Pakistan Navy has recently ordered two systems of anaerobic propulsion MESMA, conceived and carried out by DCN Propulsion, close to Nantes.
This Air Independent System (AIP) will equip the first two submarines diesels with the type Agosta-90B, delivered in 1999 by DCN Cherbourg and 2003 by the arsenal of Karashi.
Built like the second submarine in technology transfer, Hamza, launched this summer in Pakistan, was equipped right from the start with the MESMA. For DCN, the tests at sea of the building, envisaged in the next months, will be crucial, these tests being the first in natural size for the French AIP. If this countryside is conclusive, DCN can hope to take ascending some on its German competitor TKMS and its system containing fuel cells.
The AIP system is very quiet and produces no exhaust heat making the submarine very diffcult to detect compare to the traditional propulsion system submarines, the AIP system will give the submarine a considerably increased autonomy in diving, spending 4 days with nearly three weeks. Making turn a generator which supplies a steam turbine, the system functions according to the same principle as the nuclear propulsion, the hot source being replaced by ethanol. Direct consequence, the ship does not have any more needs to supply its engines in air via the snorkel.
In the future, the fuel of the MESMA will be rather diesel, which will make it possible for the submarines to embark one type of fuel.
The first two Pakistani submarines, Khalid and Saad, will receive a new section of 9 meters containing the AIP, during a major maintenance action. Their length will be carried, as for first Agosta, from 67 to 76 meters and displacement in diving of 1760 to 1980 tons.
"The people involved in the project consider the AIP integration fairly challenging initially when assembly facilities were being set up so it was skipped for the first two submarines. Khalid and Saad both will be equipped with AIP system during their normal overhaul. The AIP was always on the roadmap for all three Agosta 90Bs in the PN service."
In addition to this program, DCN always hopes to sell Pakistan submarines of the type Marlin, or Scorpène. On this contract, the French are in the competition with TKMS.