EMAS: Engineered Material Arresting System
EMAS: Engineered Material Arresting System
EMAS: Engineered Material Arresting System
EMAS: Engineered Material Arresting System
EMAS: Engineered Material Arresting System
Sometime it may happen that aircraft overrun the end of runway which results in devastating results. The phenomena “overrun” in field of the aeronautics occur when the aircraft passes beyond the end of a runway during an aborted takeoff or on landing rollout. To minimize the hazard of overrun, FAA (Federal Aviation Administration) introduced the concept of RSA (Road Safety Area); beyond the end of runway, into airport design standards. For the most commercial airports of the world RSA extends for 1000 feet with 500 feet width. The extension of runway implemented in the event of aircraft overruns, undershoots and veers off the side of the runway.
The most dangerous incidents among these are overruns. There are many airports worldwide which don’t follow RSA (1000 ft. and 500 ft.) standards because the airports were already built before the introduction of RSA concept. Some airports can’t achieve this standard model due to obstacle like water bodies, highways, railroads etc. But the safety is too important. Under the circumstances where RSA cannot be implemented, the concept of EMAS is used. EMAS stands for Engineered Material Arresting System. It is an acceptable alternative to RSA which provides level of safety equivalent to full RSA.
EMAS uses material of controlled strength and density place at the end of a runway to stop or greatly slow an aircraft that overruns the runway. The best material for purpose to date is a lightweight crushable concrete. When the aircraft overruns and enters the EMAS arrestor bed, tires of aircraft sink into the lightweight concrete and aircraft is decelerated by having to roll through material. Here is the list of some major accidents reported in USA.
Incidents:
To date, there have been several incidents listed below where the EMAS technology has worked successfully to arrest aircraft that overrun the runway. All cases have resulted in minimal to do damage to the aircraft. The only known injury was an ankle injury to a passenger during egress following the arrestment:
May 1999—A Saab 340 commuter aircraft overran the runway at John F. Kennedy International Airport (JFK).
May 2003—A Cargo McDonnell Douglas (MD)-11 overran 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 (KGMU) in Greenville, South Carolina.
July 2008—An Airbus A320 overran the runway at O’Hare International Airport (ORD).
January 2010—A Bombardier CRJ-200 regional jet overran the runway at Yeager Airport (KCRW) in Charleston, West Virginia (WV).
October 2010—A G-4 Gulfstream overran the runway at Teterboro Airport (KTEB) in Teterboro, New Jersey (NJ).
November 2011—A Cessna Citation 550 overran the runway at Key West International Airport (KEYW) in Key West, Florida.
Role of pilots
Pilots needs to know what EMAS is because engaging EMAS at the end of the flight, shouldn’t be desired outcome and pilot should have knowledge of how to identify EMAS region on the airfield diagram and on airfield. Pilots should know about that EMAS may or may not stop light weight general aircraft that is not heavy enough to sink in crushable concrete.
