Missile approach warning system

Last updated
The cylindrical pod pointing backwards, just above the engines, is the missile approach warning receiver (part of Praetorian DASS) A Typhoon F2 fighter ignites its afterburners whilst taking off from RAF Coningsby MOD 45147957.jpg
The cylindrical pod pointing backwards, just above the engines, is the missile approach warning receiver (part of Praetorian DASS)

A missile approach warningsystem (MAW) is part of the avionics package on some military aircraft. A sensor detects attacking missiles. Its automatic warning cues the pilot to make a defensive maneuver and deploy the available countermeasures to disrupt missile tracking.

Contents

Guided surface-to-air missile (SAM) systems were developed during World War II and began to make their presence felt in the 1950s. In response, electronic countermeasures (ECM) and flying tactics were developed to overcome them. They proved to be quite successful provided that a reliable and timely threat warning was given.

The infrared-seeking missile threat

Analysis of aircraft losses due to enemy action since the 1960s shows that at least 70% of all losses were attributed to passive heat seeking i.e. Infrared (IR) guided missiles[ citation needed ]. This might be surprising given that radar guided SAM systems have longer engagement ranges, are faster, have higher maneuvering potential, carry larger warheads and are equipped with proximity fuzes.

The main reason why IR guided missiles were so effective was that it took much longer to develop effective warning systems against them. Most aircraft that were shot down never knew that the missiles were coming. Radar warning receivers on the other hand already proved their effectiveness by the early 1970s which considerably improved the survival rate of aircraft against radar threats.

The first air-to-air IR missiles appeared in the 1950s. The technology allowed more compact missile designs and made it possible to develop IR man-portable air-defense systems (MANPADS) i.e. shoulder-launched missiles, which became operational by the 1960s.

IR MANPADS are relatively cheap, quite robust, easy to operate and difficult to detect. They also do not require the infrastructure often associated with radar-guided SAM deployments, which often reveals their presence.

Vast quantities of MANPADS have been manufactured (as many as 700,000 produced since 1970 [1] ). Large numbers proliferated during the Cold War and immediate post Cold War era. Substantial quantities are available and affordable on the black market and have found their way into the hands of "non state" organizations or the so-called "asymmetric" threat. (An estimate by Jane's Intelligence Review of Feb 2003 puts this number as high as 150 000 [2] ). An article "Proliferation of MANPADS and the Threat to Civil Aviation" of August 13, 2003 by Jane's Terrorism and Insurgency Centre estimates that the black market price of MANPADS like the SA-7 could be as low as $5,000. [3]

Intelligence regarding the whereabouts of MANPADS, especially in the hands of "non state" organizations, is usually vague and unreliable. This, in turn, makes it difficult to anticipate where and when to expect MANPADS attacks.

The 2nd- and 3rd-generation MANPADS appeared by the 1980s and further increased the performance and effectiveness of MANPADS due to advanced new seeker head technology, improved rocket motors, and aerodynamic refinements. Their performance improved in terms of lethal range, minimum launch angle, maneuvering potential and all aspect engagement angles (1st-generation MANPADS were restricted to only rear sector attacks). They also became more ECM resistant.

MANPADS therefore became even more lethal specifically against more vulnerable platforms such as helicopters, light aircraft, and commercial and military transport aircraft (during approaches and departures). The slower speed of these platforms forces them to spend more time within the kill zones of MANPADS compared to high performance fighter and strike aircraft.

At least 35 MANPADS attacks on civilian aircraft are on record. Twenty-four were shot down killing about 500 people in the process.

Missile approach warning (MAW) system requirements

Protecting aircraft against IR guided missiles depends in most cases firstly on reliable detection and warning of missiles and secondly on applying effective ECM.

An exception to this are omni-directional IR jammers which do not make use of missile warning at all, as they simply radiate modulated IR energy for as long as they are switched on. These jammers have been around since the 1970s and when the correct jamming modulation techniques were applied, were reasonably effective against 1st-generation amplitude-modulated MANPADS, which operated in the near-IR band (1 to 2 micrometres (μm)). The arrival of 2nd- and 3rd-generation MANPADS changed that. They operate in the mid-IR band (3 to 5 μm) and use more advanced modulation techniques (for example frequency modulation). Instead of jamming these missiles, the omni-directional IR jammer became a source for the missiles to home in.

Functional requirements

Providing timely warning against IR MANPADS is a challenge. They give no warning of their presence prior to launch, they do not rely on active IR, radar guidance or a laser designator, which would possibly emit a detectable radiation. They are typically fire-and-forget and can lock on and engage a target, speed to the target and destroy it in seconds. They have a small but visible radar signature and also a propellant which burns – depending on the platform, typically for a very short duration.

MANPADS are relatively short-range weapons, typically up to about five kilometers with the heart of the kill envelope one to three kilometers. They therefore allow very little margin for error to effectively counter them as the time to impact (TTI) on a target at one kilometer, is only about three seconds. The TTI for targets at three and five kilometers is also relatively short – only seven to a little over eleven seconds respectively.

The MAW must provide reliable and timely warning to allow appropriate counter measure responses. Near 100% probability of warning (POW) and very fast reaction times to counter nearby missile launches (in the order of one second) are essential.

Air crew will rely on the system only if they have high confidence in it. The MAW must also have sufficiently low false alarm rates (FAR), even when illuminated by multiple sources (which may include threats) from different directions.

Quick response times and low FAR are inherently conflicting requirements. An acceptable solution requires a balanced approach to provide the most successful end result without compromising the POW. Since a longer time-to-impact (TTI) warning is almost invariably desirable, this leads to the conclusion that there is something like a too-low FAR: all warning systems gather data, and then make decisions when some confidence level is reached. False alarms represent decision errors, which (assuming optimal processing) can be reduced only by gathering more information, which means taking more time, inevitably resulting in a reduced time-to-impact. Most users would tolerate an increased FAR (up to some point where it starts limiting operations) instead of a reduced TTI, because their probability of survival depends fairly directly on the TTI, which represents the time in which countermeasures can be deployed.

Accurate azimuth and elevation angle of attack (AOA) information can be another very important requirement. Directional IR counter measures (DIRCM) systems depend on MAW systems for accurate enough initial pointing (about two degrees) to ensure that the DIRCM acquires and engages incoming missiles timely and successfully.

Accurate AOA is also important in deciding the dispensing direction of the counter measure decoys (flares). It is vital to avoid the situation where the platform and the dispensed decoys both remain within the instantaneous field of view (IFoV) of incoming missiles. In situations like that missiles could very well, once they pass the decoys, still hit the platform. This is of particular importance where separation between the decoys and the platform takes too long as is the case with slow flying aircraft.

Accurate AOA is further important where the platform should preferably maneuver when dispensing decoys to increase the miss distance. This is more applicable to fast jets where their high speed tends to negate the separation caused by the decoy's ejection velocity. A turn towards approaching missiles to establish/increase the angle between the decoy and the platform is especially important in cases where a missile approaches from the rear between the five or seven 'o clock sectors. If the AOA is not accurate enough, the pilot could very well turn in the wrong direction and set himself up for the situation as described above.

The system must also be fully automated as the human reaction time in relevant cases (short range launches) is too long.

Physical requirements

Light aircraft, helicopters, and fighters usually have limited space and mass capacity for additional equipment. The system may also cause adverse aerodynamic drag which demands minimal physical size and number of boxes. The power consumption must further be kept within the capacity of the platform's electrical system.

Human-machine interface (HMI) requirements

Integrated display and control functions are desirable to avoid duplication on instrument panels where space is limited. If a platform is equipped with both radar and missile warning systems, the HMI should display both threats clearly and unambiguously.

The integrated HMI must also indicate the system's operating status, serviceability status, mode of operation, remaining decoy quantities etc. Separate control panels are justified only for safety of flight purposes such as ECM on/off and decoy jettison functions.

Cost considerations

Procuring electronic warfare (EW) self-protection systems has direct and indirect cost implications.

Direct costs involve the initial price of the system, spare parts as well as test equipment to ensure that the performance and availability of the systems is maintained throughout their entire life cycle.

Installing and integrating EW systems on aircraft is another direct cost

Indirect cost on the other hand involves degradation of the aircraft's performance as a result of having the system on-board which in turn impacts negatively on the operating cost of the aircraft.

The lowest initial price of a system does therefore not necessarily offer the best solution as all the factors needs to be considered. The overall cost effectiveness of systems i.e. price versus performance is more important in deciding which system to select.

Types of MAW systems

Three different technologies have been used for MAW systems, i.e. systems based on: Pulse-Doppler radar, Infrared, and Ultraviolet. Each technology has its advantages and disadvantages which can be summarized as follows:

Pulse-Doppler–based MAW

Advantages
Disadvantages

Infrared-based MAW

Advantages
Disadvantages

Ultraviolet-based MWS

Advantages
Disadvantages

Implementations of MAW systems

Current available MAW systems as well as those under development, represent all three types of technologies. Each technology has strong and weak points and none provide a perfect solution.

Pulse-Doppler radar-based

France
Israel
Japan
Russia
UK
UK and Italy
US

Infrared-based

France
Germany
Germany and France
India
Israel
Italy
Russia
Türkiye
UK
US
US and Israel

Ultraviolet-based

Germany
India
Israel
Russia
Sweden/South Africa
Türkiye
US

See also

Related Research Articles

<span class="mw-page-title-main">Active electronically scanned array</span> Type of phased array radar

An active electronically scanned array (AESA) is a type of phased array antenna, which is a computer-controlled antenna array in which the beam of radio waves can be electronically steered to point in different directions without moving the antenna. In the AESA, each antenna element is connected to a small solid-state transmit/receive module (TRM) under the control of a computer, which performs the functions of a transmitter and/or receiver for the antenna. This contrasts with a passive electronically scanned array (PESA), in which all the antenna elements are connected to a single transmitter and/or receiver through phase shifters under the control of the computer. AESA's main use is in radar, and these are known as active phased array radar (APAR).

<span class="mw-page-title-main">Electronic countermeasure</span> Electronic device for deceiving detection systems

An electronic countermeasure (ECM) is an electrical or electronic device designed to trick or deceive radar, sonar, or other detection systems, like infrared (IR) or lasers. It may be used both offensively and defensively to deny targeting information to an enemy. The system may make many separate targets appear to the enemy, or make the real target appear to disappear or move about randomly. It is used effectively to protect aircraft from guided missiles. Most air forces use ECM to protect their aircraft from attack. It has also been deployed by military ships and recently on some advanced tanks to fool laser/IR guided missiles. It is frequently coupled with stealth advances so that the ECM systems have an easier job. Offensive ECM often takes the form of jamming. Self-protecting (defensive) ECM includes using blip enhancement and jamming of missile terminal homers.

<span class="mw-page-title-main">Directional Infrared Counter Measures</span> System to protect aircraft from heat seeking portable missiles

Directional Infrared Counter Measures (DIRCM) are a class of anti-missile systems produced to protect aircraft from infrared homing missiles, primarily MANPADS and similar simple systems.

<span class="mw-page-title-main">Man-portable air-defense system</span> Portable surface-to-air missile weapons

Man-portable air-defense systems are portable surface-to-air missiles. They are guided weapons and are a threat to low-flying aircraft, especially helicopters.

Northrop Grumman Electronic Systems (NGES) was a business segment of Northrop Grumman from 1996 to 2015 until a reorganization on January 1, 2016 merged other Northrop Grumman businesses into NGES to form a new segment called Mission Systems. NGES had originally been created by Northrop Grumman's acquisition of Westinghouse Electronic Systems Group in 1996. The Electronic Systems sector was a designer, developer, and manufacturer of a wide variety of advanced defense electronics and systems. The division had 120 locations worldwide, including 72 international offices, and approximately 24,000 employees; accounting for 20% of company sales in 2005.

The AN/ALR-67 radar warning receiver is designed to warn an aircraft's crew of potentially hostile radar activity. It is an airborne threat warning and countermeasures control system built to be successor to the United States Navy's AN/ALR-45. Northrop Grumman Corporation's Electronic Systems sector was the main contractor for the AN/ALR-67(V) and (V)2. Raytheon Electronic Warfare Systems was the main contractor for the AN/ALR-67(V)3.

<span class="mw-page-title-main">Infrared countermeasure</span> Device designed to protect aircraft from infrared homing missiles

An infrared countermeasure (IRCM) is a device designed to protect aircraft from infrared homing missiles by confusing the missiles' infrared guidance system so that they miss their target. Heat-seeking missiles were responsible for about 80% of air losses in Operation Desert Storm. The most common method of infrared countermeasure is deploying flares, as the heat produced by the flares creates hundreds of targets for the missile.

<span class="mw-page-title-main">AN/ALQ-144</span> Military aircraft infrared guided missile countermeasures system

The AN/ALQ-144, AN/ALQ-147, and AN/ALQ-157 are US infrared guided missile countermeasure devices (IRCM). They were developed by Sanders Associates in the 1970s to counter the threat of infrared guided surface-to-air missiles like the 9K32 Strela-2. While decoy flares were effective at jamming first generation infra-red guided missiles, each flare was only effective for a short period. If an aircraft needed to loiter over a high risk area or was flying slowly, it would require a large number of flares to decoy any missile fired at it. The IRCM provided constant protection against infra-red guided missiles.

Civil Aircraft Missile Protection System (CAMPS) is an infrared countermeasure against infrared-homed anti-aircraft missiles, specifically designed to defend civilian aircraft flying under 15,000 feet (4,600 m) against MANPADS.

Flight Guard is an Elta Systems Ltd's brand name for a family of airborne systems for protecting civilian aircraft against man-portable air-defense systems.

<span class="mw-page-title-main">Northrop Grumman Guardian</span>

The Northrop Grumman Guardian is a passive anti-missile countermeasure system designed specifically to protect commercial airliners from shoulder-launched missiles, using directed infrared countermeasures (DIRCM) technology.

The Combat Aircraft Systems Development & Integration Centre (CASDIC) is a laboratory of the Indian Defence Research and Development Organisation (DRDO). Located in Bangalore, Karnataka, India, It is one of the two DRDO laboratories involved in the research and development of airborne electronic warfare and mission avionics systems.

The Northrop Grumman Brilliant Anti-Tank (BAT) is a United States submunition round dispensed from a missile. It is capable of independently identifying and attacking armored vehicles. The BAT uses acoustic sensors to identify its intended targets, and an infrared homing (IR) terminal seeker to image and aim at the attack target.

Project CHLOE is a research and development program of the Department of Homeland Security (DHS) to explore technology-based unmanned aerial vehicle (UAV) mounted defenses for airports and airliners against the threat of infrared man-portable anti-aircraft missiles. The project's name refers to the character Chloe O'Brian on the television show 24, which is Former Homeland Security Secretary Michael Chertoff's favorite show.

The AN/ALQ-135 is an electronic countermeasure (ECM) jamming system produced by Northrop Grumman for the Tactical Electronic Warfare Suite (TEWS) on F-15 Eagle and F-15E Strike Eagle aircraft. The system can jam and track multiple anti-aircraft missiles in addition to other threats. During the Gulf War, the AN/ALQ-135 logged more than 6,600 hours of combat, yet no aircraft were lost to a threat the system protects against.

The AN/AAR-47 Missile Warning System is a Missile Approach Warning system used on slow moving aircraft such as helicopters and military transport aircraft to notify the pilot of threats and to trigger the aircraft's countermeasures systems. Its main users are the U.S. Army, Navy and Air Force, but is also operated by other countries. Originally developed by Loral, and later dual-source procured from Loral Infrared & Imaging Systems and Honeywell Electro-Optics Div., both in Lexington, MA, it has been a product of Alliant Techsystems (ATK) since 2002. 100 to 300 sets have been manufactured per annum.

CIRCM, the Common Infrared Countermeasures program, is a United States Army initiative intended to develop a lightweight, low-cost and modular laser-based infrared protection system for U.S. helicopters and light fixed-wing aircraft. The technology will primarily provide defense against shoulder-fired, heat-seeking missiles, or MANPADS. The program is being developed to replace older suites such as the Advanced Threat Infrared Countermeasures (ATIRCM).

<span class="mw-page-title-main">AN/ALQ-218</span> Military aircraft passive radar warning receiver (RWR) system

The AN/ALQ-218 is an American airborne electronic warfare radar warning receiver (RWR) system, found on Grumman/Northrop Grumman EA-6B Prowler and Boeing EA-18G Growler aircraft.

<span class="mw-page-title-main">Praetorian DASS</span> Military airplane defensive hardware and software

The EuroDASS Praetorian DASS is an integral part of Eurofighter Typhoon defensive Aid Sub-System (DASS) providing threat assessment, aircraft protection and support measures in extremely hostile and severe environments. As the DASS is fully integrated, it does not require additional pods that take up weapon stations or would influence the aircraft's aerodynamic performance. In addition the modular nature of the DASS simplifies future upgrades and allows each partner nation or export customer the option to tailor the DASS to their individual needs.

References

  1. ↑ Transnational Threats Update, vol. 1, 2003
  2. ↑ http://www.janes.com/extract/jir2003/jir00523.html . Retrieved 31 January 2022.{{cite web}}: Missing or empty |title= (help)
  3. ↑ "Proliferation of MANPADS and the threat to civil aviation". California Aviation Alliance. 13 August 2003. Archived from the original on 24 July 2018. Retrieved 31 January 2022.
  4. ↑ "Missile Approach Warner and Advanced Missile Detection System, PVS2000 :: Rochester Avionic Archives". rochesteravionicarchives.co.uk. Retrieved 2023-05-01.
  5. ↑ "Missile Approach Warner" (PDF). Rochester Avionics Archives. 1993. Retrieved 2024-03-27.
  6. ↑ "Le premier Rafale de la "tranche 4" débarque dans les forces". Air et Cosmos. 23 September 2013. Retrieved 2020-08-04.
  7. ↑ "Dual Colour Missile Approach Warning System (DCMAWS) for Fighter Aircraft | Defence Research and Development Organisation - DRDO, Ministry of Defence, Government of India". www.drdo.gov.in. Retrieved 2023-08-06.
  8. ↑ www.ETGovernment.com. "DRDO to showcase technologies, innovations and capabilities at Aero India 2021 - ET Government". ETGovernment.com. Retrieved 2023-08-06.
  9. ↑ "CAG flags DRDO declaring 20 mission mode projects 'successful' despite not achieving objectives". www.thehindubusinessline.com. 2022-12-22. Retrieved 2023-08-06.
  10. ↑ "MAIR". Leonardo. Retrieved 7 April 2023.
  11. ↑ "Ancile".
  12. ↑ https://x.com/aselsan/status/1822970090633015519 [ bare URL ]
  13. ↑ "MILDS AN/AAR-60 Missile Warning System." EADS North America, Retrieved 18 July 2013.
  14. ↑ "DRDO-built radar tech to power IAF's Airbus aircraft". The Times of India. 2021-11-26. ISSN   0971-8257 . Retrieved 2023-08-06.
  15. ↑ "MAW 300 [ permanent dead link ]" Saab Avitronics
  16. ↑ "İri̇s-100".
  17. ↑ "Northrop Grumman to Install AN/AAR-54(V) Warning Systems on Royal Netherlands Helicopters". Northrop Grumman Newsroom. 16 June 2001. Archived from the original on 3 July 2022. Retrieved 3 July 2022.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.