Engineered materials arrestor system
An engineered materials arrestor system, engineered materials arresting system (EMAS), or arrester bed is a bed of engineered materials built at the end of a runway to reduce the risk of a runway excursion. Engineered materials are defined in FAA Advisory Circular No 150/5220-22B as "high energy absorbing materials of selected strength, which will reliably and predictably crush under the weight of an aircraft". 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. The purpose of an EMAS is to stop an aircraft overrun with no human injury and minimal aircraft damage. The aircraft is slowed by the loss of energy required to crush the EMAS material. An EMAS is similar in concept to the runaway truck ramp made of gravel or sand. It is intended to stop an aircraft that has overshot a runway when there is an insufficient free space for a standard runway safety area (RSA). Multiple patents have been issued on the construction and design on the materials and process.
FAA Advisory Circular 150/5220-22B explains that an EMAS may not be effective for incidents involving aircraft of less than 25,000 pounds weight. It also clarifies that an EMAS is not the same as a stopway, which is defined in FAA Advisory Circular 150/5300-13A, Section 312.
As of May 2017, the International Civil Aviation Organization (ICAO) has been working on developing a harmonized regulation regarding arresting systems.
Research projects completed in Europe have looked into the cost-effectiveness of EMAS. Although arrestor beds have initially been installed at airports where the runway safety areas are below standards, their ability to stop aircraft with minimal or no damage to the air frame and its occupants has proven to bring results far beyond the cost of installations. 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 over $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.
United States installations
The FAA's design criteria for new airports designate Runway Safety Areas (RSA), to increase the margin of safety if an overrun occurs, and to provide additional access room for response vehicles. A United States federal law required that the length of RSA in airports was to be 1,000 feet (300 m) by the end of 2015, in a response to a runway overrun into a highway at Teterboro Airport in New Jersey. At airports built before these standards were put into effect, the FAA has funded the installation of EMAS at the ends of the main runways. The minimum recommended overall length of an EMAS installation is 600 feet (180 m), of which at least 400 feet (120 m) is to consist of the frangible material.
As of July 2014[update], 47 United States airports had been so equipped; the plan was to have 62 airports so equipped by the end of 2015. As of May 2017[update], over 100 EMAS have been installed at over 60 US airports.
As of May 2017[update], there were two recognized EMAS manufacturers worldwide that meet the FAA requirements of Advisory Circular 150-5220-22B, “Engineered Materials Arresting Systems for Aircraft Overruns.” (The FAA must review and approve each EMAS installation.)
The first, original EMAS was developed in the mid-1990s by Zodiac Arresting Systems (then known as ESCO/Engineered Arresting Systems Corp.) as part of a collaboration and technical acceptance by the FAA. EMASMAX® (fourth generation EMAS) arrestor beds are composed of blocks of lightweight, crushable cellular cement material, encased in jet blast resistant protection, designed to safely stop airplanes that overshoot runways. Zodiac’s latest, most durable EMAS is installed on over 110 airport runways at over 65 airports on three continents. Zodiac's EMAS has undergone intense testing, including several live aircraft test runs at speeds up 55 knots and is the world’s first and only EMAS that has safely stopped aircraft in real emergency overrun situations at commercial airports.
Runway Safe EMAS (second generation EMAS) is a foamed silica bed made from recycled glass and is contained within a high-strength plastic mesh system anchored to the pavement at the end of the runway. The foamed silica is poured into lanes bounded by the mesh and covered with a poured cement layer and treated with a top coat of sealant.
Runway Safe EMAS has been installed to replace older EMAS at Chicago Midway. Runway Safe has also installed an EMAS at Zurich airport 2016.
There is a third manufacturer, certified by the Chinese CAAC, with a product that is very similar to the original one of Zodiac ESCO.
On May 1, 2017, the FAA issued a summary citing twelve incidents of aircraft stopped by EMAS, involving a total of 284 passengers and crew:
- In May 1999, a Saab 340 commuter aircraft with 30 persons aboard overran the runway at JFK.
- In May 2003, a Gemini Cargo MD-11 cargo aircraft with 3 persons aboard overran the runway at JFK.
- In January 2005, a Boeing 747 cargo aircraft with 3 persons aboard overran the runway at JFK.
- In July 2006, a Mystere Falcon 900 business aircraft with 5 persons aboard overran the runway at Greenville Downtown Airport in South Carolina.
- In July 2008, an Airbus A320 commercial airliner with 145 persons aboard overran the runway at Chicago's O'Hare Airport.
- On 19 January 2010, a Bombardier CRJ-200 commercial regional airliner with 34 persons aboard overran the runway at Yeager Airport in Charleston, West Virginia after a rejected takeoff.
- On 1 October 2010, a G-4 Gulfstream business aircraft with 10 persons aboard overran the runway at Teterboro Airport in Teterboro, New Jersey.
- On 2 November 2011, a Cessna Citation II business aircraft with 5 persons aboard overran the runway at Key West International Airport in Key West, Florida.
- In October 2013, a Cessna 680 Citation business aircraft with 8 persons aboard overran the runway at Palm Beach International in West Palm Beach, Florida.
- In January 2016, a Dassault Falcon 20 aircraft with 2 persons aboard overran the runway at Chicago Executive Airport, in Chicago, IL
- In October 2016, A Boeing 737 aircraft with 37 persons aboard, including Republican Vice-Presidential Candidate Mike Pence, overran the runway at LaGuardia Airport, NY. 
- In April 2017, A Cessna 750 Citation aircraft with 2 persons aboard overran the runway at Bob Hope Airport in Burbank, CA
In addition, the following incidents have been described in other news outlets:
- After the 8 December 2005 overshoot of Southwest Airlines Flight 1248 at Midway International Airport in Chicago, Illinois, which is located in a heavily congested area, an EMAS was installed on Rwy 13C/31C.
- On 13 October 2006, New York Yankees Alex Rodriguez's private jet was brought to a halt safely by the EMAS installation at Bob Hope Airport in Burbank, California. The system was installed after the 2000 Southwest Airlines Flight 1455 runway overshoot that injured 43 passengers and the captain.
- Boburg, Shawn (17 September 2013). "Teterboro Airport gets $1M for runway project". northjersey.com. Retrieved 5 May 2014.
-  FAA Advisory Circular 150/5220-22B (PDF)
-  FAA Advisory Circular 150/5300-13A (PDF)
- Jacobs, Kenneth (1 March 2006). "Runway Safety Areas - An Airport Operator’s Perspective". Federal Aviation Administration. pp. 8, 9, 13. Archived from the original on 27 September 2012. Retrieved 20 August 2014.
- FAA AC 150-5220
- Runway Risk, Flying, September 2014 issue, p. 57
- FAA Fact Sheet – Engineered Material Arresting System (EMAS)
-  FAA Fact Sheet
- "PSA Airlines Canadair CRJ-200 N246PS operating as US Airways flight 2495 from Charleston, West Virginia (CRW) to Charlotte, North Carolina (CLT) with 30 passengers [sic] and 3 crew, overran the runway following a rejected take-off. The aircraft was stopped by the EMAS at the end of the runway, sustaining only minor damage to its landing gear doors."
- "Private jet overshoots runway at Teterboro Airport". Archived from the original on 29 March 2012. Retrieved 28 October 2016.
- "A Cessna Citation landed at Key West. The flight, which originated in Fort Lauderdale with 3 passengers and 2 crew, had a brake failure upon landing in Key West and was successfully stopped by the airport's newly installed EMAS. Only minor injuries were reported."No one is hurt after small plane crash lands at Key West Airport". NJ.com. 4 November 2011. Retrieved 24 August 2012.
- "Aviation Accident Brief ERA12IA060". NTSB.
- "EMAS Saves Falcon 20 at Chicago Executive". Aviation International News. Retrieved 2017-05-16.
- Mele, Christopher (2016-10-27). "Plane With Mike Pence Aboard Skids Off La Guardia Runway". The New York Times. ISSN 0362-4331. Retrieved 2016-10-28.
- Walker, Karen (2016-10-27). "LaGuardia runway EMAS saves US VP candidate aircraft". Air Transport World. Retrieved 2016-10-29.
- Hradecky, Simon. "Accident: Eastern Air Lines B737 at New York on Oct 27th 2016, overran runway on landing long". avherald.com. Retrieved 2016-10-30.
- "KMDW Airport Diagram" (PDF). Retrieved 7 January 2008.
- Oldham, Jennifer (14 October 2006). "Yankee Player's Jet Overruns Runway in Burbank". Los Angeles Times.
The airport installed the $4-million safety system after a Southwest Airlines Boeing 737 skidded off the same runway and onto a street in 2000, injuring 43 passengers and the captain on the same runway.
- EMAS at The FAA website
- Gulfstream II stopped by EMAS at Burbank
- “Rethinking Overun Protection" - Aerosafety World, Aug. 2006 (Three EMAS Saves: 1999, 2003, 2005)
- "EMAS Saves Falcon 20 at Chicago Executive"
- Patent No. 6,726,400; Vehicle arresting bed systems
- Patent No. 5,902,068; Vehicle arresting unit fabrication methods
- Patent No. 5,885,025; Vehicle arresting bed systems
- Patent No. 5,789,681; Arresting material test apparatus and methods