Submarine shipbuilding has several goals. All of them, one way or another, are associated with a decrease in the possibility of detecting a submarine by increasing the distance between it and the water surface, as well as some other factors. Of course, the military-industrial complex is generally a special area, the goals of which are often very different from the aspirations of an ordinary civilian. However, in the proposed article, we will consider some data on the depth of submersion of submarines, as well as the limits in which this value varies.
A bit of history: bathyscaphe
The material will, of course, be about warships. Although man's exploration of the open spaces of the sea includes even a visit to the planetary maximum depth - the bottom of the Marianadepression, which, as you know, is located more than 11 km from the surface of the oceans. However, the historic dive, which took place back in 1960, was carried out in a bathyscaphe. This is an apparatus that does not have buoyancy in the full sense, since it can only sink and then rise due to the tricks of engineering genius. In general, during the operation of the bathyscaphe, there is no question of moving in a horizontal plane over any serious distances. Therefore, the depth of submersion of submarines, which, as you know, can cover huge distances, is much less than the record for a bathyscaphe, at least for now.
The most important characteristic
Speaking of records in the field of ocean exploration, one should not forget about the true purpose of submarines. The military targets and payload that are usually carried on such ships does not only imply the highest mobility required for them. In addition, they must skillfully hide in ideally suitable water layers, emerge at the right time and descend as quickly as possible to the depth necessary for survival after a military operation. In fact, the latter determines the level of combat capability of the ship. Thus, the maximum immersion depth of a submarine is one of its most important characteristics.
Increasing factors
There are several considerations in this regard. Increasing the depth allows you to improve the maneuverability of the submarine in the vertical plane, since the length of the warship is usuallyis at least several tens of meters. Thus, if it is 50 meters under water, and its dimensions are twice as large, moving up or down is fraught with a complete loss of disguise.
In addition, in the water column there is such a thing as "thermal layers", which greatly distort the sonar signal. If you go below them, then the submarine becomes practically "invisible" to the tracking equipment of surface ships. Not to mention that at great depths such a device is much more difficult to destroy with any weapon available on the planet.
The greater the depth of submersible submarines, the stronger the hull must be capable of withstanding incredible pressures. This, again, plays into the hands of the overall defense capability of the ship. Finally, if the depth limit allows you to lay down on the ocean floor, this also increases the invisibility of the submarine to any locating equipment available to modern tracking systems.
Basic terminology
There are two main characteristics that show the ability of a submarine to dive. The first is the so-called working depth. In foreign sources, it also appears as operational. This characteristic shows what is the depth of immersion of submarines, which can be lowered an unlimited number of times over the entire period of operation. For example, the American Thresher normally made 40 dives per year within a given value, until he tragically died during another attempt to exceed it.along with the entire crew in the Atlantic. The second most important characteristic is the calculated or destructive (in foreign sources) depth. Corresponds to its value at which the hydrostatic pressure exceeds the strength of the hull, calculated during the design of the apparatus.
Test depth
There is one more characteristic that should be mentioned in context. This is the immersion depth of the submarine, which is the limit according to the calculations, being below which can cause the destruction of the plating itself, or the frames, or other external equipment. It is also called "test" in foreign sources. In no case should it be exceeded for a particular device.
Returning to the Thresher: with a design value of 300 meters, he went to a test depth of 360 meters. By the way, in the United States, the submarine is sent to this depth immediately after launching from the factory and, in fact, “runs in” on it for a certain time before being transferred to the department ordering it. Let's finish the sad story of Thresher. Tests at 360 meters ended tragically for him, and although this was not caused by the depth itself, but by technical problems with the submarine's nuclear engine, however, accidents, apparently, were not accidental.
The submarine lost its course due to the engine stop, the purging of the ballast tanks did not work, and the submersible went to the bottom. According to experts, the destruction of the submarine's hull occurred at a depth of about 700 meters, so, as we can see, between the testvalue and really destructive there is still a decent difference.
Average numbers
With the passage of time, naturally, the values of the depths grow. If the submarines of World War II were designed for values of 100-150 meters, then subsequent generations raised these limits. With the invention of the possibility of using nuclear fission to create engines, the depth of submersion of nuclear submarines also increased. In the early 60s, it was already about 300-350 meters. Modern submarines have limits of the order of 400-500 meters. While there is clear stagnation on this front, it looks like it's up to future developments, although mention should be made of an extraordinary project created in the Soviet Union in the 80s.
Absolute record
We are talking about the submarine "Komsomolets", unfortunately, tragically sunk, but it still belongs to the unconquered peak in the development of the sea depths by modern submarines. This unique project has no analogues in the world yet. The fact is that for the manufacture of its case, a very durable, expensive and extremely inconvenient material in processing was used - titanium. The maximum depth of submersion of a submarine in the world still belongs to Komsomolets. This record was set in 1985 when a Soviet submarine reached 1027 meters below the sea surface.
By the way, the working value for it was 1000 m, and the calculated value was 1250. As a result, the Komsomolets sankin 1989 due to a strong fire that started at a depth of about 300 meters. And although he, unlike the same Thresher, managed to surface, the story still turned out to be very tragic. The fire damaged the submarine so much that it sank almost immediately. Several people died in the fire, and about half of the crew drowned in icy water while help arrived.
Conclusion
The immersion depth of modern submarines is 400-500 meters, the maximum usually has somewhat greater values. The record of 1027 meters set by Komsomolets is not yet under the force of any of the submarines in service with all countries. A word for the future.
