India’s CSL completes aircraft carrier refit
The Indian government announced that Cochin Shipyard Limited completed repair works on the Indian aircraft carrier INS Vikramaditya on November 5.
The ship spent little over a month in dry dock after the navy decided in September to dry-dock the carrier when it was at the Karwar Naval Base.
Officials said they were not sure whether the CSL was capable of performing a task as complex as this one.
“Till INS Vikramaditya docked in Cochin Shipyard and water was pumped out of the dock and we had her sitting safely, there was a real concern on whether India could do it,” Shri Rajesh Gopalakrishnan from CSL said.
The company had considerable planning & preparation to do in order to accommodate the ship that was bought from Russia in 2014. This involved administrative, logistic and technical arrangements of a large magnitude.
CSL first had to task IIT Chennai to undertake a detailed dock floor strength analysis to prove that the dock had the capacity to accommodate loads of this nature. The design of the dock blocks was done in-house thereafter by CSL to seat the Carrier in the dry-dock.
For one, INS Vikramaditya needed specially designed dock blocks made of plenty of hard as well as soft wood on which she could sit. (Shipyards typically go for a combination of concrete and wood to dry dock ships for repairs. But, in this case, plenty of “wholly wood” blocks were also used to address the loading concerns.)
Another major cause for apprehension was whether this ship with higher draft would be able to clear the dry-dock sill without its propeller getting damaged, especially with the available water levels and tidal conditions in Kochi.
Then, there was the water depth issue to tackle. The carrier needed higher water depth to enter the Kochi harbor. The entire outer channel, Ernakulam channel and harbor area, including dock mouth and berths at CSL were dredged to a depth of close to 14 meters.
While CSL was undertaking preparatory activities to enable the ship to dock, INS Vikramaditya had to berth at the ICTT Terminal nearby with a depth of 14.5 meters. This was to facilitate the ship to propel into Kochi on her own power.
According to the government, the work package was contracted and scheduled for 70 days but certain operational requirements demanded significant compression of the time-frame and the ship was undocked and taken out of the yard in 42 days.