TERMIUM Plus®

From: Translation Bureau

On social media

Consult the Government of Canada’s terminology data bank.

MANOEUVRE IVAN FOU [1 record]

Filter results by subject field Alphabetical list of terms

Filter results by subject field

Alphabetical list of terms

Record 1 2017-10-27

English

Subject field(s)
  • Submarines (Naval Forces)
  • Sonar and Underwater Detection (Military)
CONT

Crazy Ivan is a U.S. Navy term for a Soviet submarine manoeuvre, characterized by any number of sudden and sharp turns, used by submarine crews to "look behind" them. Because of the acoustic distortions and noise caused by propeller blades, it is nearly possible for conventional sonars to detect objects directly behind a submarine. Thus, 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.

OBS

The "crazy" part of the name comes from the fact that these manoeuvre were very sudden and "Ivan" was a common nickname used to refer to the Russians. 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.

Key term(s)
  • crasy Ivan
  • crasy Ivan manoeuvre
  • crazy Ivan maneuver
  • crasy Ivan maneuver

French

Domaine(s)
  • Sous-marins (Forces navales)
  • Sonar et détection sous-marine (Militaire)
DEF

Manœuvre d'un sous-marin qui consiste à effectuer brusquement des virements de bord successifs pour compenser l'incapacité du sonar de détecter les objets situés immédiatement derrière lui, incapacité causée par la distorsion acoustique produite par les hélices.

Spanish

Save record 1

Copyright notice for the TERMIUM Plus® data bank

© Public Services and Procurement Canada, 2026
TERMIUM Plus®, the Government of Canada's terminology and linguistic data bank
A product of the Translation Bureau

Display options

Change the order of display of the official languages of Canada
Option to display the non-official languages (Spanish or Portuguese)
Display definitions, contexts, etc., on records

Features

GCtranslate (available on the Government of Canada network only)

Use this artificial intelligence prototype to translate Government of Canada content up to and including Protected B. Available to employees of selected departments and agencies only.

Writing tools

The Language Portal’s writing tools have a new look! Easy to consult, they give you access to a wealth of information that will help you write better in English and French.

Glossaries and vocabularies

Access Translation Bureau glossaries and vocabularies.

Date Modified: