France will provide India with the "Independent Aerodynamic System" (AIP) for submarines, which is used to upgrade India's latest submarine, the "Karwari" class. According to the Russian Satellite News Agency on January 31, India and France signed an agreement on cooperation in the field of "independent of aerodynamic system". The report points out that "independent of aerodynamic system" enables conventional submarines to stay underwater for several weeks, and the underwater endurance is greatly improved. Therefore, conventional submarines equipped with this system are called "quasi nuclear submarines". It is reported that the "independent aerodynamic system" manufactured will be used to upgrade the "Karwari" class submarine. The "Karwari" class is a new type of conventional submarine built by India by introducing the relevant technology and data of the "Tuna" class submarine from France. The first ship, the "Karwari", was put into service in December 2017. The second "Kandeli" was put into service in September 2019; The third "Karanje" was commissioned in the Indian Navy in March 2021, the fourth "Vera" was delivered to the Indian Navy in November 2021, and the fifth "Vajir" was listed in December last year. After the delivery of the sixth "Karwari" class submarine in 2023, the construction of the project will be completed. The "Kalwali" class submarine has a total length of about 67.5 meters, an underwater displacement of about 1600 tons, and a maximum underwater speed of up to 20 knots. The submarine has excellent stealth performance, advanced noise reduction technology, low radiation noise level, and hydrodynamic optimization of shape. The weapon is equipped with six 533mm torpedo launchers, which can launch heavy wire-guided torpedoes and submarine missiles. The total carrying capacity of torpedoes/missiles is 18. Without torpedoes and missiles, the submarine can carry 30 mines to carry out minelaying tasks. According to previous reports of Indian media, France is helping India advance the fifth generation fighter plane and conventional submarine plan. The new agreement signed by France and India will promote the deepening of the constantly developing strategic relationship between the two countries. Although the introduction of "independent aerodynamic system" will help improve the operational capability of Indian submarines, Indian submarine forces are now facing difficulties. (Outlook New Era)