The persistent occurrence of near-accidents on airport runways in recent years suggests “a high risk of a catastrophic runway collision occurring in the United States,” a new report to Congress warns.
Denver Internation Airport was the only U.S. airport with two incursions in the FAA’s most serious category, where “participants take extreme action to narrowly avoid a collision.”
The Government Accountability Office report, issued today, said the Federal Aviation Administration needs better coordination and leadership of its runway-safety program.
Improved technology to warn of looming runway incursions and a plan to address air-traffic controller fatigue, which some experts say contributes to the collision danger, also are needed, the report says.
The GAO found that at least 20 percent of controllers at 25 air-traffic control facilities, including some of the busiest airport towers, “were regularly working six-day weeks.”
For the fiscal year that ended Sept. 30, there were 24 serious runway incursions at U.S. airports, including the two at DIA.
One of DIA’s serious incursions occurred Jan. 5, when a small cargo plane missed a planned turn onto a taxiway and instead entered a runway as a Frontier Airline jet was about to land. The Frontier pilots saw the small aircraft on the runway and aborted the landing, seconds before DIA air-traffic controllers got warnings of the impending collision.
The second happened about a month later, when a DIA snowplow crossed a runway in front of a United Airlines jet that had just landed. The United pilots used emergency braking to stop short of the crossing plow.
This week, the National Transportation Safety Board ruled the cause of January’s near-collision was the “inadvertent entry onto the active runway” by the small plane’s pilot.
A contributing factor to the incident, the NTSB said, was the failure of controllers to detect the cargo plane’s location on the tower’s collision-warning radar displays and to issue a timely alert to the Frontier pilots.
DIA’s tower uses an older-generation surface-detection technology, and the GAO report cited an internal FAA audit from earlier this year that found the technology “was not providing consistent information to controllers.”
In the NTSB’s report on the January incident, one controller told the safety agency that there are cases where radar targets drop from tower-display screens or extra targets appear and “we’ll see things that are not there.”
The FAA audit found the “alerting process was ineffective because the delay was too long before pilots would receive the alert relayed by controllers,” GAO said.
Even an upgraded collision-avoidance technology, called Airport Surface Detection Equipment-Model X, has had reliability problems, the GAO report said. DIA is not scheduled to have a working ASDE-X system in place until November 2009, it added.
Jeffrey Leib: 303-954-1645 or jleib@denverpost.com



