Shake it off your tail! The sky is a hostile environment for military aircraft, especially with threats from fighters and ground defences to be reckoned with. In the past few years these threats have extended from the traditional combat aircraft to support aircraft and now to civilian airliners, driving a universal requirement for self-protection.The threat comes less from the weapon than the sensor, and self-protection is therefore based on thwarting the sensor. For the past 60 years the prime threat has come from radar-guided/directed weapon systems and the first line of defence has been the radar warning receiver “RWR” redirects here. For other uses, see RWR (disambiguation).
Typically fitted to military aircraft, radar warning receivers (RWR) detect the radio emissions of radar systems, whether ground-based or on-board other aircraft. (RWR RWR Radar Warning Receiver
RWR Ronald Wilson Reagan (40th President of the USA)
RWR Royal Winnipeg Rifles (Canada)
RWR Reword (proofreading) ). This provides warning of radars (on land-based or airborne weapon control sensors) or by the sensors of surface-to-air or air-to-air missiles.
A wide variety of systems are on the market, of which typical examples include the AMS AMS - Andrew Message System Sky Guardian 200, BAE Systems BAE Systems
British manufacturer of aircraft, missiles, avionics, naval vessels, and other aerospace and defense products. BAE Systems was formed (1999) from the merger of British Aerospace (BAe) with Marconi Electronic Systems. North America North America, third largest continent (1990 est. pop. 365,000,000), c.9,400,000 sq mi (24,346,000 sq km), the northern of the two continents of the Western Hemisphere. AN/ALR-56, the Elta EL/M-2160, the Elettronica ELT/156-158 and the Thales TDS TDS
total dissolved solids. family. These are all installed on a variety of platforms, often including fixed and rotary-winged, and while usually produced by one manufacturer this is not always the case. The AN/ALR-67, for example, is produced by Northrop Grumman Northrop Grumman Corporation (NYSE: NOC) is an aerospace and defense conglomerate that is the result of the 1994 purchase of Grumman by Northrop. The company is the third largest defense contractor for the U.S. (V2) and by BAE Systems/Lockheed Martin/Raytheon (V3).
All tend to be direct detection sensors using either crystal video or instantaneous frequency measurement receivers. These detectors actually provide more than mere warning, for they are digitally controlled processing systems and form the foundation of a comprehensive defensive aids suite. These systems can sort and identify all threats to the aircraft by comparing the incoming signal with an extensive threat library containing parameters of all known hostile and friendly radars. This library is usually prepared and updated by the customer.
Having identified the threat a radar warning receiver can then initiate the appropriate countermeasures where necessary, normally on a priority basis. These can be designed to shield the aircraft using electronic jammers and/or to decoy DECOY. A pond used for the breeding and maintenance of water-fowl. 11 Mod. 74, 130; S. C. 3 Salk. 9; Holt, 14 11 East, 571. threats away by the launching of chaff chaff
1. chaffed hay; called also chop.
2. the winnowings from a threshing, consisting of awns, husks, glumes and other relatively indigestible materials. or infrared expendables.
Infrared Biggest Plague, but ...
The growing electro-optical threat has also had to be addressed with ground-based weapon systems using laser targeting while the infrared seeker, which homes on the infrared signature of the aircraft's engines, has become an especially deadly threat.
Northrop Grumman has noted that only 20 percent of aircraft shot down between 1958 and 1992 fell to radar-guided threats and the remainder were lost to missiles with infrared seekers. During the first Gulf War (1990 to 1991) 75 per cent of American aircraft losses were due to the same threat that is ignored by radar warning receivers. For this reason missile warning systems integrating radar and optical seeker detectors, such as the Thales MWS-20, are frequently deployed in defensive aid suites to detect both radar and infrared guided missiles, particularly those approaching from the rear of the aircraft.
Two typical electro-optical detection systems are the Eads Missile Launch Detection System (Milds)--designated AN/AAR-60 by the United States--for rotary-wing aircraft ro·ta·ry-wing aircraft
A rotorcraft. , and the Northrop Grumman AN/AAR-54, which is compatible with high performance, fixed-wing combat aircraft and rotary-wing and support aircraft. Both use up to six sensor heads designed to detect the ultraviolet radiation of missiles, which allows the system to track them and to interface with a defensive aids suite computer to initiate the appropriate countermeasures.
To co-ordinate and integrate the operation of all aircraft protection suites a controlling system is required. Terma produces the Electronic Warfare Noun 1. electronic warfare - military action involving the use of electromagnetic energy to determine or exploit or reduce or prevent hostile use of the electromagnetic spectrum
military action, action - a military engagement; "he saw action in Korea" Management System for F-16s, although it is used in a variety of other aircraft including transports. It integrates an RWR, a jammer and a dispenser system. The system was originally designed to reduce pilot workload in the F-16.
The range of threats facing modern high-performance combat aircraft means that an increasingly sophisticated defensive aids suite is required. One example is being produced by BAE Systems Avionics BAE Systems Avionics was the avionics unit of BAE Systems until 2005, at which time it was transferred to SELEX Sensors and Airborne Systems S.p.A (initially 75% Finmeccanica and 25% BAE Systems, but since March 2007 fully owned by Finmeccanica) and was renamed , Elettronica and Indra for the Eurofighter Typhoon This article is about a fighter aircraft. For the computer game, see Eurofighter Typhoon (computer game).
“EF2000” redirects here. For the computer game, see EF2000 (computer game). as the Eurofighter Defensive Aids Sub-System (EuroDass). It consists of a defensive aids computer, an integrated radar-band electronic support and countermeasures package and a Missile Approach Warner (Maw). A Laser Warning Receiver (LWR LWR Lower
LWR Lutheran World Relief
LWR Light Water Reactor
LWR Locally Weighted Regression
LWR Laser Warning Receiver
LWR Launch When Ready
LWR Long-Wave Radiation
LWR Lakeland & Waterways Railway
LWR Long Wavelength Redundant Camera
LWR Local Wage Rate ) will be installed in British aircraft and EuroDass has a Counter-Measures Dispensing System (CMDS CMDS Christian Medical and Dental Society
CMDS Computer Misuse Detection System
CMDS Consortium for Materials Development in Space
CMDS Collection Management and Development Section (libraries)
CMDS Command Specification ) associated with, but not part of it
The defensive aids computer provides system control and allocates system resources (1) In a computer system, system resources are the components that provide its inherent capabilities and contribute to its overall performance. System memory, cache memory, hard disk space, IRQs and DMA channels are examples. , while the electronic support and countermeasures package gives the pilot immediate warning of potential threats, analyses received signals and generates information co-ordinated with aircraft sensors. The countermeasure element provides the most effective jamming techniques including the use of a towed decoy. The Maw, developed by BAE Systems and Elettronia, is an active pulse-Doppler sensor. It appears that the Typhoon typhoon: see hurricane. Batch 1 aircraft will receive a basic system with defensive aids computer and CMDS with installation of the complete system in Batch 2 aircraft.
In service on the Rafale is the Thales Spectra The Thales SPECTRA (Système de Protection et d'Évitement des Conduites de Tir du Rafale, Self-Protection Equipment Countering Threats to Rafale Aircraft) is an integrated defensive aids suite developed by Thales Group for the Dassault Rafale series of fighter aircraft. (Systeme de Protection, d'Evitement et de Contre-mesure du Rafale) integrated electronic warfare suite, which provides long-range detection, identification and accurate localisation (programming) localisation - (l10n) Adapting a product to meet the language, cultural and other requirements of a specific target market "locale".
Localisation includes the translation of the user interface, on-line help and documentation, and ensuring the images and of electromagnetic, infrared and laser threats. It consists of a phased array radar jammer, the MBDA MBDA Minority Business Development Agency (US Department of Commerce)
MBDA Michigan Broadband Development Authority
MBDA Minnesota Band Directors Association
MBDA Matra BAE Dynamics Alenia
MBDA Magnolia Ballroom Dancers' Association Samir (Systeme d'Alerte Missile Infra [Latin, Below, under, beneath, underneath.] A term employed in legal writing to indicate that the matter designated will appear beneath or in the pages following the reference.
infra prep. Rouge) and a countermeasures dispenser.
Given the greater threat from missiles with infrared seekers (some 4000 are reported to have recently vanished from a depot in Iraq), and the complexities of the subject of radar countermeasures See: electronic warfare; chaff. , this article will focus on the problems they pose to aircraft and the self-protection products required. The threat from manportable air defence systems is especially serious for, with some 500,000 delivered worldwide, they pose a threat not only to combat and support aircraft but also to civilian aircraft. In conventional combat a single soldier firing a missile worth some $ 500,000 can bring down an aircraft worth $100 million but the terrorist threat has steadily grown with some 30 aircraft brought down at the cost of some 1000 lives.
Infrared or ... Infrared?
The threat to aircraft has meant that air force transports have been routinely equipped with countermeasure systems and there are moves to extend this protection to civilian aircraft. Aircraft usually have four potential heat sources: exposed engine parts, the exhaust plume, structure warmed by aerodynamic friction and cockpit glazing, which reflects sunlight. In the two to three-[micro]m band exploited by first-generation heat seeking missiles, which remain in widespread service, hot metal is the predominant source. Energy emanating from the engines (including the exhaust plume) accounts for more than 99 per cent of the total heat signature. Skin heating becomes more important in the three to five-[micro]m band employed by more modern infrared seekers, but generally represents only about 20 per cent
The solution has been to use flares to confuse and to distract the missiles to prevent them homing in on the energy radiated by the engine, and this has led to the development of dispenser systems which ensure the flares are be dispersed at a set rate and in a sequence which would create a confusing pattern behind the aircraft. In turn the missile manufacturers developed dual-band seekers operating in the ultraviolet end of the spectrum, or the 0.2 to 0.45-[micro]m band, and in infrared, the 1.1 to 10.6-[micro]m frequency band, to distinguish between decoys and real targets and to seek the target through other sources of radiated energy. Other methods involve using processors to detect and to reject sudden rises in energy levels caused by a flare or noting and rejecting the flare to re-acquire the target.
Dual and single-band sensors continue to be available to meet differing roles. More sensitive seekers are preferred for air-to-air missiles because infrared radiation is more focused to provide an improved angle-of-arrival in most atmospheric conditions. The uncluttered background makes them easier to detect but the detectors, like the seekers, are vulnerable to atmospheric conditions and to improve sensitivity. The sensors, therefore, require cooling systems cooling systems
for housed animals include spraying of roofs with water, evaporative pads with fans, foggers and misters; for pastured animals shelter from the sun by trees or artificial shade devices and cooling ponds are used. , which effect both reliability and availability.
Ultraviolet seekers are more effective at lower and slower targets and are less vulnerable to false targets such as decoys. The sensors are smaller, lighter and require less cooling but are more vulnerable to atmospheric conditions while sensitivity and resolution are poorer.
Dispenser systems have traditionally consisted of a control unit and a programmer that controls the rate and type of cartridges expended from the dispenser. Dispensers, which use both chaff (against radar seekers) and flares, are either conformal con·for·mal
1. Mathematics Designating or specifying a mapping of a surface or region upon another surface so that all angles between intersecting curves remain unchanged.
2. or podded. The conformal systems, such as the BAE Systems AN/ALE-40 and AN/ALE-47, consist of cartridge magazines attached to the aircraft fuselage, pylons or even internally while podded systems, such as the CelsiusTech Bop and Boz family, consist of dedicated underwing units which have a larger number of dispensers and can provide longer protection.
The prime producers of chaff and flares are BAE Systems North America, Chemring, and Pyrotronics, as well as Israel Military Industries. Dedicated flare producers for aircraft include Alloy Surfaces and Kilgore Flares (part of Chemring) in the United States United States, officially United States of America, republic (2005 est. pop. 295,734,000), 3,539,227 sq mi (9,166,598 sq km), North America. The United States is the world's third largest country in population and the fourth largest country in area. as well as Britain's Wallop Defence Systems. They tend to be ejected at a speed of 25 to 45 metres/second and to burn for between two and four seconds with compositions that are designed to 'dazzle' or to confuse heat-seekers.
Flare deployment is often made on a contingency basis; an aircraft entering an area where shoulder launched missiles might be encountered will automatically begin deploying infrared munitions mu·ni·tion
War materiel, especially weapons and ammunition. Often used in the plural.
tr.v. mu·ni·tioned, mu·ni·tion·ing, mu·ni·tions
To supply with munitions. as a safeguard. The result is that aircraft appear to deploy a trail of 'comets' with bright heads and smoky trails--the problem is that this also provides a visual warning to missile operators.
If an aircraft is flying at some 4500 metres (15,000 feet) and if a shoulder-fired missile system is some eight kilometres away the operator will typically require about three seconds to identify it, two to initiate the missile, three to allow the gyros This article is about the food dish. For other uses, see Gyro.
Gyros or gyro (Greek: γύρος, "turning") (IPA: [ˈjɪːɹəʊ] to spin up and four seconds to acquire, aim and launch. With the missile likely to take between ten and twelve seconds to reach the target the total engagement sequence is about 24 seconds but this can be reduced if the target advertises its presence.
Refining the Art
Pyrotechnic manufacturers have recognised this problem and are reportedly reacting to it. The solution is to have cartridges that no longer radiate ra·di·ate
1. To spread out in all directions from a center.
2. To emit or be emitted as radiation.
ra in the visual 0.4 to 0.9-pm-band but only in the ultraviolet and infrared bands.
Alternative means of aircraft self-protection do exist, and the United States has taken the lead in the production of infrared jammers. One of the most common is the BAE Systems North America AN/ALQ-144A, which is used by some 20 customers for their helicopters. It consists of a cylindrical infrared source surrounded by a modulation screen that directs the energy at the missile.
For transport and even business jet aircraft, with customers including Air Force One, the company produces the AN/ALQ-204 Matador matador
In bullfighting, the principal performer, who works the capes and attempts to dispatch the bull with a sword thrust between the shoulder blades. Most of the techniques used by modern matadors were established in the 1910s by Juan Belmonte (b. 1894–d. : a modular system consisting of multiple transmitters and controls. Each transmitter contains a four to twelve-kW source that emits pulsed infrared radiation to combat multi-IR guided missiles. The Matador configuration is certified by the US Federal Aviation Administration Federal Aviation Administration (FAA), component of the U.S. Department of Transportation that sets standards for the air-worthiness of all civilian aircraft, inspects and licenses them, and regulates civilian and military air traffic through its air traffic control .
An alternative system developed by Northrop Grumman, BAE Systems North America and Boeing is the AN/AAQ-24 Nemesis Directional Infra-Red CounterMeasures. Now generically known as the Dircm, the Nemesis incorporates a 256 x 256 staring array A staring array, staring-plane array, focal-plane array (FPA) or focal-plane is an image sensing device consisting of an array (typically rectangular) of light-sensing pixels at the focal plane of a lens. FPAs are used most commonly for imaging purposes (e.g. fine tracking subsystem and turreted tur·ret·ed
1. Furnished with turrets or a turret.
2. Having the shape or form of a turret, as certain long-spired gastropod shells. defence system. The Nemesis detects the missile's exhaust plume using the AAR-54(V), which provides bearing data to the turret. A tracking subsystem establishes a target box in which the threat is calculated to appear and maintains turret alignment in this box for the duration of the engagement. The jamming source initially is a high-power, modulated arc lamp but this will be upgraded to a laser with demonstrations using the Fibertek Viper solid-state, diode-pumped, multiband laser source. The system is being produced for the C-130 Hercules and C-17 Globemaster III.
A European Dircm programme was announced at this year's ILA ILA
insulinlike activity exhibition in Berlin. Diehl, Eads and Thales are cooperating on electro-optical countermeasures developments to meet new threat scenarios. They have developed the Flash laser-based Dircm demonstrator, which has been trialled since last year and is intended to be part of the A400M self-protection system with later applications on other aircraft. MBDA in France is developing the Iris-400 missile warning system to complete the airlifter's self-protection system.
The demand for aircraft self-protection systems continues. In July Eads revealed it had won a contract from Denmark for 30 Milds systems, which will be installed in F-16s. Germany has also ordered the system for its helicopters; the CH-53s scheduled for Afghanistan are to be the first recipients. Thales and Eads have won a contract worth the equivalent of $ 120 million for threat warning equipment which will be installed in Eurocopter Tiger The Eurocopter Tiger is an attack helicopter manufactured by the Eurocopter Group. In Germany it is known as the Tiger; in France and Spain it is called the Tigre. It is also designated the EC 665 or PAH-2. and NH90 helicopters for European and Australian customers. The equipment consists of a Thales radar warner and an Eads laser warning receiver and will be complemented by an MBDA Saphir-M decoy system, of which more than 500 were ordered at the beginning of September in what the company claimed was largest single contract placed for such a system in Europe.
Of growing importance is the requirement to protect aircraft that would not normally be exposed to man-portable missile threats. New Delhi New Delhi (dĕl`ē), city (1991 pop. 294,149), capital of India and of Delhi state, N central India, on the right bank of the Yamuna River. , for example, has requested aircraft protection systems worth $ 40 million for three Boeing 737s used to transport government officials. The Indians want the AAQ-24, ALE-47 and the AN/ALQ-211 electronic warfare systems. The threat to government leaders and officials is credible; indeed it was the shooting down in 1994 of the Falcon 50 business jet carrying the presidents of both Burundi and Rwanda that contributed to the genocide that took place in the latter country.
Airliners in the Crosshairs
Recent incidents have shown that airliners are now becoming terrorist targets, one of the most recent being in 2002 when an Israeli aircraft leaving Mombasa in Kenya had two missiles launched against it, fortunately without success.
Since early last year the US Department of Homeland Security Noun 1. Department of Homeland Security - the federal department that administers all matters relating to homeland security
executive department - a federal department in the executive branch of the government of the United States has had a requirement for a counter-man portable missile protection system that can be installed on airliners. In August it was announced that BAE Systems Information and Electronic Warfare Systems and Northrop Grumman have each won $ 45 million 18-month Phase II system development and demonstration contracts to that end.
The BAE Systems' proposal is based on the AN/ALQ-212 advanced threat infrared countermeasures system along with the AN/AAR-57 common missile warning system, which is in production as a podded system for the US Army, the British Army and the Royal Air Force. This includes a laser jammer in a turret. The counter-man-portable missile version would be housed in a conformal pod to reduce drag.
The Northrop Grumman system, Guardian, is based on the AAQ-24 Nemesis repackaged into a conformal pod fitted onto the rear fuselage. The company will complete the design and fabrication fabrication (fab´rikā´shn),
n the construction or making of a restoration. of the prototype system for flight testing and certification in two commercial Boeing 747 and MD-11 aircraft.
When trials are completed successfully one system will be recommended for production and will undoubtedly be well placed to win orders outside the United States. Within the United States the initial application for the system is expected to be the approximately 300 wide-body airliners making up the US Civil Reserve Air Fleet A program in which the Department of Defense contracts for the services of specific aircraft, owned by a US entity or citizen, during national emergencies and defense-oriented situations when expanded civil augmentation of military airlift activity is required. , upon which the country's armed forces rely heavily for transport during times of conflict. Both companies estimate the unit cost of their system, assuming production of at least 1000, to be less than one million dollars.
The Israeli government has a similar programme and, during the 2004 Farnborough Air Show The Farnborough International Airshow is a seven-day international trade fair for the aerospace business which is held biennially in England. The airshow is organised by Farnborough International Limited, a wholly owned subsidiary of British aerospace industry's body the Society , it was revealed that Elbit's Music multi-spectral system had recently been selected to meet this requirement. The Music is essentially a Dircm-like system integrated with a missile warning suite and uses a thermal imager to acquire and to track missiles and a laser jammer supplemented by a dispenser system.
The Airliner Requirement
The requirement is to protect Boeing 737-size or larger airliners during the ten-minute periods covering take-off and landing--the envelope in which shoulder-fired missiles operate. The typical vulnerability zone around an airport is 80 kilometres long and eight kilometres wide, an area of 640 k[m.sup.2], extending up to 4500 metres. The system must have a 90 per cent probability of success against multiple missile launches or more than 80 per cent against two missiles that will hit the aircraft simultaneously. False alarms should occur no more than once every 100 takeoffs or landings, or 17 hours of operation, whichever is the lower, while the maximum specified weight is 450 kilograms. The system should raise total drag by no more than one per cent at cruise speed and altitude.