October 8, 2010
Contact: Marcia Alexander-Adams
The Federal Aviation Administration (FAA) requires that commercial airports, regulated under Part 139 safety rules and federally obligated, have a standard Runway Safety Area (RSA) where possible. 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. The most dangerous of these incidents are overruns, but since many airports were built before the 1,000-foot RSA length was adopted some 20 years ago, the area beyond the end of the runway is where many airports cannot achieve the full standard RSA. This is due to obstacles such as bodies of water, highways, railroads, and populated areas or severe drop-off of terrain.
The FAA has a high-priority program to enhance safety by upgrading the RSAs at commercial airports and provide federal funding to support those upgrades. However, it still may not be practical for some airports to achieve the standard RSA. The FAA, knowing that it would be difficult to achieve a standard RSA at every airport, began conducting research in the 1990s to determine how to ensure maximum safety at airports where the full RSA cannot be obtained. Working in concert with the University of Dayton, the Port Authority of New York and New Jersey, and the Engineered Arresting Systems Corporation (ESCO) of Logan Township, NJ, a new technology emerged to provide an added measure of safety. An Engineered Materials Arresting System (EMAS) uses materials of closely controlled strength and density placed at the end of a runway to stop or greatly slow an aircraft that overruns the runway. The best material found to date is a lightweight, crushable concrete. When an aircraft rolls into an EMAS arrestor bed, the tires of the aircraft sink into the lightweight concrete and the aircraft is decelerated by having to roll through the material.
Benefits of the EMAS Technology
The EMAS technology provides safety benefits in cases where land is not available, where it would be very expensive for the airport sponsor to buy the land off the end of the runway, or where it is otherwise not possible to have the standard 1,000-foot overrun. A standard EMAS installation extends 600 feet from the end of the runway. An EMAS arrestor bed can still be installed to help slow or stop an aircraft that overruns the runway, even if less than 600 feet of land is available.
Current FAA Initiatives
The Office of Airports prepared an RSA improvement plan for the runways at approximately 575 commercial airports in 2005. This plan allows the agency to track the progress and to direct federal funds for making all practicable improvements, including the use of EMAS technology. Of the approximately 1,000 RSAs at these airports, an estimated 60 percent have been improved to full standards, and an estimated 79 percent have been improved to the extent practicable.
Presently, the EMAS system developed by ESCO using crushable concrete is the only system that meets the FAA standard. However, FAA has conducted research through the Airport Cooperative Research Program (ACRP) that examined a number of alternatives to the existing approved system. ACRP Report 29, Developing Improved Civil Aircraft Arresting Systems, published in January 2010, provides the industry with the most up-to-date and complete resource on potentially viable materials that can be used in future arresting systems. More information on the project, including a free copy of the report, can be found at the Transportation Research Board web site at http://www.trb.org/ACRP/.
Many of the EMAS beds installed prior to 2006 need periodic re-painting to maintain the integrity and functionality of the bed. FAA is working with ESCO to develop a retrofit of the older beds with plastic lids that are used on newer installations. The lid should eliminate the need for the periodic re-painting. The FAA’s Technical Center and ESCO continue to conduct research that will further improve EMAS.
To date, there have been seven incidents where the technology has worked successfully to arrest aircraft which overrun the runway and in several cases has prevented injury to passengers and damage to the aircraft.
- May 1999: A Saab 340 commuter aircraft overran the runway at JFK
- May 2003: A Gemini Cargo MD-11overran the runway at JFK
- January 2005: A Boeing 747 overran the runway at JFK
- July 2006: A Mystere Falcon 900 overran the runway at Greenville Downtown Airport in South Carolina
- July 2008: An Airbus A320 overran the runway at ORD
- January 2010: A Bombardier CRJ-200 regional jet overran the runway at Yeager Airport in Charleston, WVA
- October 2010: A G-4 Gulfstream overran the runway at TeterboroAirportinTeterboro, NJ.
Currently, EMAS is installed at 51 runway ends at 35 airports in the United States, with plans to install 8 EMAS systems at five additionalU.S.airports.
|Airport||Location||# of Systems||Installation Dates|
|JFK International||Jamaica, NY||2||1996(1999)/2007|
|Minneapolis St. Paul||Minneapolis, MN||1||1999(2008)|
|Little Rock||Little Rock, AR||2||2000/2003|
|Rochester International||Rochester, NY||1||2001|
|Baton Rouge Metropolitan||Baton Rouge, LA||1||2002|
|Greater Binghamton||Binghamton, NY||2||2002|
|Greenville Downtown||Greenville, SC||1||20023**|
|Barnstable Municipal||Hyannis, MA||1||2003|
|Roanoke Regional||Roanoke, VA||1||2004|
|Fort Lauderdale International||Fort Lauderdale, FL||2||2004|
|Dutchess County||Poughkeepsie, NY||1||2004**|
|Boston Logan||Boston, MA||2||2005/2006|
|Laredo International||Laredo, TX||1||2006|
|San Diego International||San Diego, CA||1||2006|
|Chicago Midway||Chicago, IL||4||2006/2007|
|Merle K (Mudhole) Smith||Cordova, AK||1||2007|
|Charleston Yeager||Charleston, WV||1||2007|
|Wilkes-Barre/Scranton Intl.||Wilkes-Barre, PA||2||2008|
|San Luis Obispo||San Luis Obispo, CA||2||2008|
|Newark Liberty International||Newark, NJ||1||2008|
|Charlotte Douglas International||Charlotte, NC||1||2008|
|St. Paul Downtown||St. Paul, MN||2||2008+|
|Worcester Regional||Worcester, MA||2||2008/2009**|
|Reading, Regional||Reading, PA||1||2009**|
|Kansas City Downtown||Kansas City, MO||2||2009+/2010|
|Smith Reynolds||Winston-Salem, NC||1||2010|
|New Castle County||Wilmington, DE||1||2010|
|Key West International||Key West, FL||1||2010|
|Telluride Regional||Telluride, CO||2||2010|
( ) Bed replaced
* Widened in 2008
** General aviation airport
+ Reliever airport
Additional projects currently under contract
|Location||Number of Systems||Expected Installation Date|
|Augusta State, ME||2||2011|
|Groton-New London, CT||2||2011|