Nearly 300 U.S. commercial airports, including Chicago's Midway, lack the 1,000-foot margin at the end of the runway that the federal government considers adequate for safety.
Many are older airports squeezed next to dense city neighborhoods, bodies of water or steep drop-offs that don't have the available space.
Runway overruns can be extremely dangerous. In June 1999, an American Airlines jetliner slid past the end of the runway in Little Rock, Ark., killing 11 passengers and injuring 86. And it was only the remarkable speed of the passengers' evacuation - less than two minutes - that prevented serious injury or death when an Air France Airbus skidded off the runway in Toronto and burst into flames in August.
The Federal Aviation Administration in the 1990s began researching solutions to the runway barrier space problem and found that a certain light, crushable concrete will cause an airplane to decelerate quickly. The soft concrete bed, called EMAS for Engineered Material Arresting Systems, extends about 600 feet from the runway's end.
Planes that overrun a runway sink into the concrete, like a bit truck sinks into gravel on a runaway truck ramp on highways.
EMAS systems are in place at the end of 18 runways at 14 airports. Little Rock installed two after the 199 crash. In New York, the beds have stopped three dangerous overruns three times since May 1999 at John F. Kennedy International Airport, including a Boeing 747 in January, according to the FAA.
A bill recently passed federal law seeks to encourage more airports to build EMAS systems or extend their runway barriers by requiring them to do one or the other by 2015. There are 284 such airports, according to the FAA.
Sen. Frank Lautenberg, D-N.J., sponsored the measure after several runway overruns at his home state's Teterboro Airport, near New York. Last February, a corporate plane carrying 11 people ran off the end of the Teterboro runway during an aborted takeoff, sped across a busy road and hit a warehouse. Twenty people were injured.
"My bill, which was signed into law last week by the president, will finally force these airports and the FAA to make these runways safer," he said Friday.
Jim Hall was chairman of the National Transportation Safety Board in March 2000 when a Southwest Airlines 737 overran a runway at Burbank airport in Los Angeles, stopping within feet of a gas station.
After investigating the incident, the NTSB recommended that the FAA require big airports to upgrade runways that didn't meet safety standards.
"It's really just an accident waiting to happen," Hall said.
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