The Indian armed forces already have in service the indigenously designed and manufactured Nishant and the Israeli Heron and Searcher I & II UAVs. General Dalbir Singh Suhag, the former COAS, had said during an interview in January 2015, “UAVs would play a vital role in future battles and there is a requirement to enhance the Indian Army holdings.”
UAVs are low-cost, low-risk, high-payoff intelligence, surveillance and reconnaissance (ISR) and target acquisition (TA) systems. UAVs can be deployed quickly to cover vast areas and, hence, enhance responsiveness. The employment of UAVs improves situational awareness, helps to increase the operational tempo and reduces the sensor-to-shooter time lag. When employed in conjunction with other sensors, UAVs assist in confirming or negating the efficacy of informationgathered and, thus, qualitatively improve the intelligence available to commanders.
While UAVs have several disadvantages such as vulnerability to enemy fire and interception and limitations of communications, they can be employed flexibly and provide unique capabilities to all the Services. While some operational needs are common, others are specific to individual Services.
Reconnaissance, Surveillance and Target Acquisition (RSTA) Requirements of the Services
A large number of the RSTA requirements that can be fulfilled by UAVs are common to all the Services, though with minor variations in the methodology of use. The major common needs of the Services are as under:
Strategic surveillance of the nuclear capabilities, movement of nuclear warheads and materials and deployment of nuclear assets of adversaries, particularly during war.
Detection of missile launchesduring war.
RSTA by way of photo reconnaissance, thermal/IR imaging and SAR during peace-time, the preparatory stage and during war for battlespace transparency.
Target designation for ground-, air- and sea-launched PGMs.
Suppression of enemy air defence (SEAD).
Post-strike damage assessment.
Signals and electronic intelligence (Sigint and ELINT).
Electronic warfare (ECM and ECCM).
Information warfare including psychological and propaganda operations
Communications relay platform to extend the range of VHF and UHF communications
NBC detection, early warning and monitoring of contamination (nature and level of nuclear radiation, collection of air samples).
Digital mapping.
Meteorology
Combat Drones
Another emerging requirement is that of unmanned combat air vehicles (UCAVs) to deliver PGMs to destroy selected targets. UCAVs have come of age and have proved their efficacy in recent wars fought in Afghanistan and West Asia. These new weapons platforms have enormous potential to be ‘cued on’ to targets that have been identified and selected for destruction or to act as stand-alone hunter-killers in a battlespace that is teeming with targets, e.g. during an enemy offensive launched with mechanised forces in the plains. The weaponry that UCAVs need to carry and the on-board sensor suite that is necessary to locate targets and guide PGMs on to them, need separate analysis and are not discussed here. It has been reported that the IAF is likely to soon induct the Harop UCAV of Israeli origin. It is a combination of a UAV and a missile and is disposable. Also, the DRDO is developing the AURA (autonomous unmanned research aircraft) UCAV for the IAF.
Future UAV Technologies
Sensor suites are the most important subsystem of a modern UAV and account for one-third to half its cost. The selection of sensors is extremely important, as these must provide information and data in an electronic form that is compliant with the network centricity requirements of the Services. Ideally, data standards should be the same in all the Services so that the inputs provided by the surveillance devices of one Service can be used without any problem by the other Services.However, while the Services are working on achieving compatibility, in the short-term it may be adequate to share information and data after due sifting rather than automatically.
The most common user need, particularly of the Army, is to be able to see a real-time picture of the battlefield during day light conditions. Hence, real-time streaming video is a major requirement. Since it requires a large bandwidth, video imposes severe constraints on the communications suite that a UAV can carry. Modern satellites are providing photos of one metre resolution and photos of up to 30 cm resolution can be procured commercially today, though with a small time lag. Specially designed military satellites are capable of providing a still higher resolution. Hence, it would be justifiable for the users to demand day light photos of equally good resolution from UAVs that fly at much lower altitudes. Photos of such high resolutions will enable users to clearly identify even small military targets, prioritise them for engagement and adjust artillery fire or destroy them with PGMs. The electro-optical/ thermal imaging/ infra-red (EO/TI/IR) sensors available today can meet this demand.
Communications are the key to UAV operations. Failsafe communications are required not only to provide operator instructions to the UAV but also to downlink information and data collected by the UAV and for the UAV to act as a communications relay platform when necessary. Secured, reliable VHF and UHF radio links are required for command and control. Larger bandwidths are necessary for data download. Advances in satellite communications technology have brought UAVs into the ambit of satellite control and reduced the need for relay stations to optimally exploit their range. For naval UAVs on long endurance offshore missions, satellite links are inescapable. Command and control communications also need to be provided with ECCM capabilities so that the UAVs can be given instructions even under enemy jamming. Sigint and ELINT missions and active EW missions are rapidly becoming significant roles for UAVs as weight and power limitations are being gradually overcome. The existing indigenous EW capability needs to be enhanced further and adapted for use on UAVs.
UAVs must be able to provide an accurate location of enemy targets (tanks, gun positions, weapon emplacements, bumpers and pill boxes, ATCs, communications centres, enemy ships etc.) or points of interest (choke points, bridges, artificial obstacles, oil slicks etc.). For the purposes of targeting by artillery fire, the location should be accurate ideally to within five metres. Even with GPS, especially non-military use GPS, such accuracies may not be achieved.
In the air defence environment prevailing in modern wars, the survivability of UAVs is a key requirement. The technologies necessary to enhance survivability include low radar signature, radar warning receivers, chaff dispensers, ECCM suites to ensure that communications with the UAV are not disrupted, low acoustic signature of the engine and, where possible, radar absorbing paints. These requirements will undoubtedly burden designers with the need to strike a fine balance between the size, shape and weight of the airframe and the payload that can be carried.