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Old magnetic sensing Torpedos

  1. Sep 25, 2004 #1
    What size of induced magnetic field strength were the torpedoes homing in on and how were they detecting it?
    Last edited: Sep 25, 2004
  2. jcsd
  3. Sep 27, 2004 #2
    As far as i know, the torpedoes used in WWII were not really homing in on the magnetic field of a vessel.

    The were fired and detonated them selfs once under a vessel.
    This the "knew" because of the disturbance in the magneticfield becouse of a big chunk of steel above them (being the vessel).

    It was so important that the torp's detonated right under the vessel because rather than blowing a hole in the hull, a detonation right under the keel will break the vessel in two because the vessel first is "lifted" out of the water at a point on the keel, putting tremendous stress on the keel, then because of the vacum (spelled right??) that remains after a blast it is stresses the other way.
    A "snapping" motion able of destroying any vessels keel.
  4. Oct 24, 2004 #3
    homing torpedos in late WW2 used sound to locate targets
    some other types ran random paths or circled after a timed delay kicked in

    some of both types some times returned to sub that shot them with bad effects
  5. Oct 25, 2004 #4


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    What the old magnetic sensing torpedos detected was the local disturbance in the earth's magnetic field by all the steel in a surface vessel's hull. Typically the magnetic field lines run nearly parallel to the surface, but as they approch a large ferromagnetic object, the lines of force curve upwards towards it. The torpedos sensed this change in direction and moved toward/detonated beneath a calculated source.

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