The AN/ALQ-144, AN/ALQ-147, and AN/ALQ-157 are US infra-red guided missile countermeasure devices (IRCM). They were developed by Sanders Associates in the 1970s to counter the threat of infra-red 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 (as helicopters do), 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.
The ALQ-144 and ALQ-147 were first delivered to the US military in 1981. Currently there are over 3,500 in use with the US military, and a total of 6,000 in use by nineteen countries globally. Seven hundred ALQ-157 systems are currently in service.[citation needed]
Both systems consist of a heated silicon carbide block that radiates a large amount of infra-red energy. It is surrounded by a large cylindrical mechanical shutter that modulates the infra-red output, producing a pulsing pattern. Early infrared guided missiles used a rotating reticle. When a target was not on the sensor's centerline, it would produce a pulse as the reticle swept over the target. When the target was on the sensor's centerline, the sensor would produce a constant signal. This constant signal was required by the early missiles to produce a "lock on" that would allow a launch.
The ALQ-144 and 147 IRCM produced a pattern of pulses that was approximately synchronized with the rotation rate of these reticles. Before launch this would prevent the missile actually locking onto the target, preventing the operator from firing the missile. After launch this would cause the missile to think that the target was off to one side and cause the missile to steer away from the aircraft carrying the IRCM.
The introduction of rosette and "staring" scanning techniques in second generation missiles reduced the effectiveness of the ALQ-144 and 147; later upgrades restored the effectiveness of the jammers.
The ALQ-144A was rushed into US service in time for the 1991 Gulf War, as Iraq had stocks of 9K34 Strela-3 and 9K38 missiles, against which the ALQ-144 was only partially effective. By the time the war started, two-thirds of the AH-64 Apaches in the persian Gulf had been upgraded to ALQ-144A standard. The only AH-64 Apache lost to an infra-red guided missile was hit by a 9K34 Strela-3 missile; the helicopter in question was one of the few that had not been upgraded.[1]
The ALQ-144's distinctive appearance has earned it the nicknames "disco light", "disco ball", "mirror-ball" or "R2-D2".
ALQ-157edit
Produced by Loral, the system consists of two emitters, each one covering one side of a large aircraft. The system is microprocessor controlled and has five pre-set jamming patterns.
Specificationsedit
Designation
Entered service
Output
Weight
Platforms
ALQ-144
1980
1.7 kW
12.5 kg
ALQ-147
1980
?
?
ALQ-157
1984
2 kW (later 4 kW)
99 kg
Variantsedit
ALQ-144 electrically powered IRCM
ALQ-144A upgraded system to deal with more recent generations of IR guided missiles.
ALQ-144A(V)1 – Standard in helicopter jammer
ALQ-144A(V)3 – Added RFCM on/off switch
ALQ-144A(V)5 – Increased protection with a dual phaselocked transmitters and jam code selector switch on the operator control unit
ALQ-144A+ – Increased protection with the higher power
ALQ-144A+(5) – Increased protection plus with the dual phaselocked ALQ-144A+ transmitter
ALQ-147 mounted in a modified 150 US gallon (570 liter) drop tank, it is a fuel powered IRCM.
ALQ-147A upgraded system to deal with more recent generations of IR guided missiles.
ALQ-157 large aircraft version of the system fitted to CH-47 Chinook and C-130 Hercules aircraft, consists of two units, each giving semi-circular coverage.
ALQ-157M upgraded system to deal with more recent generations of IR guided missiles.
^Price, Alfred (2000). The History of U.S. Electronic Warfare: Volume III, Rolling Thunder Through Allied Force, 1964 to 2000. The Association of Old Crows. p. 451. ISBN0-9703794-0-4.
The Naval Institute Guide to World Naval Weapon Systems, Norman Friedman, ISBN1-55750-268-4
October 27, 2023
infra, guided, missile, countermeasure, devices, ircm, they, were, developed, sanders, associates, 1970s, counter, threat, infra, guided, surface, missiles, like, 9k32, strela, while, decoy, flares, were, effective, jamming, first, generation, infra, guided, m. The AN ALQ 144 AN ALQ 147 and AN ALQ 157 are US infra red guided missile countermeasure devices IRCM They were developed by Sanders Associates in the 1970s to counter the threat of infra red 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 as helicopters do 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 An ALQ 144 jammer mounted on an OV 10 Bronco The ALQ 144 and ALQ 147 were first delivered to the US military in 1981 Currently there are over 3 500 in use with the US military and a total of 6 000 in use by nineteen countries globally Seven hundred ALQ 157 systems are currently in service citation needed Contents 1 ALQ 144 ALQ 147 2 ALQ 157 3 Specifications 4 Variants 5 See also 5 1 Related ECMs 6 ReferencesALQ 144 ALQ 147 editBoth systems consist of a heated silicon carbide block that radiates a large amount of infra red energy It is surrounded by a large cylindrical mechanical shutter that modulates the infra red output producing a pulsing pattern Early infrared guided missiles used a rotating reticle When a target was not on the sensor s centerline it would produce a pulse as the reticle swept over the target When the target was on the sensor s centerline the sensor would produce a constant signal This constant signal was required by the early missiles to produce a lock on that would allow a launch The ALQ 144 and 147 IRCM produced a pattern of pulses that was approximately synchronized with the rotation rate of these reticles Before launch this would prevent the missile actually locking onto the target preventing the operator from firing the missile After launch this would cause the missile to think that the target was off to one side and cause the missile to steer away from the aircraft carrying the IRCM The introduction of rosette and staring scanning techniques in second generation missiles reduced the effectiveness of the ALQ 144 and 147 later upgrades restored the effectiveness of the jammers The ALQ 144A was rushed into US service in time for the 1991 Gulf War as Iraq had stocks of 9K34 Strela 3 and 9K38 missiles against which the ALQ 144 was only partially effective By the time the war started two thirds of the AH 64 Apaches in the persian Gulf had been upgraded to ALQ 144A standard The only AH 64 Apache lost to an infra red guided missile was hit by a 9K34 Strela 3 missile the helicopter in question was one of the few that had not been upgraded 1 The ALQ 144 s distinctive appearance has earned it the nicknames disco light disco ball mirror ball or R2 D2 ALQ 157 editProduced by Loral the system consists of two emitters each one covering one side of a large aircraft The system is microprocessor controlled and has five pre set jamming patterns Specifications editDesignation Entered service Output Weight PlatformsALQ 144 1980 1 7 kW 12 5 kgALQ 147 1980 ALQ 157 1984 2 kW later 4 kW 99 kgVariants editALQ 144 electrically powered IRCM ALQ 144A upgraded system to deal with more recent generations of IR guided missiles ALQ 144A V 1 Standard in helicopter jammer ALQ 144A V 3 Added RFCM on off switch ALQ 144A V 5 Increased protection with a dual phaselocked transmitters and jam code selector switch on the operator control unit ALQ 144A Increased protection with the higher power ALQ 144A 5 Increased protection plus with the dual phaselocked ALQ 144A transmitter ALQ 147 mounted in a modified 150 US gallon 570 liter drop tank it is a fuel powered IRCM ALQ 147A upgraded system to deal with more recent generations of IR guided missiles ALQ 157 large aircraft version of the system fitted to CH 47 Chinook and C 130 Hercules aircraft consists of two units each giving semi circular coverage ALQ 157M upgraded system to deal with more recent generations of IR guided missiles See also editBoeing EA 18G Growler CAMPS Civil Aircraft Missile Protection System Electronic countermeasures Electronic warfare Northrop Grumman EA 6B ProwlerRelated ECMs edit AN ALQ 99 AN ALQ 128References edit Price Alfred 2000 The History of U S Electronic Warfare Volume III Rolling Thunder Through Allied Force 1964 to 2000 The Association of Old Crows p 451 ISBN 0 9703794 0 4 War in the Fourth Dimension Dr Alfred Price ISBN 1 85367 471 0 The Naval Institute Guide to World Naval Weapon Systems Norman Friedman ISBN 1 55750 268 4 Retrieved from https en wikipedia org w index php title AN ALQ 144 amp oldid 1133483637, wikipedia, wiki, book, books, library,
