Indigenous IRST sensors can help Indian fighters detect Stealth aircrafts
India has decided to design and develop a long-range dual-band infrared imaging search and track system (IRST) which will strengthen the capabilities of the Su-30MKI in detecting ultra-stealthy aircraft like the F-22 and Chengdu J-20 possessed by its adversaries. Only last year, China operationalized the J-20 fighter jets which are made up of radar-absorbing materials that are supposed to make it hard to detect at long ranges.
The OLS-36Sh-01 i currently used in the Su-30MKI and the Su-30MKM. It incorporates a scanning thermal detector, laser rangefinder and integrated system monitoring.
The system performs passive search, detection and tracking of airborne targets at all aspects and against ground clutter, clouds and reflective water surfaces, by day and night and in the presence of IR countermeasures. The laser rangefinder provides accurate range measurement for the employment of short-range Air-to-Air Missiles (AAMs) and against ground targets. A detection range of up to 90 km is suggested (large thermal signatures such as afterburners against a cooler background), while the laser rangerfinder is effective to 3.5 km
IRST looks for temperature differences using liquid hydrogen or nitrogen to cool the sensor to extremely low temperatures which provides a contrast to the outside. Then it relies on the fact that the air is very cold (at altitude) and any fighter airframe moving through the air at several hundred knots, or particularly supersonic, heats up a lot so temperature difference is huge.IRST is hugely affected by weather. Humid parts of the world are inhospitable, and the thermal imaging works better at night when the skies are cooler.
IRST systems are heat-seeking sensors, just like forward looking infrared (FLIR) pods, but they go a few steps further by enabling users to search and track individual airborne targets.Since IRST sensors are simply ‘receiving’ an emitting heat signal, they are “passive” sensors. In other words, they do not emit signals of their own (unlike radars, which transmit radio waves). This enables the tracking fighter to avoid alerting the target’s RWR [radar warning receiver], which is designed to react to active radar signals. In a within visual range dogfight, an IRST system can enable the user to possess an enhanced level of situational awareness of the combat zone without having to switch-on the radar, thus avoiding the risk of being an “exposed” target.
“The Defense Acquisition Council (DAC) accorded approval for undertaking design and development of the Long Range Dual Band Infrared Imaging Search and Track System (IRST) for SU-30 MKI aircraft under the ‘Make II’ sub-category and subsequently, for procurement of at least 100 IRSTs under ‘Buy (Indian-IDDM)’ category. The system will be able to operate in day and night conditions and will substantially enhance the capabilities of the aircraft,” a statement issued by Indian defense ministry reads.
The Indian defense ministry wants at least 40% domestically-produced content in the system which will be manufactured in any Indian facility. The system will be integrated into India’s frontline aircraft without making any structural changes.
Last year, the Indian Air Force (IAF) while specifying its technical requirements, had put up 30 questions before the prospective vendors.
“Will be equipment be single dome configuration? Will the equipment have stowing capability? Can the equipment be matched with aircraft mission computer software? What are the ICD requirements of the equipment to ensure full exploitation of capabilities of the equipment?” the IAF had asked.
The IRST system is a crucial part of the advanced fifth-generation aircraft as it plays a critical role in detecting heat sinking missiles and locate and destroy enemy targets in radar denied environment.
In all, the Defense Acquisition Council (DAC), chaired by Defense Minister Nirmala Sitharaman, on Monday accorded approval for the procurement of equipment for the defense forces valued at over one billion dollars. The DAC also approved procurement of thermal imaging (TI) night sights for the rocket launcher used by the Indian Army and the IAF from local vendors. The TI sight for 84mm rocket launcher will be used by troops in operations to facilitate accurate and continuous engagement of moving and static enemy targets and destruction of field fortifications (bunkers) during hours of complete darkness.
“The sight will enable our troops to detect and recognize enemy tanks and soldiers’ movement during the night and engage them with greater efficiency. Furthermore, the effect of camouflage and concealment will be drastically reduced as rocket launcher detachments will be able to ascertain the location of the enemy taking cover behind foliage and thin-walled constructions with greater ease,” the defense ministry statement read.
Source:- Sputnik News