On a cold day last January, the pilot of a DC-9 cleared to land at Cleveland-Hopkins International Airport on runway 5R noticed a commuter plane taxiing in his path.
It was just in time. The DC-9 pilot aborted his landing and maneuvered safely around the commuter plane.
That near miss, known in aviation jargon as a "runway incursion," was caused by simple pilot confusion. The commuter plane's crew missed a turn and strayed onto the wrong runway.
Such mishaps are rare; accidents that result from them are even rarer. But when runway accidents do occur, they can be among the most destructive, involving two planes carrying two sets of passengers. Aviation experts are now sounding alarms because the number of these potentially dangerous mishaps is growing, rapidly.
During the past four years, reports of runway incursions jumped more than 50 percent, according to the Federal Aviation Administration. That has triggered ire over perceived FAA foot-dragging on a problem that's been around since the late 1970s. It's also engendered frustration at the National Transportation Safety Board (NTSB), which has included runway incursions on its "most wanted" list of airport fixes since 1990.
But the problem has also prompted what one FAA official calls the "most cooperative effort I've ever seen" between the FAA, the NTSB, the airline industry, and pilots associations to deal with the problem.
"The program needs improvement. The trend is going up," says Willie Card, manager of the FAA's Runway Incursion Program. "But I think we've zeroed in on the problem, and I expect to see the numbers turn around very soon."
Causes of runway incursions are as varied as the terrain at the nation's 476 towered airports. They range from pilot inattention, to poorly marked runways, to confusing signals from air-traffic controllers, to badly designed runways - what one pilot called "malfunction junctions."
But the primary cause, according to some aviation experts, is simple congestion. With more people flying, there's a lot more ground traffic for controllers to handle.
"The more aircraft that are on the ground, the heavier the workload is in the tower," says Clint Oster, an aviation economist at Indiana University at Bloomington. "That always raises the possibility that a controller may not be able to keep such close tabs on a plane."
The FAA is focusing on what it calls "low-tech and high-tech" solutions. These involve things as simple as requiring that runways be painted regularly and as complex as multimillion-dollar ground-based radar. It's also homing in on the most significant cause of the increase in incursions: pilot error.
In 1996, there were 287 runway incursions in the US. More than half were caused by pilots failing to do things like stop short of an active runway. More than 70 percent of the pilot deviations involved general-aviation aircraft, the smaller, noncommercial planes.
That's one area the FAA is targeting its low-tech fixes. The agency is working aggressively with the Airline Owners and Pilots Association (AOPA) in Maryland to improve training of nonairline pilots.
"For most airline pilots, flying is like driving in their own neighborhoods - they routinely go to the same airports," says the AOPA's Warren Morningstar. "Contrast that with corporate and general-aviation pilots, who often fly into places they've never been."
For years, pilots had complained about bad lighting, difficult-to-understand signs, and confusing or vague markings on runways. After a runway collision in Detroit in 1991, the FAA developed its Runway Incursion Plan. It ordered airports to standardize their signs and improve lighting.
The FAA acknowledges that more can and should be done. In January, it's expected to come out with a revised incursion plan that may include recommendations for things like standardized paintings of runways and taxi routes, improved lighting, and increased radio frequencies at some of the busier airports to be sure communications are clear between controllers and pilots.
The FAA's high-tech solutions are also in the works, although they've been slower in coming. In 1976, the NTSB recommended that the FAA develop a ground-based-radar system to help air-traffic controllers handle increasing ground traffic. A year later, at Tenerife in the Canary Islands, two 747 jumbo jets collided on the runway and 583 people lost their lives. It is the worst accident in civil-aviation history.
It wasn't until 1990 that the FAA awarded a contract. The systems, known as Airport Surface Detection Equipment (ASDE-3), were to be installed at all major airports by 1995. That was delayed by several years. To date, 27 of 40 systems have been commissioned. A companion computer system to ASDE that sends out warning signals to controllers was to be operational by 1996, but it's been delayed until 2000.
"The FAA has been working on the different problems associated with ASDE for 15 years," says Aaron Gellman, director of the Transportation Center at Northwestern University. "It's not a simple problem, but it should have been achieved long ago."
At $7 million a pop, ASDE systems are too expensive for most medium-size and small airports. So the FAA is looking for a less-expensive "off the shelf" version for them.
Some aviation watchers, however, say the answer may not be more fixes but simply less air traffic on the ground.
"Some of these ultra-busy airports have reached ground saturation," says Bruce Landsberg of the Maryland-based Air Safety Foundation, a nonprofit aviation-safety organization run by the AOPA.
During the next 15 years, that problem will only get worse: Air traffic is expected to double. And unless the current trend can be reversed, the safety risks that come from such incursions could also double.
"The real challenge is that there's a tradeoff between airport safety and airport efficiency," says James Burnett, a former NTSB chairman. "There's always a constant pressure for airports not to be as safe as they could be."