Crazy Ivan

Crazy Ivan is a Naval term for a submarine maneuver, characterized by any number of sudden and sharp turns, used by submarine crews to "look behind" their boat using sonar.

Baffles

Because of the acoustic distortions and noise caused by propeller blades, it is nearly impossible for conventional sonar to detect objects directly behind a submarine. So, with sudden turns, the area where the sonar is not effective shifts relative to the current heading of the submarine, causing previous gaps in sonar coverage to be revealed while masking known areas. This gap in sonar coverage caused by the submarine's own propeller is commonly known amongst submariners as the "baffles".

Name and description

The "Crazy" part of the name comes from the fact that these maneuvers were very sudden and could lead a trailing submarine to collide with the submarine performing the maneuver and "Ivan" was a common nickname used to refer to the Russians during the Cold War.

A standard tactic of pursuing submarines would be to closely follow the Soviet submarine hidden right in the sonar gap, causing the U.S. submarine to go undetected. Because of this, there were two dangers for the submarine's crew. The first would be, of course, detection by the Soviet submarine if the sonar gap shifted and the U.S. Navy submarine would be revealed. A common countermeasure was to stop the engine and pumps in the pursuing sub and rapidly go for maximum silence. However, this led to the second danger — collision. With its inertial momentum, the U.S. sub's forward movement would continue with the possibility of collision with the unknowing Soviet submarine dead ahead in the process of turning sharply. An example of a similar manuever, called "Angles and Dangles", gone wrong happened on June 20 1970, when USS "Tautog" collided with a Soviet
Echo class submarine known as "Black Lila". "Angles and Dangles" is a 5 hour dance of random figure eights, sharp turns, and random depth changes. The manuever is executed at the start of a voyage and its purpose is to find out what noise the submarine is making and if anything is stowed in the wrong place. The manuever is similar to a Crazy Ivan although it lacks the latters offensive fury and is a random execution of turns, unlike a Crazy Ivan. Fortunately, both submarines survived the incident..

Most modern nuclear submarines deploy a towed array sonar which specifically covers the baffles, rendering the Crazy Ivan mostly obsolete.

Popular references

The Crazy Ivan phenomenon is used as a plot device to add tension to "The Hunt for Red October", a book by Tom Clancy, and the subsequent movie of the same name. The name is also borrowed for an evasive maneuver executed by the spacecraft "Serenity" in the science fiction television series "Firefly" in the episode "Serenity", though it more closely resembled a Pugachev's Cobra, Kulbit, or even an aerial version of a Bootlegger.

Other uses

* Krazy Ivan is a 1996 shoot 'em up released for both Sony Playstation and Sega Saturn.
* Crazy Ivan is a specific infantry for Soviet faction in , who plants dynamites on any units (except air units) or structures of friend or foe.
* Krazy Ivan is the name of an achievement in the game Team Fortress 2. To get it, the player must kill a total of 100 opponents while underwater and playing as the Heavy, a class whose player character is Russian.
*A Crazy Ivan can also refer to the act of a woman rapidly turning around to catch a person looking at her behind.

See also

* Baffles (submarine).

References

* Sontag, Sherry; Drew, Christopher; Drew, Annette Lawrence (1998). "". Harper. ISBN 0-06-103004-X.
* "Crazy Ivan: A True Story of Submarine Espionage" by W. Craig Reed, William Reed, (ISBN 0-595-26506-5)

External links

* [http://www.pbs.org/wgbh/nova/transcripts/2602subsecrets.html Submarines, Secrets, and Spies] where the former commander of an American submarine is interviewed and the subject is mentioned.
* [http://www.deepspace4.com/pages/military/kursk/kursk.htm A "Kursk" web site mentioning the Crazy Ivan maneuver]
* [http://www.cnn.com/SPECIALS/cold.war/experience/culture/write.along/chapter9.html A description of the maneuver]