CRN 91 Naval Gun

The  Close Range Naval-91 is a naval version of the Medak 30mm automatic gun installed on the Sarath Infantry fighting vehicle, a variant of the Russian (originally Soviet) BMP-2 manufactured in India under license by the Ordnance Factory Medak. The Medak gun itself is based on the Russian Shipunov 2A42 30 mm automatic cannon.

The CRN-91 Naval gun is gyro stabilized and is directed by electro-optic fire control system (FCS) of Bharat Electronic LTD make for day and night use, mounted on an improvised cupola. It can also be remotely operated.

The CRN-91 Naval gun is not a sophisticated weapon but its operational cost is very low. It is suited for vessels primarily designed for peacetime patrolling and policing, particularly for anti-insurgency, anti-smuggling, anti-pirate and maritime surveillance of exclusive economic zones (EEZ).

It has been installed on many small warships such as:
 * Car Nicobar class fast attack craft
 * Kumbhir class landing ship
 * Shardul class landing ship
 * Trinkat class patrol vessel
 * Bangaram class patrol vessel
 * Rani Abbakka Class
 * ABG Class Pollution Control Vessel
 * Rajshree class inshore patrol vessel

Combat use
An Indian fishing trawler was hijacked by ltte. It was spotted by fishermen in Maldivian waters on the night of May 17, 2007, and they tried to chase it away. But there was firing from the trawler and the Maldives Coastguard was alerted. Immediately, Maldives moved the Huravee that engaged the boat for over 10 hours before sinking it at 8.30 am on May 18, 2007.

The renamed Huravee is a former Indian Coast Guard ship given to the Maldives - its former name was INS Tillanchang. It is a Trinkat class patrol vessel equipped with a CRN-91 30 mm Automatic gun.

Battle off Minicoy Island
In January 2011, as a part of Operation Island Watch, INS Cankarso and INS Kalpeni were deployed on anti-piracy patrol to the west of the Lakshadweep archipelago. On January 28, INS Cankarso responded to a mayday call from a container ship. Upon reaching the site, she saw Somali pirate skiffs being hoisted aboard a hijacked Thai fishing trawler, Prantalay 14 which was being used as a pirate mother ship.

INS Cankarso ordered the pirated ship to stop for inspection. The pirates on board fired on Cankarso as they tried to flee west towards Somalia. Cankarso returned the fire, which hit some of the fuel drums stored on Prantalay 14's deck for refueling the skiffs. The mother ship was set ablaze and sank as Kalpeni and Indian Coast Guard patrol vessel ICGS Sankalp reached the site. 15 pirates were arrested, and the 20 crew of the fishing trawler were all rescued unharmed.

In another operation on 13 March 2011, an Indian Navy patrol aircraft spotted the Mozambique-registered fishing vessel Vega 5 when responding to another vessel reporting a pirate attack. Beira-based Vega 5, owned by Spanish company Pescamar Lda, had been captured on 27 December 2010 by pirates who were demanding USD 1.8 million in ransom.[15] INS Kalpeni intercepted the pirated ship about 1,100 kilometres (680 mi) off Kochi on India's west coast. A fire broke out on the vessel when Kalpeni returned fire after being fired upon by the pirates. 61 pirates were rescued and arrested after they jumped into the Arabian Sea to escape the fire. The crew of Kalpeni put out the fire on board the Vega 5, rescued her 13 crew members and escorted her to Mumbai. Rocket-propelled grenades and over 80 assault rifles were recovered from the pirates.

INS Kalpeni and INS Cankarso are Car Nicobar class fast attack craft equipped with a CRN-91 30 mm Automatic gun.

Specification
Rate of Fire Range Sight Type : BPK 2-42 Day system Night system
 * Caliber : 30mm
 * Diameter : 2700mm
 * Height : 2100mm
 * Gun feed : Double belt separate
 * Sustained : 200 to 300 rounds per min
 * Maximum : 550 rounds per min
 * Armour piercing tracer projectile : 2000m
 * HE incendiary and fragmentation tracer projectile : 4000m
 * Magnification : 6X
 * Field of view at least : 10�
 * Periscope height : 221mm
 * Magnification at least : 5.5X
 * Field of view at least : 6�40'
 * Periscope height : 248mm