Aircraft Arresting Systems

AIM ¶ 2-3-14 — Aircraft Arresting Systems

AIM 2-3-14 explains aircraft arresting gear and EMAS: runway cable markings, yellow chevrons, and how these systems affect pilots. Study guide for checkrides.

In Plain English

AIM 2-3-14 describes two types of aircraft arresting systems you may encounter, especially at joint civil/military airports.

Emergency Arresting Gear is designed to rapidly stop military aircraft. It typically consists of:

Pendant cables supported above the runway by rubber "donuts"
Most installations are in the overrun areas, but some cables cross the operational runway near the ends

When a cable crosses the runway, it must be identified by 10-foot diameter solid circles painted in identification yellow, spaced 30 feet on center perpendicular to the centerline across the full runway width. Importantly, normal aircraft operations on the runway are not restricted by the presence of arresting gear.

Engineered Materials Arresting Systems (EMAS) are a different concept. EMAS is built from high energy-absorbing material located in the safety area beyond the runway end and is marked with yellow chevrons. The material is designed to crush under the weight of commercial aircraft, decelerating them through the landing gear during an overrun. EMAS does not affect normal takeoff or landing operations, but it can be as close as 35 feet beyond the runway end. Pilots and ground vehicles should never taxi or drive across EMAS or past the runway end where EMAS exists — doing so will damage the system and potentially the aircraft.

AIM Source Text

FAA AIM ¶ 2-3-14

2-3-14. 2-3-14. Aircraft Arresting Systems Certain airports are equipped with a means of rapidly stopping military aircraft on a runway. This equipment, normally referred to as EMERGENCY ARRESTING GEAR, generally consists of pendant cables supported over the runway surface by rubber “donuts.” Although most devices are located in the overrun areas, a few of these arresting systems have cables stretched over the operational areas near the ends of a runway. Arresting cables which cross over a runway require special markings on the runway to identify the cable location. These markings consist of 10 feet diameter solid circles painted “identification yellow,” 30 feet on center, perpendicular to the runway centerline across the entire runway width. Additional details are contained in AC 150/5220-9, Aircraft Arresting Systems for Joint Civil/Military Airports. NOTE- Aircraft operations on the runway are not restricted by the installation of aircraft arresting devices. Engineered Materials Arresting Systems (EMAS) . EMAS, which is constructed of high energy-absorbing materials of selected strength, is located in the safety area beyond the end of the runway. EMAS will be marked with yellow chevrons. EMAS is designed to crush under the weight of commercial aircraft and will exert deceleration forces on the landing gear. These systems do not affect the normal landing and takeoff of airplanes. More information concerning EMAS is in AC 150/5220-22, Engineered Materials Arresting Systems (EMAS) for Aircraft Overruns. NOTE- EMAS may be located as close as 35 feet beyond the end of the runway. Aircraft and ground vehicles should never taxi or drive across the EMAS or beyond the end of the runway if EMAS is present. FIG 2-3-42 Engineered Materials Arresting System (EMAS)

Oral Exam Questions a DPE Might Ask

Q1What runway markings indicate an aircraft arresting cable crosses the runway?

Per AIM 2-3-14, an arresting cable crossing the runway is marked with 10-foot diameter solid circles painted 'identification yellow,' spaced 30 feet on center, perpendicular to the runway centerline across the entire runway width.

Q2What is EMAS, where is it located, and how is it marked?

Per AIM 2-3-14, EMAS (Engineered Materials Arresting System) is constructed of high energy-absorbing material located in the safety area beyond the end of the runway — possibly as close as 35 feet from the runway end. It is marked with yellow chevrons and is designed to crush under the weight of an aircraft to decelerate it through the landing gear.

Q3Do aircraft arresting systems restrict normal runway operations, and what should pilots avoid?

Per AIM 2-3-14, normal aircraft operations on the runway are not restricted by the installation of arresting devices. However, aircraft and ground vehicles should never taxi or drive across EMAS or beyond the runway end when EMAS is present, since the material is designed to crush under aircraft weight.

Related Paragraphs in AIM Chapter 2

¶ 2-3-1

Airport Markings and Signs

¶ 2-3-10

Airport Direction Signs

Runway Distance Remaining Signs

¶ 2-3-15