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Saturday, July 11, 2009

Brief History of Submarine Construction in Pakistan. (2003-22)

Pakistan Navy Submarine Force was established in April 1964 with the acquisition of first Guppy class conventional submarine from US Navy. Subsequently 03 newly constructed Daphne class conventional submarine were acquired from DCN France in the year 1968-70. Another Daphne class submarines was acquired from DCN France.
Immediately after the acquisition of first submarine, foundation of submarine maintenance infrastructure was laid at PN Dockyard Karachi. Over the years this infrastructure was expanded with state of the art machinery, tools, jigs & fixtures and skill of the work force was also enhanced. The decision for major overhauling of submarines in PN Dockyard proved to be a turning point in the history of submarine force. Till today PN Dockyard has on its credit 30 major overhauls of the submarines.
This rich experience of submarine maintenance coupled with special repairs of pressure hulls of PNSM HANGOR and PNS/M SHUSHUK in 1991-92 and naval construction experience of midget submarines, PNS LARKANA, and auxiliary crafts raised the confidence level of the decision makers to embed the elements of transfer of technology in the acquisition of future submarines. As a result in September, 1994 a contract was signed with DCNI of France to build 03 submarines.
The first submarine was to be completely built in France. Pakistan Navy engineers and workmen were to be trained and qualified in the construction processes. DCN was to assist PN Dockyard to upgrade the infrastructure for construction of submarine. To optimize the available infrastructure some works were shared with KS&EW as well. The first submarine joined PN Fleet in December 1999 as PNS/M KHALID.
The transfer of technology level for next two submarines was to be raised gradually in second and third submarine. This was also necessary to immediately put to use the new acquired construction skills. Based on this principle, three pressure hull sections of submarine No. 2 (PNS/M SAAD) were built in France and delivered in 1998. This enabled the engineers and workmen trained in France to quickly organize and put to use their skills. Even before the delivery of sections of submarine No. 2 the work on major structures was started in December 1997. The three sections were transferred to Section Building Hall using Dual Walking Beams and were pre-outfitted for one year. These sections were lowered in Graving Dock in December 1999 and junctioned together. The outfitting phase in Graving Dock included 14000 equipment and foundations, 6000 pipes, 40 kilometres of cables and 38000 connections. Approximately 30000 quality checks were performed during the construction of submarine No. 2. The second submarine was launched on 24 August 2002 and started its harbour and sea trials. This submarine has completed over 1200 harbour and sea trials and on successful completion this has been commissioned as PNS/M SAAD on 12 December 2003.
The maximum transfer of Technology was envisaged in submarine No. 3. The cylindrical part of the pressure hull was to be built from raw plates. All major structures and appendages were to be built in Pakistan. The work of pressure hull construction also started in 1997, was shared between PN Dockyard and KS&EW. PN Dockyard provided the material after cutting to size and shape on NC cutting machine to KS&EW. This kit of material was rolled/formed and welded to make 12 subsections. These subsections were taken to Section Building Hall in PN Dockyard to make 03 large sections. On completion of pressure hull these three sections were pre-outfitted with decks, bulkheads and large structures. Based on similar construction methodology these sections along with Air Independent Propulsion (AIP) system MESMA, have been lowered into Graving dock on 19 August 2003 and outfiting has started.
The submarine construction at PN Dockyard Department is now fully qualified as per ISO-2000 and its product has been proven and validated. This will meet the need of Pakistan Navy for decades to come. Date of Issue (December 12, 2003)