It may not look like much, but Mercer County Airport’s EMAS crushable concrete block system could save lives if a plane overshoots the runway.

In late 2011, two small planes crash landed on the runway of a Key West airport. All the passengers were fine and so was the plane.

Other planes have crashed off the end of runways at John F. Kennedy International Airport, Teterboro Airport and Burbank Airport. One of these aircraft was a huge Boeing 747. But again, everyone was fine.

These planes would have skidded off the runways if they hadn’t been safely brought to a stop by crushable concrete. This substance, placed at the end of runways, is called an Engineered Material Arresting System, or EMAS. It works by compressing under the weight of the plane, thus bringing it to a safe stop.

The EMAS system has a 100 percent success rate. Every overshooting incident has left the passengers with no major injuries and the planes with minimal to no damage.

The system is now installed in 73 airports worldwide, including Trenton-Mercer Airport.

The EMAS project was completed in September.

“The FAA has told us that when a plane overshoots the runway and it has this EMAS system that it will not only save lives, it will save the plane from running God knows where,” said freeholder Pasquale Colavita. “The management of this airport is committed to safety and is always listening to the FAA. If there’s an opportunity to upgrade we take advantage of it.”

Colavita said installing this EMAS system is the airport’s way of taking a proactive stance on safety.

Airport manager Melinda Montgomery agreed.

“It was to best meet the FAA standards,” she said. “It’s the best thing on the market.”

The system was designed by Engineered Arresting Systems Corporation, or ESCO, along with the Port Authority and the FAA back in the ’90s. They first successfully stopped a Boeing 747 jet in 1999 after it overshot the runway at JFK airport.

“Our track record is tremendous,” said Kevin Quan, director of U.S. Sales and Marketing at ESCO. “We’ve had eight aircraft go into the EMAS system with low or mininum damage and no injury to passengers.”

About eight years ago, an aircraft overshot Runway 16 at Trenton-Mercer airport.

According to Montgomery, both occupants of the aircraft were without injury, but there was significant damage to the aircraft.

The new EMAS system would prevent such things from happening in the future.

“[Airports] have requirements for over-run areas, ‘Runway Safety Areas’, to mitigate risk,” Quan said. “At most commercial airports the RSA is 500 feet wide and extends 1,000 feet beyond each end of the runway. The FAA has this requirement in the event that an aircraft overruns, undershoots or veers off the side of the runway.”

But airports are not always able to have this extra space. Some airports are decades old and have since had towns built up around them. The EMAS system is great for airports in cramped areas, like at Trenton-Mercer airport, or for ones that are near water.

“For years they’ve been telling us that we need to meet the runway requirements, meaning that we need to have X number of feet beyond the runway as a safety area,” said Aaron Watson, director of Mercer County Department of Transportation and Infrastructure. “We don’t have that here, we’re restricted by roadway. In recent years they came up with the EMAS system so you don’t need that extended runway to have a safety area. You can have this crushable concrete and if there’s an overrun it’s safe.”

A grant from the FAA paid for 97.5 percent of the project, with the remaining money coming from the county. The project cost about $13 million and took about 90 days to install on runways 16 and 34.

“The residents should feel safe flying,” Quan said.