An infrared search and track ( IRST ) system (sometimes known as infrared vision and tracking ) is a method for detecting and tracking objects that issue infrared radiation (see Infrared signature) such as jets and helicopters.
IRST is a general case of infrared forward (FLIR), that is from awareness of the all-round situation. Such systems are passive (thermographic cameras), which means they do not provide any radiation of their own, unlike radar. This gives them a hard advantage of their detection.
However, because the atmosphere weakens the infrared to some extent (though not as much as visible light) and because bad weather can attenuate it too (again, not as bad as the visible system), its range is compared to the limited radar. In range, the angular resolution is better than the radar because the wavelength is shorter.
Video Infra-red search and track
Sistem awal
The first use of the IRST system appears to be F-101 Voodoo, F-102 Delta Dagger and F-106 Delta Dart interceptor. The F-106 had an early IRST installation replaced in 1963 with the production of a retractable cradle. IRST is also incorporated into the Vought F-8 Crusader (F-8E variant) which allows passive hot passive tracking and is similar to Texas Instruments AAA-4 installed on the initial F-4 Phantom.
The F-4 Phantom has a Texas Instruments AAA-4 infrared locator under the nose of the initial F-4B and F-4C production aircraft and is not installed on the F-4-D then due to limited capabilities, but retains bulge and indeed some F-4D have IRST receivers mounted in modified form.
The F-4E eliminates the AST-AAA-4 IRST and receives an internal rifle hammer that picks up the area under the nose. F-4J which has pulse-doppler radar also eliminates the AAA-4 IRST receiver and the bulge under the nose.
IRIST's first use in Eastern countries is by Mikoyan-Gurevich MiG-23 MiG-23 used (TP-23ML) IRIST and the latest version of MiG-23 is used (26SH1) IRST. Mikoyan-Gurevich MiG-25PD is also equipped by a small IRIST under the nose.
Saab J-35F2 Draken Sweden (1965) also uses IRST, Hughes Aircraft Company N71.
Technology
It is a fairly simple system consisting of an infrared sensor with a horizontal spinning shutter in front of it. The shutter is slave-to-screen under the main interception radar display in the cockpit, any IR light falling on the sensor will produce a "pip" on the screen, in a manner similar to the B-scopes used on the initial radar.
The screen was primarily intended to allow radar operators to manually change the radar to the target's target angle, in an era when the radar system had to be "locked" by hand. These systems are considered unlimited utilities, and with the introduction of more automatic radar they disappeared from the fighter design for some time.
Maps Infra-red search and track
Later system
The IRST system reappeared on a more modern design started in 1980 with the introduction of a 2-D sensor, which provided horizontal and vertical angles. Sensitivity is also greatly improved, leading to better resolution and range. In recent years, the new system has entered the market. In 2015, Northrop Grumman introduced its OpenPod (TM) IRST pod, which uses the sensor by Leonardo.
Pengguna system IRST modern yang paling dikenal adalah:
- Ã, China
- Chengdu J-10B
- Shenyang J-11/15/16
- Chengdu J-20 (EORD-31)
- Ã, Prancis
- Dassault Rafale (Optronique secteur frontal OSF)
- Ã, Russia
- Su-27/30/35 Flanker (OLS-27/30/35)
- Mikoyan MiG-31 (8TK)
- MiG-29/35 (OLS-29/35)
- Sukhoi Su-57 (101KS-V)
- Ã, Swedia
- Saab JAS 39 Gripen E/F (Selex ES Skyward-G)
- Eurofighter Typhoon (Selex ES PIRATE)
- America Serikat
- Grumman F-14 Tomcat (AN/AAS-42 IRST)
- Boeing F-15K Slam Eagle
- Boeing F-15SA Advanced Eagle
- Boeing F-15QA Advanced Eagle
- Lockheed Martin F-16 E/F Block 60/62 (AN/AAQ-32 IFTS)
- Boeing F/A-18E/F Super Hornet (Block III)
- Lockheed Martin F-35 Lightning II AN/AAQ-37 Electro-Optical Distributed Aperture System (DAS) dengan 360 derade IRST, rudal/peringatan deten, dan kemampuan visi siang/malam, yang dirancang dan diproduus oleh Northrop Grumman Electronic Systems.
This aircraft brings the IRST system to be used as a radar replacement when circumstances require it, such as when shadowing another plane, under the control of Airborne Early Warning and Control (AWACS) aircraft, or execute ground controlled interception (GCI), where external radar is used to help vector fighter to the target and IRST is used to retrieve and track the target after the fighter is within range.
With an infrared or missile-and-miss missile, the fighter might be able to shoot up the target without having to turn on his radical device at all. Otherwise, the fighter can turn on the radar and immediately reach the key before firing if desired. Fighters can also approach within reach of the cannon and get involved that way.
Whether or not they use their radar, the IRST system can still allow them to launch a surprise attack.
The IRST system may also have an enlarged magnified optical zoom for it, to help IRST-equipped aircraft identify targets at a distance. Unlike the ordinary forward-looking infrared system, the IRST system will actually scan the space around the aircraft similar to the way in which mechanical (or even electronic) radar driving works. The exception to the scanning technique is the F-35 JSF watershed, which gazes in all directions simultaneously, and automatically detects and declares planes and missiles in all directions, with no limit on the number of targets being tracked simultaneously.
When they find one or more potential targets, they will alert the pilot and display the location of each target relative to the aircraft on the screen, such as radar. As with radar, operators can tell the IRST to track a particular desired target, once identified, or scan in a certain direction if the target is believed to be there (for example, because of advisors from AWACS or other aircraft).
The IRST system can combine laser rangefinders to provide full fire control solutions to fire cannons or launch missiles (Optronique secteur frontal). The combination of atmospheric propagation models, clear target surfaces, and target motion analysis (TMA) IRST can calculate ranges.
The United States Air Force is currently looking for an IRST system for its F-15 aircraft.
Performance
The detection range varies with
- cloud
- heights
- air temperature
- target attitudes
- target speed
The higher the altitude, the less atmospheric and less infrared radiation is absorbed - especially at longer wavelengths. The effect of friction reduction between air and aircraft does not compensate for better infrared radiation transmission. Therefore, the infrared detection range is longer at high altitudes.
At high altitude, temperatures range from -30 to -50 ° C - which provides better contrast between aircraft temperatures and background temperatures.
IRF IRIGA from Eurofighter Typhoon can detect subsonic fighters from a distance of 50 km from front and 90 km from the rear - greater value is a consequence of observing directly the engine exhaust, with an even larger increase becoming possible if the target uses afterburner.
The range at which the target can be identified with enough confidence to decide the release of the weapon is significantly lower than the detection range - the manufacturer has claimed it is about 65% of the detection range.
See also
- Electrical Optical Targeting System
- AN/AAQ-37 Electro-Optical Optical Flow Aperture System
References
Note
Quote
Bibliography
- Eden, Paul ed. The Encyclopedia of Modern Military Aircraft . London: Amber Books Ltd, 2004. ISBNÃ, 1-904687-84-9
- Kinzey, Bert. F-106 Delta Dart, in Details & amp; Scale . Fallbrook, CA: Aero Publishers, 1983. ISBNÃ, 0-8168-5027-5.
- Sweetman, Bill and Bond, Ray. The Great Airwaves of Modern Aircraft . New York, New York: Crown Publishers, 1987. ISBNÃ, 0-517-63367-1
External links
- Fraunhofer Institute IAF 2006 annual report Germany and the UK.
Source of the article : Wikipedia
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