The base minesweeper of the new generation “Ivan Antonov”, the first serial ship of the project 12700 “Alexandrite”, September 19, 2018 was withdrawn along the Neva to Lake Ladoga to undergo factory road tests. As bmpd writes, after passing all the inspections, the minesweeper built by the Sredne-Nevsky Shipyard in St. Petersburg may be transferred to the fleet at the end of this year. In total, three serial ships of the project 12700 should be built under the contract with the Ministry of Defense of Russia.
Construction of “Ivan Antonov” was conducted since January 2017. This minesweeper was to become the second serial ship of the project 12700 after “George Kurbatov”, laid in April 2015. However, this ship was seriously damaged in the fire in the factory in June 2016, after which the corps of the unfinished “George Kurbatov” was sent for restoration. As a result, “Ivan Antonov” was the first of the serial lot launched (April 2018) and became the first serial ship of the project 12700. The main ship of the project is “Alexander Obukhov” , put into operation in December 2016.
The third serial trawler should be “Vladimir Emelyanov”, laid in April 2017. The displacement of the basic mine-sweeper of the project 12700 is 890 tons with a length of 61.7 meters, a width of 10.8 meters and a draft of 2.7 meters. The ship is capable of speeds of up to 15 knots, and its range is 1,5 thousand miles. Autonomy of the minesweeper’s sailing is ten days. The ship is armed with one anti-aircraft artillery gun AK-306 caliber 30 millimeters with ammunition for 1500 rounds and an anti-aircraft launcher for eight Igla missiles.
Ships of the type “Alexander Obukhov” are equipped with universal contact trawls OUKT-B, pair contact tractor PKT-B and universal wide-band acoustic trawls SHAT-U. These devices are used to neutralize the various types of mines installed by the enemy, including magnetic, acoustic and galvanic impact. The 12700 project also provides for the formation of a special anti-mine contour of the ship, which includes high-performance hydroacoustic stations and several underwater robots with sonar.
The main feature of the trawlers of the project 12700 is their world’s largest hull made of their monolithic fiberglass by the method of vacuum infusion. The essence of the technology lies in the fact that in a special vacuum chamber, a glass fiber preform is preformed on a special tooling, which is then poured with a liquid binder based on plastic. After that, the entire blank is evacuated and solidified. The result is a rigid molded structure.
The advantage of the fiberglass body is its complete non-magnetic properties. This means that magnetic mines that trigger in the presence of a large amount of metal near the minesweeper will not explode. In addition, the use of fiberglass for the manufacture of the ship’s hull makes it possible to make its overall design lighter, which significantly reduces the draft. Due to this, the minesweeper is able to operate in coastal zones and in shallow waters.
In addition to the first contract for the delivery of three 12700-series trawlers – Ivan Antonov, Georgy Kurbatov and Alexander Obukhov – the Sredne-Nevsky Shipyard is building three more such mine crafts. The first minesweeper from the second batch, Yakov Balyayev, was laid in December 2017, and the second one – Peter Ilyichev – in July 2018. In total, up to the end of 2027, ten minesweepers of the Alexandrite project are planned to be included in the Russian Navy.