Subsim: 16 Years on the Web and a Trivia Contest!

[PacificWolf]

He's making "Crazy Ivan" Which means the sub is making full 360 degrees turn to check if anyone follows her.

[geetrue]

Originally Posted by PacificWolf

He's making "Crazy Ivan" Which means the sub is making full 360 degrees turn to check if anyone follows her.

Not 360 degrees ... they usually just check the baffles and go back to the course they were on the reverse side.

A Crazy Ivan is a Soviet submarine maneuver, characterized by any number of sudden and sharp turns, used by submarine crews to "look behind" them. Due to the acoustic distortions and noise caused by propeller blades, it is near-impossible to use conventional sonar behind a submarine. With the sudden turns, the area where the sonar wouldn't function would shift relative to the current heading of the submarine, causing previous gaps in sonar coverage to be revealed while masking known areas. A Crazy Ivan is a method to clear a submarine's baffles.

In real life on the open sea's crazy ivan's weren't the problem ... the chicken dances were even worse.

Whenever a Russian submarine detected another submarine (usually our side) they would steer straight for it.

Just one problem with this manuever ... in the 1960's we had not yet figured out how to tell what depth a contact was at with any certain certainety.

Thus the name, "Chicken dance" first one to change course was a chicken. Lot like jet fighter pilots headed for each other, except they had radar.