C-17 missile countermeasures laser turret

Directional Infrared Counter Measures (DIRCM) are a class of anti-missile systems produced to protect

aircraft An aircraft is a vehicle that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines. ...

from

infrared homing Infrared homing is a passive weapon guidance system which uses the infrared (IR) light emission from a target to track and follow it seamlessly. Missiles which use infrared seeking are often referred to as "heat-seekers" since infrared is ra ...

missiles, primarily MANPADS and similar simple systems. Earlier infrared countermeasures like

flare A flare, also sometimes called a fusée, fusee, or bengala in some Latin-speaking countries, is a type of pyrotechnic that produces a bright light or intense heat without an explosion. Flares are used for distress signaling, illumination, o ...

s or hot block systems that produce random flashes of IR light are semi- or omnidirectional. This results in the missile seeker receiving relatively little IR energy due to the

inverse square law In science, an inverse-square law is any scientific law stating that a specified physical quantity is inversely proportional to the square of the distance from the source of that physical quantity. The fundamental cause for this can be understo ...

. DIRCM systems instead aim their IR output directly at the missile using some source of tracking information and a trainable emitter. This allows a relatively small device to overwhelm the missile seeker by focusing all of its output on it. Examples are produced by many aerospace companies, such as

Leonardo S.p.A. Leonardo S.p.A., formerly Leonardo-Finmeccanica and originally Finmeccanica, is an Italian multinational company specialising in aerospace, defence and security. Headquartered in Rome, Italy, the company has 180 sites worldwide. It is the eighth ...

, Elbit Systems,

Northrop Grumman Northrop Grumman Corporation is an American multinational aerospace and defense technology company. With 90,000 employees and an annual revenue in excess of $30 billion, it is one of the world's largest weapons manufacturers and military tec ...

ITT Corporation ITT Inc., formerly ITT Corporation, is an American worldwide manufacturing company based in Stamford, Connecticut. The company produces specialty components for the aerospace, transportation, energy and industrial markets. ITT's three businesse ...

, and BAE Systems. A Russian example is the 101KS-O.

Method of operation

The systems use an effective method of jamming infrared missile seekers through the sensor aperture and can be placed in either active or standby mode. In the standby mode, the aircrew must select the active mode to begin jamming

infrared Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from aroun ...

(IR) threats. The pulsing flashes of IR energy confuse the missile guidance system, preventing the tracking of the target aircraft.

Systems

AN/AAQ-24 Nemesis

The AN/AAQ-24 system, or "Netted Emulation of Multi-Element Signatures against Integrated Sensors" (NEMESIS), is a directional infrared countermeasure (DIRCM) system. It consists of a missile warning system ( AN/AAR-54), an integration unit, a processor, and laser turrets (Small Laser Transmitter Assembly, SLTA). Early versions of this system used an arc lamp to generate the jammer

signal In signal processing, a signal is a function that conveys information about a phenomenon. Any quantity that can vary over space or time can be used as a signal to share messages between observers. The '' IEEE Transactions on Signal Processing' ...

. The newer versions of this system produced by

use diode-based pump systems and are known by the name GUARDIAN. These systems are intended for potential fitting to commercial carriers pending the completion of multiple tests on the viability of such options. The AN/AAQ-24 system is installed in the Northrop Grumman Guardian system marketed for commercial aircraft. The system will be installed by 2025 on

C-17 Globemaster III The McDonnell Douglas/Boeing C-17 Globemaster III is a large military transport aircraft that was developed for the United States Air Force (USAF) from the 1980s to the early 1990s by McDonnell Douglas. The C-17 carries forward the name of tw ...

MC-130 The Lockheed MC-130 is the basic designation for a family of special mission aircraft operated by the United States Air Force Special Operations Command (AFSOC), a wing of the Air Education and Training Command, and an AFSOC-gained wing of the ...

, CV-22, and the CH-53E Super Stallion. Large Aircraft Infrared Counter-Measure system (LAIRCM) was a US Military requirement for protecting its large aircraft from infrared-guided missiles. The AN/AAQ-24 Nemesis system was produced to serve this requirement. LAIRCM-Lite is a C-17 program that uses a combination of laser jamming DIRCM and flares due to the limited availability of LAIRCM components.

101KS-O

The 101KS-O is a DIRCM system mounted on the

Sukhoi Su-57 The Sukhoi Su-57 (russian: Сухой Су-57; NATO reporting name: Felon) is a twin-engine stealth multirole fighter aircraft developed by Sukhoi. It is the product of the PAK FA (russian: ПАК ФА, russian: label=short for, Перспек ...

fighter jet. It has sensors that are placed in turrets, which are mounted on two points: the dorsal spine and the forward fuselage under the cockpit. It uses modulated laser-based countermeasures to confuse or destroy incoming missiles' tracking mechanisms. The 101KS-O is the first DIRCM that is deployed on any fighter aircraft.

References

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Global Security

External links