Air traffic controllers at Denver International Airport are due to get a new ground radar system that should give them better warning if a plane or truck improperly enters an active runway.
And they could get it sooner rather than later after recent incidents at DIA.
On Friday, an airport snowplow entered a runway in front of a United Airlines jet that had just landed, and on Jan. 5, a small cargo plane also entered an active runway, thinking it was a taxiway.
In the January incident, the small plane got on the runway just as a Frontier Airlines jet was landing. The Frontier plane aborted the landing and circled around to land safely.
On Friday, the United pilots used emergency techniques to stop quickly as the plow passed in front of them.
No one was injured in either incident.
The Federal Aviation Administration and National Transportation Safety Board officials continue to investigate the incidents.
Controllers in DIA’s tower use an older generation Airport Surface Detection Equipment radar known by the shorthand ASDE-3. It is designed to let tower controllers track planes and ground vehicles.
But controllers and other air traffic experts say ASDE-3 can leave “blind spots” and coverage gaps on an airfield.
At some airports around the country, the FAA has been installing an upgraded system, called ASDE-X, that is designed to eliminate blind spots.
DIA is in line to get the upgrade by March 2009, said FAA spokesman Allen Kenitzer.
It is possible that the two recent “runway incursions” at the Denver airport could speed up the installation of ASDE-X, which should give controllers at DIA much better radar coverage of the 53-square-mile airport.
Airports with ASDE-X require vehicles that operate on the airfield, such snow-removal equipment, to have transponders, Kenitzer said.
DIA’s ground vehicles do not now have the transponders, airport spokesman Steve Snyder said.
DIA officials said Tuesday the snowplow driver and an operations department employee who was in a separate vehicle nearby have been placed on administrative leave with pay pending the outcome of the investigation.
NTSB investigator Arnold Scott said the United pilots saw the snowplow drive up on an airport access road and stop at its intersection with the runway.
The pilots “came in and landed,” expecting the plow to remain short of the runway, Scott said.
“At that point, they observed the plow pull out on the runway slowly,” he said, adding that the flight crew said they then “went to significant reverse thrust and manual braking” to stop in advance of the snowplow’s path.
Staff writer Jeffrey Leib can be reached at 303-954-1645 or jleib@denverpost.com.
