A little history-digging will be good.The event happened during 1971 war between India and Pakistan.
The Attack on Karachi
The most dramatic naval plan was drawn up by the Western Naval Command. It was decided that the main attack on Karachi harbour would be launched by tiny PT-15 missile boats instead of regular warships. There were several reasons for this decision. Regular ships without air cover would be vulnerable whereas the tiny missile boats would present difficult, fast-moving targets. Moreover, the Navy wanted to try out the missiles to see how effective they could be in real action, although this kind of use of missile boats, which were designed for coastal defence and not for long range offensive action of any kind, was highly unorthodox. At any rate, three missile boats were chosen for the mission and despatched in the dead of night from Bombay harbour.
Leading the missile boat squadron was Commodore (Retired) Babru Bahan Yadav:"The task given to us was not easy. Our ships were little more than boats and did not have the range to go all the way to Karachi on their own steam. So an oiler was placed about half-way to the target and we were able to refuel and carry on.
"As we neared their coast, we found some of their ships patrolling the area. The boat on my left was detailed to engage the contact. That boat was the first Indian warship to fire a missile in anger. Two missiles were fired and both were direct hits. It is interesting to recall that the radar contact which was on our screen slowly diminished and then suddenly disappeared. We were very jubilant at that time. Later, we found that this has been a Pakistani destroyer.
Very soon another ship was located right in front of my boat. We fired a couple of missiles as well but did not sink it. The boat on our right was ordered to attack the ship. It did so and managed to cripple it completely. We thought we had sunk it but later the Pakistanis claimed that the ship had been badly crippled and put out of action but not sunk. Anyway, as we continued, both the other boats could not keep up and had to turn back. Only Nipat, the boat I was on, could proceed towards Karachi harbour. We pressed on and fired missiles on Karachi which hit the oil installations there. The attack took place just 1 minute before midnight and we could see the flames from the oil installations lighting up the sea. It looked like Diwali (Indian festival of lights and firecrackers)."
It took a few more days for Commodore Yadav's boat to return to harbour as they had to take evasive action and ran out of fuel. In the meanwhile, the Pakistanis who were hunting for the boat put out a message that an Indian vessel had been sunk. Nipat, the only boat not accounted for at that time, was presumed sunk. But Nipat returned, thanks to the ingenuity of its engineers who managed to take out pump oil and use it to run the engines.
The Indian Navy accomplished the task assigned to it within the first few days of the war. No enemy shipping could move in or out of its harbours. Merchant ships did not dare approach Karachi. Control of the seas around both wings of Pakistan was with the Indian Navy.
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