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This discussion replies to Norman Polmar’s comments in the October 1999 issue of THE SUBMARINE REVIEW regarding my review of Clay Blair’s Hitler’s U-Boat War.

  1. Polmar notes that “Part of the reason for the slow response was that new, more capable torpedoes were being developed. Those weapons took up the effort needed to more rapidly fix older torpedo problems.” This reinforces my comment that solutions were slow to enter the fleet. Germany’s Navy had a problem throughout the war in trying to keep up technologically with the Allies. If their limited torpedo technical establishment chose to work on new designs rather than fix current problems, then those new designs better be worth the choice. They weren’t. By the time the new designs entered service-the T-5, the Lut, the Fat-the U-boats had been decisively defeated.
  2. In response to my observation that U-boats Jacked radar and sonar, he notes that they had radar installed toward the end of the war and their “GHG sonar was the most advanced acoustic detection system in service in any navy. ” These developments came far too late to help the U-boats in their crucial battles in mid-1943 in which they were decisively defeated. True, U-boats had radar installed starting in late 1943, but this radar could only be used when surfaced and because its use tended to betray the U-boat’s position to Allied aircraft, was not much used. GHG is the German acronym for Gruppen-Horch-Great, or Group Listening Device and was a generic term for underwater listening arrays. The GHG thus was not a sonar (SONAR=SONic Detection and Ranging) and I’m willing to concede that passive listening devices installed in arrays (groups) in the U-boats’ bows were good gear, but sonar they were not. When German submarine design focused on the electro boat (Types XXI and XXII)-designed for all-underwater operations-they developed echo ranging gear which took the generic name Sonder Apparatus-U-Boot or SU. This was an extension of work begun in 1938 (S-Great = Sonder-Great fur aktive schallortung) but which suffered delays because of low priority and realization that a submarine using active echo ranging could be detected at a much greater distance than it could detect a target. SU apparatus was installed in some Type Vlls but later removed to make room for radar. New SU apparatus was installed in some Type XXI boats in early 1945 and apparently, the returning signals were processed by the GHG array, and integrated with the torpedo fire control system. Polmar is correct in his statement that the so-called GHG became a model for the U.S. Navy’s AN/BQR-2 and was a key element in an advanced submarine fire control system.
  3. My review stated: “while the Allies continued to improve their weapons, sensors, tactics, and competence, the German posture stayed essentially the same as in 1939, or deteriorated.” Polmar comments that the Germans put to sea advanced torpedoes, including acoustic homing, pattern running, wire-guided, and wake-homing types, and had produced a torpedo that could out-fox Allied Foxer gear. My choice of words was perhaps infelicitous; better if I had said that “While the Allies continued to improve their weapons, sensors, tactics, and competence, despite strong efforts by German weapon developers, the German posture declined relative to that of the Allies.” I believe that German tactics and competence declined absolutely during the course of the war, and that their weapon and system developments to counter Allied developments-ingenious and advanced though they may have been-were too little and too late to affect the outcome of the Battle of the Atlantic. This was the thrust of Clay Blair’s book.
  4. Polmar goes on to comment that although the German war effort was plagued by largely inept leadership, organizational infighting, and production problems, in virtually every field of military endeavor, especially submarines, they were highly innovative. Taken by itself this comment is correct. But one has to ask: “If they were so innovative, why did they lose the war?” Not only did Nazi Germany lose the war, it was resoundingly defeated on all fronts and in all arms. The truth is the Allies were as innovative, if not more so, than the Germans.
  5. Finally he notes that British Admiralty concern about the loss of 84 ships in March 1943 on the North Atlantic convoy runs reflected an ominous trend, in which the rate of sinkings exceeded the rate of new construction. In my review I note the Admiralty’s alarm and their assumption that things were likely to get worse with large numbers of U-boats now available and the coming of better summer weather. Blair tried to deconstruct that alarm. He pointed out that the March sinking rate (635,000 tons) was anomalous and resulted from three or four successful convoys attacks-virtually the first such that had occurred in the North Atlantic. A direct reason for these losses may have been the codebreakers losing German naval four-rotor Enigma for ten days in mid-March, plus the high volume of Allied convoy radio traffic incidents to the Allied Convoy Conference. That it was an anomaly is shown by tonnage losses in February (360,000) and April (328,000). What is not clear is why historians continue to cite this March anomaly as an indication that U-boats came close to winning.

Understandably, until the extent of Ultra codebreaking successes could be revealed, historians could not discuss this aspect. Still, it is a puzzle. In the March 1943 convoy debacles 39 merchant ships and one destroyer out of 200 total ships in four eastbound convoys were sunk, causing Roskill to call this the “crises of crises”. Seldom mentioned is that 12 other convoys sailed these same routes during the same period with only one ship lost.

Blair provides a hindsight assessment of this alarm. He notes that-contrary to Polmar’s assertion-Allied shipbuilding was replacing losses faster than they were occurring and had been doing so since November 1942. In March 1943 American yards alone produced 1,005,000 gross tons of shipping. These figures should have been available in more-or-less real time to Allied ASW assessors, and certainly to historians. Blair also consistently focuses on the “full glass” aspects of the issue: 91.5 percent of North Atlantic ships in convoy reached their destinations in March. These data should have been available to assessors at the time and to historians since.

I alluded to the problems of contemporaneous assessment in my review. The folks in the Admiralty Submarine Tracking Room were trying to assess what was happening from the Arctic to the Indian Ocean. At any one time, a dozen convoys, several ASW Hunter-Killer Groups, and more than 200 U-boats were being tracked, and engaging in one-on-one encounters. Information was time-late and there was a tendency to concentrate on on-going battles. Yet, ASW and submarine warfare is a campaign over a long period where operations research is vital in assessment. OR depends on assessment of overall statistics and depends for its truth on large numbers of trials; if a sufficient number of valid events occur, the OR person can extrapolate the data and make predictions. For these predictions to be valid, boundary conditions should remain unchanged. In March 1943 the boundary conditions were changing rapidly in that the Allies were introducing CVEs and long-range MPA to close the air gap, new weapons and sensors (hedgehogs, Mk 24 FIDO torpedoes, ASW rockets, sonobuoys), and they were on the verge of changing Allied Naval Cypher Number 3, which B-Dienst was reading, to Number 5. The effect of all these favorable developments wasn’t visible in March and for some time thereafter. It is a puzzle why historians don’t see the overall picture today. This is what Clay Blair tried to do.

I am an avid scanner of book catalogs, particularly military books. It pains me as a part-time historian to see the extent to which the Nazi regime and particularly its military machine continues to be the object of fascination as exemplified by the number of books that continue to be published on it. Nowhere is this more evident than in the number of recent books devoted to U-boats. One wonders if a young a-historical generation realizes that the U-boats lost and the Allies won. In any case, the myth that the U-boats came very close to winning seems lodged in the mind of this generation. This is what Clay Blair refuted, but it looks as if his work must go on, after his death.

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