The birth of digital acoustics
Look in history - This is a look into the future.
V. Dudko. Submarine Commander K-492
V. Dudko. Submarine Commander K-492
More than forty years have passed. During the Cold War, at the end of the 70's and the beginning of the 80's, each time our submarines met with the American, Soviet submarines lost this fight, significantly inferior to the American in the range of sonar detection. At the same time, for the most part, industry was imposed on us that we had achieved parity with US and NATO boats. Apart from the general opinion, there was another, the opposite, which they tried to hide away. In practice, the SSBN and other multipurpose boats of the first and second generation could simultaneously be in the salvo position with a foreign plaque only under very successful circumstances. With the outbreak of war, our boats could be destroyed without even entering into an underwater duel. Our submariners were not yet well aware of the acoustic capabilities of the first, second generation submarines and modifications of the transitional third generation. And even more so, we did not study and did not know the Americans. The maximum that the industry was offering us to search for boats even on the 671 RTM project was a noise detection path and ear acoustics. While foreigners already had both digital signal processing and the low-frequency range. This information was made top-secret for their own boats. As a result, we did not deal with noise. The Americans spoke loudly about the acoustic portraits of boats, but we only found out about it. Moreover, even for trying to find out more officers they frightened a special department. But the war would have led to the death of most of our boats if nothing had changed. That is why the secret K-492 raid on Bangor in 1982 shocked the Americans.
The public did not know about it, I think it does not know now. Proof of this is, among all others, personal independent developments and observations of the commander of the boat, which in practice have become a set of measures implemented by the naval specialists of the K-492 submarine, who, in their opinion, did not obey the directives of the authorities and the accepted scientific and technical doctrine the development of hydroacoustic means for detecting and compensating for structural defects of the ship, continued to work according to the approved plan for the development of means for processing hydroacoustic their signals and the introduction of new tactics. Even in unequipped conditions, with the opposition of certain officials, Soviet K-492 submarine officers in the 1980-1983 years managed to independently develop the necessary methodology for using imported digital equipment, and using it, increase the stealth of the boat and introduce new tactics for searching, tracking and fighting, as a result, achieving not only parity with American boats, but also tactical superiority.
To identify their own sonar field and its discrete components (this was crucial for the stealth of the boat), the results obtained by applying a spectral analysis of the noise of the boat were taken into account, as a result, the crew managed to achieve several convincing victories when meeting with American boats. This was confirmed by the results obtained at sea and presented in the documents, as well as in the reports of the American Pacific Fleet command for the 1982 year, which are still not available in the open press. Therefore, today the idea comes to mind that the absence of signal processing systems, especially in the low frequency range, on Soviet submarines could be intent (high treason). It is impossible to believe that a power having such potential, weapons and missile weapon, could not cope with the development of equipment for digital signal processing, especially since imported devices were successfully used on a Soviet ship.
In the Doctrine of Submarine Anti-Submarine Warfare, adopted in 1981, sonar in the United States was called an element of strategic nuclear deterrence. The advantage of American boats in hydroacoustic detection means over Soviet boats with ballistic missiles would result in the fact that with the outbreak of military confrontation all missile boats of the USSR would be destroyed at the same time. And it took only 4 minutes. The very first results obtained when working in a tactical group with the SSBN convinced us of the above. The adversary called hydroacoustics an element of nuclear deterrence and an element of nuclear advantage over the Soviets. But we stubbornly did not notice that we and Soviet hydroacoustics were being pushed into a dead end. Executives fleet at the prompting of the industry, they were engaged in hydroacoustics, but it was necessary to deal with the processing of signals from marine targets, and first of all with digital processing of the hydroacoustic signal, i.e., hydroacoustics as a branch of physics had nothing to do with it.
Our first experience with Skat was a negative result. At the first conclusions to the sea after the construction of the boat, the acoustics heard everything that was buzzing in the sea, and that nobody was buzzing. Target detection distances were several times larger than before. But it was impossible to determine (classify) the target, evaluate the distance, and other parameters of the target for using weapons. There was a problem. There were no obvious criminal acts in the signal processing itself, the crime was deliberately smeared into many insignificant events in space and time, but if we collect a lot of seemingly insignificant events that we, identifying, eliminated, starting from the elimination of coherent pairs of mechanisms, methods signal processing, GEM operation modes, enemy tactical elements, the influence of its sonar field on the stealth of the boat, the range of mutual detection, the choice of areas of military service and a number of others, it becomes clear that of these nuances that are integrated into a whole, it was formed by the advantage of the American boats, which they enjoyed. It was necessary, having endowed our boats with antidote, to level the destructive consequences of the existing subversive policy. There are no criminals, but there is crime to undermine national security. And, apparently, not only in sonar. And everywhere in the areas of science and technology strategically important for the country's security. Measures were needed to counter this.
It took the creation of a special program for testing the KBR (ship’s combat calculations) and special training for the commanders and hydroacoustics of the division’s boats, a separate area for studying the conditions for the detection of foreign boats using spectral analysis equipment. It was necessary to convey to the leadership of the fleet and the country the importance of a new development direction in acoustics - a digital mobile signal processing system in order to accustom everyone to the data obtained using new techniques. However, in the end, they were forbidden to talk about it at all, referring to the same notorious secrecy and provisions of long-outdated tactical manuals. Moreover, the detection of foreign boats sometimes met with distrust, the question was asked: why didn’t the commanders of other boats detect, and if they did, then they did not?
The first significant obstacle to confirming contact was the technical capabilities of the recording equipment. The standard "Mayak-205" tape recorder could not compare with the four-track "B&K" tape recorder. And second: not every time it was possible to transfer the contact aviation PLO, which confirmed the presence of a boat on buoys or other means of detection. Often the reports of other commanders did not confirm the distance of mutual detection of boats, when in the exercises the boats of the “blue” and “red” converged to the distance of detection and could not find each other. And this was obvious, because no one taught them this.
Confirmation of the benefits of digital signal processing could only be practice. The first planned and completed joint combat service of the 671 RTM project in the tactical group with the SSBN confirmed the worst assumptions. Previously, such services were not planned, and they did not go further than a one-time verification of the absence of tracking. It was believed that multi-purpose boats compromise the SSBN and reduce the secrecy of the group, and the accuracy of the reckoning of the 1-2 generation was worse than that of the SSBN. Therefore, the output of K-492 as part of the TG changed the prevailing opinion, and work in tandem with the SSBN made it possible to identify unmasking signs when the SSBN moved under one side. It was believed that it was economical and secretive, but in reality it was the other way around. Since the discovery of the cruiser, it has been revealed:
- pronounced work of one line of the shaft and a clear manifestation of the shaft-lobed components, including when the laminar flow is disturbed, created by shifting the vertical rudder to maintain course and redistribute the loads on one side, including GTZA and turbogenerators;
- separation of the elements of the target’s movement — course, speed, beginning and end of circulation, distance and a number of other features that form an integral picture of tracking and maintaining contact from different directional angles at considerable distances;
- sonar field configuration (HAP), i.e. Acoustic portrait of a boat.
V. Dudko, the commander of the submarine K-492. Photo from the author’s archive
All this fit into the framework of the previously obtained results of tracking American boats in Avacha Bay. The first contact with the IPL on orders from the command post was transferred and confirmed by the aviation of the fleet when the IPL was removed from the tail of the SSBN. Upon arrival at the base, the officers of the acoustic range were called on the boat, who analyzed the noise on the B&K instrument set. After that, the specialists of the test site, the fleet and science conducted a detailed analysis and analysis of the detection, tracking and processing of the spectrum on the B&K equipment by the crew, and then left a copy of the record, and sealed the rest and sent everything to Moscow to the special. Institute archive. And so it was every time after discovery.
Now it was already obvious that the recordings on the standard Navy tape recorder of the worst quality “Mayak-205”, which supplied all the boats except gurgling and croaking, yielded nothing. But we were required to confirm everything only by regular means. Of course, there was gibberish, and other equipment was needed.
Swimming in the TG made it possible to identify new classification features and take a fresh look at the place of digital signal processing in the practice of commanders.
The approach to the SSBN after initial detection lasted more than 6 hours. The primary classification was carried out through the prefix, and the results did not raise doubts about the correctness of its work. At the distance of the 100-120 cable, the mark acquired distinct forms, and the acoustics heard the target. Now the pla has taken up a position in the sector on KU and began escort. The movement continued for another five hours, maneuvering made it possible to remove the GAP RPKSN. When the sonar field (HAP) of the SSBN was removed, the boat returned to the position of joint movement along the route. The countdown from the point of visual detection of the SSBN on the HAC screen and the objective classification, where the acoustics heard the noise of the target, to the point of detection of the target using a spectrum analyzer made it possible to determine the distance of detection of the SSBN. It turned out to be equal to 32 miles, i.e. The first SSBN detection distance was over 300 cable.
This was the first meaningful and confirmed in all ways digital contact, which made it possible to practically evaluate the possibilities of digital signal processing. So far this was only the first case of detection, which made it possible to verify the reliability of the classification and form the basis for subsequent systemic work. This “experiment” gave great hopes and laid the foundation for further systematization of data and development of the methodology. Of course, this phenomenon itself required a certain popularization among the commanders of other boats and ships and should have been alerted by the command, which for the first time received similar SSBN detection distances in a protected area when classifying a boat with a confidence of 100% at a distance of more than 30 miles. It was difficult to believe in this because before none of our submarines had found any other submarines on the SSBNs beyond the 30-50 cable.
But it was true and a breakthrough, the first wide step forward and slap in the face to all opponents of spectral analysis. The experience of sailing in a tactical group made it possible to get rid of the mistakes of boat commanders when searching for and tracking a foreign boat and to apply the new tracking tactics adopted by the K-492 crew after several discoveries by Americans in the Avacha Gulf. Having got rid of outdated dogmas, in the future the 671 RTM pr. Boats were monitored using the spectrum on both 27 nodes and 33 nodes. As a result of the development of new techniques, one after another the characteristic unmasking signs of the field of the submarine cruiser began to be revealed:
- the main discrete noise components of the SSBN (HAP) and the maxima of these components in directions relative to the axis of the ship;
- a pronounced shaft-blade diagram during the operation of one shaft line and a clear manifestation of the shaft-blade components due to a violation of the laminar flow on the boat's propeller, as well as a change in the load created by the vertical rudder shifting to maintain course during operation of the power plant with one side; identification of a discrete component that occurs during the operation of one side, called by the Americans "fishing hook";
- separation of the elements of the target’s movement — course, speed, the beginning and end of circulation and circulation control, which made it possible to determine the angle of rotation of the target at any distance in the presence of contact, distance and a number of other features that form an integral picture of tracking and maintaining contact from different course angles and distances ;
- detection in one of the zones of the distant GAP of the SSBN of the tracking American plat. After which it was forced out of the Sea of Okhotsk, and the crew of the multi-purpose boat proposed new methods for checking the absence of tracking;
- the developed new methods for checking the absence of tracking of the SSBN, radically increased the probability of detecting boats watching the SSBN, worked out the method of spectral analysis of target noise, determining the target speed accurate to the 0,5 node, the beginning and end of circulation, and the rotation angle accurate to one or two degrees at a distance in 200-300 cable. Monitoring the tracking distance and the continuous determination of the elements of the target’s movement made it possible to maintain a reliable position for the use of anti-submarine missile weapons at extreme distances, which was previously almost impossible.
Here it was also necessary to revise the acoustic and technical characteristics of the 667 project submarine and its modifications, about which its creators and submariners spoke. Due to the fact that the designers of our nuclear submarines convinced the Navy command, and those the USSR government, that the level of underwater noise of Russian RPK SNs are indistinguishable from the noise level of the US nuclear submarines, an established opinion emerged that allowed us to accept the SSBN’s high stealth and combat stability as an axiom . A certain part of people who are not inclined to analysis and sanity, or most likely pursuing opportunistic goals, or deliberately introducing deliberately destructive decisions into the government, uniting Russian military specialists, scientists and politicians, began to propose the idea of deploying 70-80% on nuclear missile submarines nuclear potential of Russia. They argued that in the event of a sudden nuclear attack on Russia, the secrecy of navigation and the military stability of our missile nuclear submarines would preserve Russia's nuclear potential for a retaliatory strike. Now this statement was in great doubt. What is it: incompetence or malice aimed at destroying Russia's nuclear potential?
Indeed, when planning the first and subsequent operations of the fleet, the probability of destroying the SSBNs in various patrol areas, in the face of the threatened period and the outbreak of war, was always calculated. And these calculations, as a rule, provided sufficient grounds for taking adequate measures to maintain the nuclear parity of the warring parties. But! Unlike stationary launch sites and even mobile complexes, where the initial data are practically unchanged and verified to the third digit, the combat stability of the SSBN included at least two indicators that were not true: the probability of detecting and tracking the SSBN by American boats and stationary systems, and this figure was more than 50%. And the second indicator is the degree of protection of the patrol area of the PKK SN, which was significantly lower than the declared indicators taken in the calculations. Those. even according to one indicator, the SSBN's secrecy, it was already impossible to achieve the required combat stability. But! This was not even allowed to be said out loud. Now it was necessary to solve this dilemma.
To refute the arguments of our cabinet “strategists” was not within the power of the naval loners. Apologists of the SSBN’s theory of high stealth, referring to the opinion of foreign experts and the “parity” in the noise of the USSR and US nuclear submarines, declared that the combat stability of missile nuclear submarines in the ocean is much higher than the survivability of ground mines of strategic weapons, strategic aviation and mobile mobile systems with strategic missiles . Therefore, more than 70% of the country's nuclear potential is located on American nuclear missile submarines. Great Britain and France do the same. But the NATO countries provided the combat stability of missile nuclear submarines with the technical characteristics of nuclear submarines and an extensive global surveillance system in space, in the air, on the water and under water. The USSR did not have such opportunities. Nevertheless, some scientists have expressed the idea that the detection and long-term tracking of the enemy by the Soviet missile nuclear submarines in the ocean requires huge financial and material resources. In their opinion, not a single country in the world can bear such expenses, which means that it cannot constantly control the areas where our missile nuclear submarines are located. Academician B. Makeev in his article "Marine strategic nuclear forces and the maintenance of strategic stability" wrote:
“Calculations show that the achievement of an acceptable probability of their (missile nuclear submarines. - Aut.) Detection requires huge expenditures of search forces. But even with the detection of the Strategic Rocket Forces (strategic missile submarines. - Auth.), The likelihood of maintaining prolonged contact with it by sonar and other search means is extremely small. Studies conducted by supporters of the high secrecy of the RPK SN at the Center for the Study of Disarmament, Energy and Ecology at the Moscow Institute of Physics and Technology, taking into account the hydrology and noise of the latest generations of RPLSN, confirmed the conclusion that, along with a low probability of detecting submarines (submarines. - Auth.) cannot keep track of detected missile carriers for a long time. ”
This conclusion, to put it mildly, was incorrect. And this "inaccuracy" was confirmed by examples from the experience of the US Navy, referring to the inaccessibility of our data. But this data was not available only to us, and the Americans widely used it.
The US and its allies have created global underwater surveillance systems. These systems for first and second generation boats and even transitional projects were very effective, not to mention the effectiveness of tracking American boats.
Swimming in the TG with the SSBN and the experience of K-500, which the American easily followed the entire BS, and then provoked an attack on a Russian boat, confirmed the concerns that arose. Indeed, the strategist, with all the conditions of stay at sea being equal, looked in front of the 671 RTM multipurpose boat of the project helpless and defenseless. It is obvious that the commanders of nuclear missile submarines, due to the technical capabilities of the SSBNs, could not objectively evaluate the results of their stealth during the campaigns.
In turn, in order to reduce noise and remove the ship’s DS, as well as relying on the design features of the 671 RTM ave., The crew was able to switch certain mechanisms to form a “smooth” acoustic field, removing the main unmasking discretes, which really deprived the enemy of many advantages when meeting in the sea. There are reviews about this in the report of the commander of the aircraft carrier Enterprise following the results of the Flitex 83 exercise at the stage of tracking the 671 RTM project for AMG, when the boat carried out reconnaissance in battle.
Evaluating the activities of the USSR Navy's 671 RTM project in the course of the exercise, they concluded that this plan is quiet and represents a challenge to the SOSUS system. The predicted detection range of this project’s TASS antenna should be at least 20 miles, and in fact 3-5 miles. The TAK TASS antennas were ineffective even if acoustic reconnaissance specialists from the Naval Intelligence Support Center were on board the ships. The same result on the system "LEMPS".
To counteract the initial detection of SSBNs upon leaving the base, a coastal deployed maneuvering underwater surveillance system was proposed and tested, which no longer allowed the U.S. Navy to detect and secretly observe our strategists and boats for a long time. But, unfortunately, the obvious paucity of these search groups did not provide adequate protection for routes and patrol areas, so they continued to monitor missile submarines, starting from the base, in the seas adjacent to our coast and in territorial waters and further into the ocean zone.
It is necessary today in Russia to talk about the combat potential of the Navy's submarine fleet, I focus on the fleet’s multi-structure in the interests of the SSBN as the main deterrent, and take adequate measures. And today, authoritative and knowledgeable naval submarine officers are required that can defend this position in the country's leadership. This issue should be discussed by the Security Council, the State Duma, the Federation Council, this should be discussed in the Government of the Russian Federation, in the General Staff of the Armed Forces of the Russian Federation, and this should be reported to the President of the Russian Federation. It is necessary to exclude any possibility in which our modern combat surface ships and submarines at sea may not be operational due to poor acoustics, other signal processing and weapon control systems. You must always worry about this. It is obvious that naval veterans should also be involved in this, including the Admiral Club, the Maritime College of public organizations and other respected organizations that have experience and knowledge that can contribute constructively to the development of the Navy.
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