Engineered materials arrestor system

While the current technology involves lightweight, crushable concrete blocks, any material that has been approved to meet the FAA Advisory Circular can be used for an EMAS.

FAA Advisory Circular 150/5220-22B explains that an EMAS may not be effective for incidents involving aircraft of less than 11,000 kilograms (25,000 lb) weight.

[3] Pilots are advised, if they know the airplane is going to overrun onto an EMAS installation, to maintain directional control of the aircraft and roll straight into it.

The latest report, "Estimated Cost-Benefit Analysis of Runway Severity Reduction Based on Actual Arrestments", shows how the money saved through the first 11 arrestments has reached a calculated total of 1.9 billion USD, thus saving more than $1 B over the estimated cost of development (R&D, all installations worldwide, maintenance and repairs reaching a total of USD 600 million).

The study suggests that mitigating the consequences of runway excursions worldwide may turn out to be much more cost-effective than the current focus on reducing the already very low probability of occurrence.

[1] At airports built before these standards were put into effect, the FAA has funded the installation of EMAS at the ends of main runways.

[11] In November 2024 Wellington International Airport (NZWN / WLG) in New Zealand also announced that part of a NZ$500m programme of infrastructure works will include the installation of an EMAS system and thus provide a small increase in the operational length of the runway.

The EMAS installation occurred as part of a wider airfield improvement programme that took place in 2019 that included the resurfacing of the runways.

The fourth generation EMAS arrestor beds are composed of blocks of lightweight, crushable cellular concrete material, encased in jet blast resistant protection, designed to safely stop airplanes that overshoot runways.