Engineered Arresting Systems (Esco) has developed a third-generation coating system for its engineered materials arresting systems (EMAS) placed at the ends of runways to help prevent runway overruns of airplanes that don’t slow down in time. EMAS consists of porous concrete that absorbs energy as it buckles when an airplane rolls onto the surface.
Since 2001, EMAS areas have been painted with a jet-blast-resistant coating,
but it had to be re-applied every three years, according to Ken Thompson, Esco vice president of engineering. The new third-generation EMAS Max coating is a plastic mesh material molded into the upper surface of each EMAS block, and joints are sealed with a special tape. The new coating, which has color embedded in it, doesn’t need to be renewed every three years.
One problem with EMAS areas is that they can be hard to see, especially at night, and twice pilots at Teterboro Airport in New Jersey have taxied onto and damaged the EMAS bed. Since then, Teterboro has marked the EMAS area with reflectors mounted on frangible plastic poles. “The key is you want to delineate that area to people on the ground so they won’t damage it,” Thompson said.
Although the FAA doesn’t offer specific advice about marking EMAS areas to make them more visible, the agency is developing some guidelines, according to Thompson. The reflectors are the most common visibility marking, he added, “and where they have done that, they haven’t had any problems.” Esco currently has 25 EMASes installed at 18 airports, and 15 more are on the way. The minimum space to install an EMAS is about 200 feet, Thompson said, and the minimum FAA-required stopping capability is an airplane entering the EMAS at 40 knots and stopping by the end of the bed. Large commercial airplanes might need a bed capable of 70-knot stopping capability, which would use 300 to 400 feet at the end of the runway.