Torpedo Problems?

[Fishmachine]

Originally Posted by Ula Jolly

OooooOOOOH! SWITCHES POLARITY!
Now THAT'S an eyewidener! And, general enlightener!

Oh, forgive me my english :P
The magnetic field of the ship doesn't switch it's polarity (as it's vertical). But for the torpedo the relative magnetic field polarity suddenly changes when it passes uderneath the ship from (e.g.) N in front to S in back to S in front and N in back. This caused rapid magnetic needle movement which ignited the magnetic detonator.

In the early years of war the magnetic pistons suffered from non-calibrated magnetic needle malfunctions. It was either too dull which caused misfires, or too sensitive which caused early detonation in rough seas or too far from the ship, or fooled completely in northern seas due to earth magnetic pole proximity.

And now, if I'd write that in the first place, would it be much clearer?

EDIT: What did I do to deserve such avatar?