"Eunometic" wrote in message
om...


The German Type XXI u-boat had the an array sonar that was unusually
accurate and capable of ranging (and thereby plotting and evading
attacking ships) german hydrophones were based on passive arrays
electronicaly processed and distributed around the hull and were far
more accurate and sensitive than allied ones. Sonar ranging both
active and passive allowed the Type XXI to attack without use of
periscope.


In theory, in practise the vast majority of type XXI boats
built were of such poor quality that they were unfit for
service and only one ever went on patrol. The list of ships
sunk by this type follows

Start of List
End of List

Keith