney told CBS4. "They obviously deviated from every safety standard and safety net that we had."

DIA is one of the world's busiest and most complex airports. Approximately 4 million passengers travel through DIA each month, and keeping track of which plane goes where can be a nightmare.

On Jan. 5, during blowing snow, a Frontier flight was cleared to land on Runway 3-5 Left when a Key Lime charter plane entered onto the runway. An air traffic controller made a frantic order to the Frontier pilot, who was just 230 feet away. The two planes missed colliding by 50 feet.

"We made a wrong turn there," the charter plane's pilot said in the cockpit recording CBS4 obtained.

In July a city of Denver electrician drove his vehicle from a shed down a road at DIA, then took a wrong turn, ignoring or not seeing multiple warning markers. Then the vehicle proceeded to cross onto an active runway where a United Flight was already cleared for departure. The plane was still a safe distance away.

"The real issue here is we don't know how many runway incursions there are," aviation analyst Michael Boyd said. "They aren't fully reported."

Congress held a hearing on the threat of runway collisions on Thursday. NTSB Chairman Mark Rosenker said conditions are ripe for a runway crash.

"It is time to do something before we have to investigate an accident that is catastrophic and explain to the families that technologies are out there to begin to prevent this thing from happening," Rosenker told legislators.

To prove its point that this is now the top safety risk to the flying public, the agency released cockpit recordings and animation of near misses. The NTSB said the fact that none of those incidents resulted in a crash is simply a matter of luck.

Officials say the root of the problem is busy controllers trying to keep track of more planes than ever before.

A new radar warning system helps many airports around the country prevent runway incursions, but DIA is way down on the list to receive it -- 21st out of 35 airports. CBS4 contacted Bobby Sturgell, the head of the Federal Aviation Administration, who would only say a lot of factors are involved and they are trying to speed up the process.

Joe Ray, the head of the air traffic controllers union at DIA, said he thinks DIA "should certainly be at the top of the list."

Colorado Sen. Ken Salazar told CBS4 he is planning to write a letter to the Secretary of Transportation about the increased need for the new radar.

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