Baffles (submarine)

Krazy Ivan is the name of a submarine maneuver, which was marked by U-boat drivers of the U.S. Navy to refer to a tactical maneuver Russian or Soviet submarines. In this maneuver is usually attempted immediately after a turn of the deaf sector in the wake of - behind the boat - listen to discover as possible pursuers.

Expiration

In this maneuver, led by the Soviet submarines on patrol often, drove the Soviet captains at certain time intervals a lateral avoidance maneuvers. It often with combinations of geometric figures such as Eighth and wavy lines and driven without depth change. Only rarely is a " Krazy Ivan " only a full circle (as it is often represented in relevant media). These maneuvers will often attempts to navigate the area directly behind the boat, to keep the risk of collision, the boat tracked at a distance.

Cause of the maneuver

The purpose of the maneuver was the tactics American hunting submarines to follow enemy submarines extremely close in their wake. Due to the location of the sonar dome in the bow of the ship and because of the propeller noises in the stern of the ship will be built behind the submarine a deaf area that is not intercepted in passive sonar. Ultimately, should be as followers are discovered by passive sonar.

Effectiveness and dangers

Since the boat was pursued mostly a submarine with ballistic missiles and thus almost always larger than the tracked hunting U- boat, it had a correspondingly larger turning circle, so that the pursuers could simply ride a full circle under certain circumstances. A major problem of these maneuvers is the danger of collision with the tracker, especially when trying to navigate his "own wake ." According to reports it to have come through such maneuvers himself up in the 1990s, still underwater collisions. Such collisions are far more dangerous for the persecuted boat than for the pursuer, as the rear area of ​​a U- boat with the passages of the drive shafts and steering gears naturally far more sensitive than the front section, which usually contains rather not existential facilities such as the Sonardom, the loss of which certainly is painful, but not or hardly affected the buoyancy of the submarine. But even relatively small transverse or shear loads on the drive shafts, shock loaded in the longitudinal direction can leave their storage lose its tightness, which can result difficult to control leakage cross sections by also at shallow depths.

Countermeasures

A possible countermeasure is the immediate stop of the machine and "Down Rules" of the nuclear reactor of the tracker boat, which then, however, a link ( " braking distance " ) in an uncontrolled manner drives, which may come dangerously close to the boat pursued. Alternatively you can try, if possible, " join " the maneuver.

Need

Submarines that use a tow sonar, could really do without this maneuver as the drag sonar covers the dove field, but also American or with other nations lead associated boats ( especially strategic missile submarines ), to make sure such maneuvers by which are mentioned in the non-Russian submarines then usually " Angles and Dangles " (but is also the so-called commuting by boat in the USN so called ). Especially before reaching the periscope such a maneuver of all submarines is used, then "clearing baffles" means. So this is typical defensive maneuvers, reportedly, also part of the Perisher - Course of the Royal Navy. On NATO submarines dice are almost always used, allegedly even the official basic equipment includes among American submarines to ensure the randomness of timing and configuration of this particular maneuver. For submarines, the non-towed sonar use ( ed), is / was one of the few if not the only way to track down potential pursuers.

Notable cases

Tracking

The former commander of the USS Lapon (SSN -661 ), Commander Chester Whitey Mack, who managed to track a Russian missile submarine of the Yankee class a large part of its patrol in the manner described, is quoted as follows:

" He changed the course every 90 minutes. There were neither 89 minutes nor 91 minutes, so it was exactly 90 minutes ( exactly these predictable regularity to the American cube prevent loss of generality ). That was the longest time I could not sleep the whole time. He went up, we went up; he went down, we went down. And sometimes we went pretty deep. We made this funny old dance, you know, two six- thousand -ton ships that revolve around them. "

Collision

One of these collisions occurred on June 20, 1970: Near Kamchatka in the North Pacific Ocean likely caused the American submarine USS Tautog (SSN -639 ), the Sturgeon class such a " collision " with the Soviet submarine K -108 echo II class after a 180 ° maneuver. The Tautog was operating before the Soviet submarine base at Petropavlovsk -Kamchatsky and probably tried to track the outgoing K -108. The tautog seem to be caught in the tail of K -108. The American submarine was looking after the collision as quickly as the width where it allegedly took up hull noises, which were interpreted as a possible sinking of the Russian boat. When the Tautog then arrived at Pearl Harbor, they found all the pieces of one of the screws of the Soviet U- boat in the remains of her tower. 1992 was known by Russian naval officers that the K -108 had survived the incident and was able to reach their home port without loss, what you up to then was apparently in circles of the U.S. Navy not clear.

Media

The madman Ivan is also used in the submarine literature in order to create tension, as used, for example, Tom Clancy, the maneuver several times in Hunt for Red October, which seems rather a bit strange in the presentation of the film of the same name, because the Red October on the tailfin occurring in the Russian submarines of the third generation streamlined container for the powerful towing sonar of hydroacoustic complex " SKAT " bears.