How Indian Navy neutralize the threat of subsonic Sea Skimming missile

At first let’s understand how subsonic Cruise missile poses a threat to naval ships. Naval vessels are mostly very slow like snail compared to aircrafts & it moves on the surface of ocean slowly with long range early warning system & air defence missiles, guns & other decoy system to prevent enemy strikes.

As you know “earth is not flat” which is why the radio waves actually go upwards after 15-20km. This is how, Horizon creates problems for the naval ships to detect low flying objects from long distance.

Subsonic cruise missiles are developed to take advantage of this limitation caused by the horizon. It flys low which makes it difficult to be detected by the radars. The target ship with it’s radar only can detect the missile at the range of about 15-20km. Now the target ship can only engage the missile with quick reaction surface to air missile or CIWS.

Nowadays the missiles have evolved further. To protect itself from CIWS or short range ADS, modern cruise missiles like Russian Kalibr are supersonic & increase it’s terminal speed to mach 3. So in terminal stage the missile becomes so fast that target ship does not get enough time to activate it’s air defence.

Then Indian Navy came with a peculiar but effective idea. Indian Navy approached kamov & in 1999 Indian navy ordered ka-31 based AEW system. At that time even Russia was hesitating to Induct the system. After the deal with Indian Navy, Russians just waited to see how it would perform. Indian navy found major problems with this system. Specifically, its limited endurance/range. In response, HAL was commissioned to experiment and possibly adapt a helicopter-to-helicopter refuelling system. Also, in the Indian service, the aircraft received Abris GPS system featuring a 12-channel receiver and option to employ Differential GPS references.

The later batches featured navigational equipment for digital terrain maps, ground-proximity warning, obstacle approach warning, auto-navigation of pre-programmed routes, flight stabilization and auto homing onto and landing at the parent carrier/base and information concerning the helicopter’s tactical situation.

Finally Russian found it worthy & ordered the heli for it’s own navy.

As Ka-31 use the same airframe as Ka-27, it uses co-axially mounted contra-rotating main rotors which makes it significantly smaller in size so the helicopter can be operated from almost all the frontline ships of the Indian navy. Equipped with E-801M OKO (“EYE”) planar array radar the helicopter can easily detect enemy missiles, aircrafts, enemy helicopter or any other surface or air targets from 150+km can warn the ships about the certain threat. Equipped with 16-channel digital communication gear with range of up to 250 miles (400 km), the heli can communicate with ship from a longer distance. Not only it can warn the ship But it can also guide the Russian Shtil-1 or future Indian air defence systems such as Akash-NG if it is deployed on warships.

As the AEW flys at higher altitude & vertically it can monitor a large area and situational awareness capabilities of ships improve significantly to monitor enemy activities. This is a massive advantage for the Indian Navy.

Ka 31 can operated from all the IN platforms. All the Indian , corvettes , frigates , destroyers and also Aircraft carriers. Ka 31 can be used in surface search , Sub surface search & Air search . It can watch over a 400km radius and can guide anti ship missiles of Russian origins to the intended target till the missiles won Radar & seeker catches the target. Presence of Ka 31 along with a MH 60 on a Kolkata class destroyer equipped with Barak & BrahMos can be proved fatal for any opposition including USN. Sub hunting Kamrota class corvettes would get an extra teeth in finding out Subs of any make. Further we have about 20 of them already in operation so no more logistical arrangement or pilot traning would be required.