This Balkon Gerat is the linear ancestor of the linear bow arrays of most western
sonars.The BQR-7 sonar fitted to the Permit/Sturgeon class was a linear array wrapped around the spherical bow array and was used for both tracking and target classification.The sonars fitted to german subs in WW2 had much greater performance than comparable allied sonars.The reason behind this was design philosophy.The Germans needed their sonars for long range target aquisition..having none of the advanced radars which the US and British fitted to their subs for target detection at long ranges.The allied sonars were for short range attack control.The German sonars were low frequency for long range and the allied sonars had high frequency for good spatial discrimination (i,e target speed and direction).

It should be noted most post war sonar development has concentrated on low frequency sonars because they give such long detection ranges (out to 200+
miles under good conditions).German surface ship sonars were based on the same technology and the following example shows how effective German sonars were.The sonar fitted to the Prinz Eugen was a semi circulat array 30ft in diameter which had none of the signal processing associated with modern sonars..its one advantage was its size (the bigger the array the lower frequencies it could hear).This sonar detected a british heavy cruiser at +30,000 yards while the Prinz Eugen herself was steaming at 30 knots.This is outstanding sonar performance
which most modern sonars would be hard put to match.

This sonar was removed after the war and fitted around the sail of a US fleet submarine for tests.These tests and others convinced the USN that quiet operation
(to avoid detection and improve sonar performance)and large low frequency sonars (speherical arrays mounted in the bows for optimal performance) was the way to go.

Rgrds

Ger Wallace.