The current situation of the Kuznetsov, captured in February this year, is covered with thick snow. Although it looks very beautiful with a "silver coating", it is suitable for the maintenance of the ship. Murmansk, on the other hand, will not reach temperatures of over 10 degrees Celsius until May, so it is difficult to carry out outdoor repairs. Otherwise, if the temperature drops below minus 20 degrees Celsius, how can we work?

The maintenance and modernization upgrade of the Kuznetsov aircraft carrier has been going on for a long time. It returned to Russia for major repairs after completing its combat mission off the coast of Syria in 2016. At that time, its boilers and steam turbines had major malfunctions, and the journey from Russia to Syria was filled with thick smoke... Due to the impact on its speed and the image of the Russian Navy, it was necessary to carry out major repairs to the power system and upgrade some equipment.

The reason why the Kuznetsov has been under maintenance for so long is due to various factors, such as technical and financial issues, which have slowed down the project progress. The most important issue is the lack of a large dry dock.

The dry dock that is being intensively constructed is said to be basically completed in November, and the "storage ships" will enter the dry dock at the end of the year for comprehensive bottom maintenance work in 2022... Some observers may ask if Russia does not have a large dry dock?

During the Soviet Navy era, major repairs of large ships had to go to the "Nikolayevsk Shipyard" in Ukraine, which was also the birthplace of the "Warehouse Ship" and "Varyag". However, the Northern Fleet base in Murmansk was located in the Arctic Circle due to its perennial low temperatures. Although the water temperature did not reach zero at the coldest time, the problem was that the soil layer would freeze, making construction at the excavation site very difficult. Therefore, it was not suitable to excavate and build large dry docks for shipyard maintenance. Instead, large floating docks were used for ship maintenance work. The sunken DP-50 dock was imported from Sweden in the 1980s.

The problem is that after the collapse of the Soviet Union, the relationship between Russia and Ukraine became extremely tense. Russian warships could no longer go to Ukraine and had to deal with the use of floating docks. As a result, the DP-50 was also in disrepair for a long time... The "storage ship" did not undergo a bottom inspection, and the bottom was not repaired. Who dares to let it re-enter service?

The dry dock of the "Little Star Ship Maintenance Center" also has two small dry docks connected in between, which will become a dry dock capable of repairing ships of over 80000 tons in the future.

In order to address the issue of the inability to repair large warships, Russia can only renovate shipyards so that they can repair large surface vessels such as aircraft carriers and cruisers in the future, and ballistic missile submarines may also be repaired here.

Some observers may ask, isn't a dry dock just digging a big pit on the coast and pouring cement? What's so difficult about it? Repairing dry docks of less than 100000 tons, such as "storage ships," is relatively easy to construct in warm areas, but when constructing in frozen soil layers, the issue of cement pouring must be considered.

Generally speaking, large-span buildings such as shipyards first dig pits, then use building materials such as coarse steel bars, cement bricks, various specifications of gravel, waterproof asphalt, etc. to build dock walls, and use high-grade concrete slurry to pour them into one. However, the solidification time of the cement slurry is different, often due to the different solidification times of the previous and subsequent pours (cement curing), which results in the cement not being able to form a whole. Therefore, when constructing in high-temperature areas, ice blocks should be added to the previous cement slurry to reduce its water evaporation rate and solidify together with the later poured cement slurry at the same temperature to form a whole.

However, the construction of frozen soil layers requires stricter temperature control for cement slurry. If the cement slurry poured before and after cannot form a whole, it will reduce the scouring ability of the sea during dock opening, and will also form subtle cracks. When the harsh winter arrives, the building materials will "shrink", causing the cracks to gradually expand, resulting in material peeling, local collapse, and other phenomena. Severe shipyards will be scrapped within a few years. Due to construction difficulties, the Northern Fleet did not have large dry docks since the Soviet era.

At present, the progress of the dry dock is still normal, and it is estimated that it will be completed by the end of this year. The Kuznetsov aircraft carrier also has a reliable maintenance site. If a thorough bottom inspection can be completed this year, it is estimated that it will be put back into service before 2022, and its combat effectiveness will slightly increase by then.

In April of this year, Russian Defense Minister Shoigu inspected the "Little Star Ship Maintenance Center". In fact, the Russian Navy's carrier based aviation can hardly afford to wait. Without the aircraft carriers Su-33 and MiG-29K, it is impossible to conduct actual ship training, which will lead to increasingly unfamiliar technology. The cost of starting from scratch is too high!

Overall, Russia's construction of a dry dock has indeed alleviated the difficulty of repairing large Russian warships. If the construction is in good condition, coupled with careful maintenance, it can be used for decades without any problems, and also solves the embarrassing situation of large ships in the Northern Fleet that cannot be repaired/maintained without a large floating dock.

Source: Guoke Huanyu