U.S. Department 

of Transportation 

Federal Aviation 

Administration 

Advisory 

Circular

Subject: Engineered Materials Arresting Systems 

(EMAS) for Aircraft Overruns 

Date: 9/30/2005

Initiated by: AAS-100 

AC No: 150/5220-22A

Change: 

1. PURPOSE. This advisory circular (AC) contains 

standards for the planning, design, installation, and 

maintenance of Engineered Materials Arresting 

Systems (EMAS) in runway safety areas (RSA). 

Engineered Materials means high energy absorbing 

materials of selected strength, which will reliably and

predictably crush under the weight of an aircraft.

2. CANCELLATION. This AC cancels AC 

150/5220-22, Engineered Materials Arresting Systems 

(EMAS) for Aircraft Overruns, dated August 28, 1998.

3. BACKGROUND. Aircraft can and do overrun 

the ends of runways, sometimes with devastating 

results. An overrun occurs when an aircraft passes 

beyond the end of a runway during an aborted takeoff 

or while landing. Data on aircraft overruns over a 12-

year period (1975 to 1987) indicate that approximately

90% of all overruns occur at exit speeds of 70 knots or 

less (Reference 7, Appendix 4) and most come to rest

between the extended runway edges within 1000 feet of 

the runway end (Reference 6, Appendix 4). 

To minimize the hazards of overruns, the Federal 

Aviation Administration (FAA) incorporated the 

concept of a safety area beyond the runway end into

airport design standards. To meet the standards, the 

safety area must be capable, under normal (dry) 

conditions, of supporting the occasional passage of 

aircraft that overrun the runway without causing 

structural damage to the aircraft or injury to its 

occupants. The safety area also provides greater 

accessibility for emergency equipment after an overrun 

incident. There are many runways, particularly those 

constructed prior to the adoption of the safety area 

standards, where natural obstacles, local development,

and/or environmental constraints, make the 

construction of a standard safety area impracticable. 

There have been accidents at some of these airports 

where the ability to stop an overrunning aircraft within 

the runway safety area would have prevented major 

damage to aircraft and/or injuries to passengers. 

Recognizing the difficulties associated with achieving a 

standard safety area at all airports, the FAA undertook 

research programs on the use of various materials for 

arresting systems. These research programs, as well as, 

evaluation of actual aircraft overruns into an EMAS 

have demonstrated its effectiveness in arresting aircraft 

overruns. 

4. APPLICATION. Runway safety area standards 

cannot be modified or waived. The standards remain in

effect regardless of the presence of natural or manmade objects or surface conditions that might create a 

hazard to aircraft that overrun the end of a runway. A 

continuous evaluation of all practicable alternatives for 

improving each sub-standard RSA is required. FAA 

Order 5200.8, Runway Safety Area Program, explains 

the evaluation process. 

FAA Order 5200.9, Financial Feasibility and 

Equivalency of Runway Safety Area Improvements and 

Engineered Material Arresting Systems, is used in

connection with FAA Order 5200.8 to determine the 

best practicable and financially feasible alternative for 

an RSA improvement. 

The FAA does not require an airport sponsor to reduce 

the length of a runway or declare its length to be less 

than the actual pavement length to meet runway safety

area standards if there is an operational impact to the 

airport. An example of an operational impact would be 

an airport’s inability to accommodate its current or 

planned aircraft fleet. Under these circumstances, 

installing an EMAS is another way of enhancing safety. 

A standard EMAS provides a level of safety that is

generally equivalent to a full RSA built to the 

dimensional standards in AC 150/5300-13, Airport

Design. It also provides an acceptable level of safety 

for undershoots. 
AC 150/5220-22A 9/30/2005 

The FAA recommends the guidelines and standards in

this AC for the design of EMAS. In general, this AC is 

not mandatory and does not constitute a regulation. It 

is issued for guidance purposes and to outline a method 

of compliance. However, use of these guidelines is

mandatory for an airport sponsor installing an EMAS 

funded under Federal grant assistance programs or on 

an airport certificated under Title 14 Code of Federal 

Regulations (CFR) Part 139, Certification of Airports. 

Mandatory terms such as "shall" or "must" used herein

apply only to those who seek to demonstrate 

compliance by use of the specific method described by

this AC. 

If an airport sponsor elects to follow an alternate 

method, the alternate method must have been 

determined by the FAA to be an acceptable means of 

complying with this AC, the runway safety area 

standards in AC 150/5300-13, and 14 CFR Part 139. 

5. RELATED READING MATERIAL. 

Appendix 4, Related Reading Material, contains a list

of documents with supplemental material relating to

EMAS. These documents contain information on 

materials evaluated, as well as design, construction, and 

testing procedures utilized. Testing and data generated

under these FAA studies may be used as input to an 

EMAS design without additional justification. 

6. PLANNING CHARTS. The figures included in

Appendix 2, Planning Charts, are for planning purposes 

only. They are intended as a preliminary screening tool 

and are not sufficient for final design. Final design 

must be customized for each installation. The figures 

illustrate estimated EMAS stopping distance 

capabilities for various aircraft types. The design used

in each chart is optimized specifically for the aircraft 

noted on the chart. Charts are based on standard design 

conditions, i.e. 75-foot set-back, no reverse thrust, and 

poor braking (0.25 braking friction coefficient). 

a. Example 1. Assume a runway with a DC-9 

(or similar) as the design aircraft. Figure A2-1 shows 

that an EMAS 400 feet in length (including a 75-foot

set-back) is capable of stopping a DC-9 within the 

confines of the system at runway exit speeds of up to

75 knots. 

b. Example 2. Assume the same runway, but

assume the design aircraft is a DC-10 (or similar). 

Figure A2-2 shows an EMAS of the same length, but

designed for larger aircraft, can stop the DC-10 within

the confines of the system at runway exit speeds of up 

to 62 knots. 

7. PRELIMINARY PLANNING. Follow the 

guidance in FAA Orders 5200.8 and 5200.9 to

determine practicable, financially feasible alternatives 

for RSA improvements. Additional cost and 

performance information for EMAS options to consider 

in the analysis can be obtained from the EMAS 

manufacturer. 

8. SYSTEM DESIGN REQUIREMENTS. For 

purposes of design, the EMAS can be considered fixed 

by its function and frangible since it is designed to fail

at a specified impact load. An aircraft arresting system

such as EMAS is exempt from the requirements of 14 

CFR Part 77, Objects Affecting Navigable Airspace. 

When EMAS is the selected option to upgrade a 

runway safety area, it is considered to meet the safety 

area requirements of 14 CFR Part 139. The following 

system design requirements must prevail for all EMAS 

installations: 

a. Concept. An EMAS is designed to stop an 

overrunning aircraft by exerting predictable 

deceleration forces on its landing gear as the EMAS 

material crushes. It must be designed to minimize the 

potential for structural damage to aircraft, since such 

damage could result in injuries to passengers and/or 

affect the predictability of deceleration forces. An 

EMAS should be design for a 20-year service life. 

b. Location. An EMAS is located beyond the 

end of the runway and centered on the extended 

runway centerline. It will usually begin at some

setback distance from the end of the runway to avoid 

damage due to jet blast and undershoots (Figure A1-2, 

Appendix 1). This distance will vary depending on the 

available area and the EMAS materials. Where the area 

available is longer than required for installation of a 

standard EMAS designed to stop the design aircraft at

an exit speed of 70 knots, the EMAS should be placed 

as far from the runway end as practicable. Such 

placement decreases the possibility of damage to the 

system from short overruns or undershoots and results

in a more economical system by considering the 

deceleration capabilities of the existing runway safety 

area. 

The resulting runway safety area must provide adequate

protection for aircraft that touch down prior to the 

runway threshold (undershoot). Adequate protection is

provided by either: (1) providing at least 600 feet (or 

the length of the standard runway safety area, 

whichever is less) between the runway threshold and 

the far end of the EMAS bed if the approach end of the 

runway has vertical guidance or (2) providing the full

length standard runway safety area when no vertical

guidance is provided. 

An EMAS is not intended to meet the definition of a 

stopway as provided in AC 150/5300-13. The runway

2
9/30/2005 AC 150/5220-22A 

safety area and runway object free area lengths begin at

a runway end when a stopway is not provided. When a 

stopway is provided, these lengths begin at the stopway

end (AC 150/5300-13). 

The airport sponsor, EMAS manufacturer, and the 

appropriate FAA Regional Airports Division/Airport

District Office (ADO) should consult regarding the 

EMAS location to determine the appropriate location

beyond the end of the runway for the EMAS 

installation for a specific runway. 

c. Design Method. An EMAS design must be 

supported by a validated design method that can predict

the performance of the system. The design (or critical) 

aircraft is defined as that aircraft using the associated 

runway that imposes the greatest demand upon the 

EMAS. This is usually, but not always, the 

heaviest/largest aircraft that regularly uses the runway. 

EMAS performance is dependent not only on aircraft

weight, but landing gear configuration and tire 

pressure. In general, use the maximum take-off weight

(MTOW) for the design aircraft. However, there may

be instances where less than the MTOW will require a 

longer EMAS. All configurations should be considered 

in optimizing the EMAS design. To the extent

practicable, however, the EMAS design should 

consider both the aircraft that imposes the greatest 

demand upon the EMAS and the range of aircraft

expected to operate on the runway. In some instances, 

this composite design aircraft may be preferable to

optimizing the EMAS for a single design aircraft. 

Other factors unique to a particular airport, such as 

available RSA and air cargo operations, should also be 

considered in the final design. The airport sponsor, 

EMAS manufacturer, and the appropriate FAA 

Regional Airports Division/ADO should consult

regarding the selection of the design aircraft that will 

optimize the EMAS for a specific airport. 

The design method must be derived from field or 

laboratory tests. Testing may be based either on 

passage of an actual aircraft or an equivalent single 

wheel load through a test bed. The design must

consider multiple aircraft parameters, including but not

limited to allowable aircraft gear loads, gear 

configuration, tire contact pressure, aircraft center of 

gravity, and aircraft speed. The model must calculate 

imposed aircraft gear loads, g-forces on aircraft 

occupants, deceleration rates, and stopping distances 

within the arresting system. Any rebound of the 

crushed material that may lessen its effectiveness must 

also be considered. 

d. Operation. The EMAS must be a passive 

system. 

e. Width. The minimum width of the EMAS must

be the width of the runway (plus any sloped area as 

necessary—see 8 (h) below). 

f. Base. The EMAS must be constructed on a 

paved surface capable of supporting the occasional 

passage of the critical design aircraft using the runway

and fully loaded Aircraft Rescue and Fire Fighting 

(ARFF) vehicles without deformation of the base 

surface or structural damage to the aircraft or vehicles. 

It must be designed to perform satisfactorily under all

local weather, temperature, and soil conditions. It must

provide sufficient support to facilitate removal of the 

aircraft from the EMAS. Full strength runway

pavement is not required. Pavement suitable for 

shoulders and blast pads is suitable as an EMAS base. 

AC 150/5300-13 provides recommendations on 

pavement for shoulders and blast pads. State highway

specifications may also be used. 

 g. Entrance Speed. To the maximum extent

possible, the EMAS must be designed to decelerate the 

design aircraft expected to use the runway at exit 

speeds of 70 knots (approach category C and D 

aircraft) without imposing loads that exceed the 

aircraft’s design limits, causing major structural 

damage to the aircraft or imposing excessive forces on 

its occupants. Contact the FAA’s Airport Engineering 

Division (AAS-100) at 202-267-7669 for guidance 

when other than approach category C and D aircraft is

proposed for the EMAS design. Standard design 

conditions are no reverse thrust and poor braking (0.25 

braking friction coefficient). 

Generally, when there is insufficient RSA available for 

a standard EMAS, the EMAS must be designed to

achieve the maximum deceleration of the design 

aircraft within the available runway safety area. 

However, a 40-knot minimum exit speed should be 

used for the design of a non-standard EMAS. For 

design purposes, assume the aircraft has all of its

landing gear in full contact with the runway and is

traveling within the confines of the runway and parallel 

to the runway centerline upon overrunning the runway

end. 

The airport sponsor, EMAS manufacturer, and the 

appropriate FAA Regional Airports Division/ADO 

should consult regarding the selection of the 

appropriate design entrance speed for the EMAS 

installation.

Note that current EMAS models are not as accurate for 

aircraft with a maximum take-off weight less than

25,000 pounds. 

3
AC 150/5220-22A 9/30/2005 

h. Aircraft Evacuation. The EMAS must be 

designed to enable safe ingress and egress as well as 

movement of ARFF equipment (not necessarily without

damage to the EMAS) operating during an emergency.

If the EMAS is to be built above existing grade, sloped 

areas sufficient to allow the entrance of ARFF vehicles 

from the front and sides must be provided. Provision 

for access from the back of the EMAS may be provided 

if desirable. Maximum slopes must be based on the 

EMAS material and performance characteristics of the 

airport’s ARFF equipment.

i. Maintenance Access. The EMAS must be 

capable of supporting regular pedestrian traffic for the 

purposes of maintenance of the arresting material and 

co-located navigation aids without damage to the 

surface of the EMAS bed. An EMAS is not intended to 

support vehicular traffic for maintenance purposes. 

j. Undershoots. The EMAS must not cause

control problems for aircraft undershoots which touch 

down in the EMAS bed. Fulfillment of this 

requirement may be based exclusively on flight

simulator tests. The tests will establish the minimum

material strength and density that does not cause 

aircraft control problems during an undershoot. 

Materials whose density and strength exceeds these 

minimums will be deemed acceptable. 

k. Navigation Aids. The EMAS must be 

constructed to accommodate approach lighting 

structures and other approved facilities within its 

boundaries. It must not cause visual or electronic 

interference with any air navigation aids. All

navigation aids within the EMAS must be frangible as 

required by 14 CFR Part 139. To meet the intent of this

regulation, approach light standards must be designed 

to fail at two points. The first point of frangibility must 

be three inches or less above the top of the EMAS bed. 

The second point of frangibility must be three inches or 

less above the expected residual depth of the EMAS 

bed after passage of the design aircraft. As a part of the 

EMAS design, the EMAS manufacturer must provide 

the expected residual depth to allow the determination

of this second frangibility point. 

l. Drainage. The EMAS must be designed to

prevent water from accumulating on the surface of the 

EMAS bed, the runway or the runway safety area. The 

removal and disposal of water, which may hinder any

activity necessary for the safe and efficient operation of 

the airport, must be in accordance with AC 150/5320-5, 

Airport Drainage. 

The EMAS design must consider ice accumulation 

and/or snow removal limitations/requirements dictated 

by the project locale. Requirements/limitations must be

addressed in the approved inspection and maintenance 

program discussed in paragraph 14 and Appendix 3. 

m. Jet Blast. The EMAS must be designed and 

constructed so that it will not be damaged by expected

jet blast. 

n. Repair. The EMAS must be designed for 

repair to a usable condition within 45 days of an 

overrun by the design aircraft at the design entrance 

speed. Note that this is a design requirement only.

An EMAS bed damaged due to an incident

(overrun/undershoot, etc.) must be repaired in a timely

manner. The undamaged areas of the EMAS bed must

be protected from further damage until the bed is 

repaired. 

9. MATERIAL QUALIFICATION. The material 

comprising the EMAS must have the following 

requirements and characteristics: 

a. Material Strength and Deformation 

Requirements. Materials must meet a force vs. 

deformation profile within limits having been shown to

assure uniform crushing characteristics, and therefore, 

predictable response to an aircraft entering the arresting 

system. 

b. Material Characteristics. The materials 

comprising the EMAS must: 

(1) Be water-resistant to the extent that the 

presence of water does not affect system performance. 

(2) Not attract vermin, birds, wildlife or other 

creatures. 

(3) Be non-sparking. 

(4) Be non-flammable. 

(5) Not promote combustion. 

(6) Not emit toxic or malodorous fumes in a 

fire environment after installation.

(7) Not support unintended plant growth with

proper application of herbicides. 

(8) Exhibit constant strength and density

characteristics during all climatic conditions within a 

temperature range appropriate for the locale. 

(9) Be resistant to deterioration due to: 

(a) Salt. 

4
9/30/2005 AC 150/5220-22A 

(b) Approved aircraft and runway

deicing fluids. 

(c) Aircraft fuels, hydraulic fluids, and 

lubricating oils. 

(d) UV resistant. 

(e) Water.

(f) Freeze/thaw. 

(g) Blowing sand and snow. 

(h) Paint. 

10. Material Conformance Requirements. An 

EMAS manufacturer must establish a material sampling 

and testing program to verify that all materials are in

conformance with the initial approved material force 

versus deformation profile established under paragraph 

9.a. Materials failing to meet these requirements 

must not be used. 

The initial sampling and testing program must be

submitted to and approved by the FAA, Office of

Airport Safety and Standards for each design method 

found by the FAA to be an acceptable means of 

complying with this AC. Once approved, the program

may be used for subsequent projects. 

11. DESIGN PROPOSAL SUBMITTAL. The

EMAS design must be prepared by the design engineer 

and the EMAS manufacturer for the airport sponsor. 

The airport sponsor must submit the EMAS design 

through the responsible FAA Airports Region/District

Office, to the FAA, Office of Airport Safety and 

Standards, for review and approval. The EMAS design 

must be certified as meeting all the requirements of this 

AC and the submittal must include all design

assumptions and data utilized in its development as 

well as proposed construction procedures and 

techniques. The EMAS design must be submitted at 

least 45 days prior to the bid opening date for the 

project. 

12. QUALITY ASSURANCE (QA) PROGRAM. A 

construction quality assurance program must be

implemented to ensure that installation/construction is 

in accordance with the approved EMAS design. The 

construction contractor and EMAS manufacturer 

prepare the construction QA program for the airport

sponsor. The airport sponsor must submit the 

construction QA program to the responsible FAA 

Airports Region/District Office for approval 14 days

prior to the project notice to proceed. 

13. MARKING. An EMAS must be marked with

yellow chevrons as an area unusable for landing, 

takeoff, and taxiing in accordance with AC 150/5340-1, 

Standards for Airport Markings. Paint application

should be in accordance with the EMAS 

manufacturers’ recommendations for the EMAS 

system.

14. INSPECTION AND MAINTENANCE. The

EMAS manufacturer must prepare an inspection and 

maintenance program for the airport sponsor for each 

EMAS installation. The airport sponsor must submit

the program to the responsible FAA Airports

Region/District Office for approval prior to final

project acceptance. The airport sponsor must 

implement the approved inspection and maintenance 

program. The program must include any necessary

procedures for inspection, preventive maintenance and 

unscheduled repairs, particularly to weatherproofing 

layers. Procedures must be sufficiently detailed to

allow maintenance/repair of the EMAS bed with the 

airport sponsor’s staff. The program must include 

appropriate records to verify that all required 

inspections and maintenance have been performed by

the airport sponsor and/or EMAS manufacturer. These 

records must be made available to the FAA upon 

request. Appendix 3, Inspection and Maintenance 

Program, outlines the basic requirements of an EMAS 

inspection and maintenance program. 

Airport personnel must be notified that the EMAS is

designed to fail under load and that precautions should 

be taken when activities require personnel to be on, or 

vehicles and personnel to be near, the EMAS. 

15. AIRCRAFT RESCUE AND FIRE FIGHTING 

(ARFF).

a. Access. As required by paragraph 8 (h), an 

EMAS is designed to allow movement of typical ARFF 

equipment operating during an emergency. However, 

as the sides of the system are typically steeply sloped, 

and the system will be severely rutted after an aircraft 

arrestment, ARFF vehicles so equipped should be 

shifted into all-wheel-drive prior to entering and

maneuvering upon an EMAS. 

b. Tactics. Any fire present after the arrestment 

of an aircraft will be three-dimensional due to the 

rutting and breakup of the EMAS material. A dualagent attack and/or other tactics appropriate to this type

of fire should be employed. 

16. NOTIFICATION. Upon installation of an 

EMAS, its length, width, and location must be included 

as a remark in the Airport/Facility Directory (AFD). 

To assure timely publication, the airport sponsor must

5
AC 150/5220-22A 9/30/2005 

forward the required information to the FAA 

Aeronautical Information Services (AIS) as soon as 

possible, but not later than the “cut-off” dates listed in

the AFD, for publication on the desired effective date. 

(The AIS address and cut-off dates are listed on the 

inside front cover of the AFD.) The airport sponsor 

must also notify the appropriate FAA Regional Airports

Division/ADO. 

The following is an example of a typical entry: 

• “Engineered Materials Arresting System, 

400’L x 150’W, located at departure end of 

runway 16.” 

When an EMAS is damaged due to an overrun or 

determined to be less than fully serviceable, a Notice to 

Airmen (NOTAM) must be issued to alert airport 

users of the reduced performance of the EMAS. 

DAVID L. BENNETT 

Director of Airport Safety and Standards 

6
 FIGURE A1-1. STANDARD EMAS INSTALLATION PROVIDES A LEVEL OF SAFETY THAT IS GENERALLY 

EQUIVALENT TO A STANDARD RUNWAY SAFETY AREA (RSA).

A1-1
A1-2 

FIGURE A1-2. EMAS TYPICAL SECTION. 
9/30/2005 AC 150/5220-22A 

Appendix 2 

APPENDIX 2. PLANNING CHARTS. 

FIGURE A2-1.

 A2-1 
AC 150/5220-22A 9/30/2005 

Appendix 2 

FIGURE A2-2.

A2-2 
9/30/2005 AC 150/5220-22A 

Appendix 2 

 A2-3 FIGURE A2-3.
AC 150/5220-22A 9/30/2005 

Appendix 2 

A2-4 

FIGURE A2-4.
9/30/2005 AC 150/5220-22A 

Appendix 2 

 A2-5 FIGURE A2-5.
AC 150/5220-22A 9/30/2005 

Appendix 2 

FIGURE A2-6.

A2-6 
9/30/2005 AC 150/5220-22A 

Appendix 2 FIGURE A2-7.

 A2-7 
AC 150/5220-22A 9/30/2005 

Appendix 2 

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A2-8 
9/30/2005 AC 150/5220-22A 

Appendix 3 

APPENDIX 3. INSPECTION AND MAINTENACE PROGRAM. 

An inspection and maintenance program, prepared by the EMAS manufacturer, will be submitted to and approved by the 

FAA Regional/Airports District Office. The Airport sponsor must implement the approved inspection and maintenance 

program. As a minimum, a basic EMAS inspection and maintenance program must address the following areas:

1. General information on the EMAS bed including 

• A description of the EMAS bed 

• Material description 

• Contact information for the EMAS manufacturer 

2. Inspection requirements including:

• Type and frequency of required inspections 

• Training of personnel

• Instructions on how to conduct each inspection 

• List of typical problems and possible solutions 

• Required documentation for inspections 

• Inspection forms 

3. Maintenance and repair procedures including:

• List of approved materials and tools 

• Description of repair procedures for typical damage to an EMAS bed such as repairing depressions/holes, 

abrasion damage, replacing a damaged block, repairing coatings, caulking/joint repair, etc. 

4. Any unique requirements due to location such as snow removal requirements and methods. Identify compatible

deicing agents. Specify snow removal equipment that is compatible with the EMAS bed and recommended clearing 

procedures and/or limitations. 

5. Warranty information 

 A3-1 
AC 150/5220-22A 9/30/2005 

Appendix 3 

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A3-2 
9/30/2005 AC 150/5220-22A 

Appendix 4 

APPENDIX 4. RELATED READING MATERIAL. 

This appendix contains a listing of documents with supplemental material relating to the subject of EMAS. These 

documents contain certain information on materials evaluated as well as design, construction, and testing procedures 

utilized to date. These publications may be obtained from the National Technical Information Service (NTIS), 

Springfield, VA 22151. 

1. DOT/FAA/PM-87/27, Soft Ground Arresting Systems, Final Report, Sept. 1986–Aug. 1987, published Aug. 1987 

by R.F. Cook, Universal Energy Systems, Inc., Dayton, OH. 

2. 2. DOT/FAA/CT-93/4, Soft Ground Arresting Systems for Commercial Aircraft, Interim Report, Feb. 1993 by

Robert Cook. 

3. DOT/FAA/CT-93/80, Soft Ground Arresting Systems for Airports, Final Report, Dec. 1993 by Jim White, Satish K. 

Agrawal, and Robert Cook. 

4. DOT/FAA/AOV 90-1, Location of Commercial Aircraft Accidents/Incidents Relative to Runways, July 1990. 

5. UDR-TR-88-07, Evaluation of a Foam Arrestor Bed for Aircraft Safety Overrun Areas, 1988 by Cook, R.F., 

University of Dayton Research Institute, Dayton, OH.

 A4-1 
AC 150/5220-22A 9/30/2005 

Appendix 4 

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A4-2