Torpedo crisis
In 1940 the so-called torpedo crisis occurred in the German Navy , when many submarine attacks on ships failed, especially during the invasion operations in Norway ( Weser Exercise Company ), because the G7 torpedoes failed.
The faults in the torpedoes that were only discovered after lengthy investigations and subsequently eliminated were mainly due to inadequate testing, contradicting economic interests and the competition between the Torpedoerprobungskommando (TEK) and the Torpedoversuchsanstalt (TVA).
history
background
The most important torpedo of the German Navy was the G7 , which had been in series production since 1934 . This was available as a steam-gas-powered and electrically powered version, which was either equipped with an impact igniter or a newly developed magneto . The variant with magneto ignition was more effective, as it exploded under the hull of an opposing ship and the resulting gas bubble broke the keel of the ship, which was mostly irretrievably lost.
Shortly after the outbreak of World War II , reports from German submarine commanders about failures in torpedo shots increased. The torpedoes either simply ran under the enemy ships or exploded well before or after the target or not at all. Two early incidents are particularly noteworthy: Twelve days after the outbreak of war, U 39 fired two torpedoes from a distance of only 800 m at the British aircraft carrier Ark Royal , but they detonated prematurely; and at the end of October, U 56 was able to approach a naval formation with the then largest battleships of the Royal Navy ( Hood , Nelson and Rodney ) and shoot a fan of three at the Nelson , with the torpedoes hitting the hull but not exploding.
The height of the crisis was reached in the spring of 1940 when a large number of downed torpedoes failed during the invasion of Norway . In retrospect, it was estimated that if the torpedoes had worked, at least hits on one battleship, seven cruisers, seven destroyers and several transport ships would have been achieved. Despite the massing of enemy ships and good shooting positions, no effective torpedo hits could be achieved in Norwegian waters with one exception.
Reactions
For the crews of the submarines, the torpedo crisis was a depressing experience which, in addition to the technical skills, significantly weakened the morale. Attacks on superior warships had failed several times despite excellent firing positions and prudent procedures. This initially confirmed the proponents of a German surface strategy with capital ships. Admiral Dönitz , however, referred to the potential possibilities that the submarine weapon would offer with functioning torpedo technology.
In the course of the Norwegian campaign, von Dönitz therefore gave the instruction to only use torpedoes with impact fuses. The torpedoes were provided with a switching mechanism so that it was now possible to switch manually from magneto ignition to impact ignition . However, there were also more failures with impact fuses when shots from submarines.
causes
Two components were mainly responsible for the failure of the torpedoes: the depth control and the combat pistol with the ignition device. With torpedoes that regularly ran too deep and thus under the targets, it turned out that the maximum deviation from the preset depth was not half a meter as intended, but up to three meters. This was caused by excessive air pressure inside the torpedoes. As a result, the valve, which determined the depth from the difference between the internal pressure of the torpedo and the surrounding water pressure, controlled the torpedo deeper than intended. The high pressure in the position control chambers of the torpedoes arose because they were not airtight and the pressure inside the torpedo rose when the submarine expelled compressed air into the interior of the boat during its diving trips. The fact that the submarines were often and long pushed under water by the British defense forces exacerbated this problem.
The errors in the depth control, however, could not explain the misfires. This was due to the ignition mechanism, the sensitive relay of which moved due to the drive vibrations and triggered the ignition contact. An aggravating cause was that the natural fluctuations and irregularities of the earth's magnetic field in the northern latitudes also had an impact on the magneto.
The impact detonators could cause the initial charge to deflagrate if the firing pin failed too quickly and could fail due to jamming at angles of impact below 50 °.
A literature source, on the other hand, assumes that the demagnetization of the enemy ships deployed off Norway and the failure to take into account the particularly strong and rapidly changing currents in the Norwegian fjords played an essential role in the shooting training of the submarine commanders.
Legal proceedings
In 1941, von Dönitz turned to the Reich Court Martial in order to bring the responsible technical officers and civil servants to account. Due to meticulous preparation and numerous technical questions, almost seven months passed between the indictment in May and the conviction in December 1941. The court found that the torpedoes had not been subjected to the necessary tests, but there was poor communication between the TVA and TEK departments also to the industry prevailed and there were too many requests for changes to an already imported weapon. The head of the TVA and the inspector of the torpedo inspection (superior department of the TEK) as well as two technical officers of the TVA were sentenced to prison terms, but were released after six months and were then back to work in the armaments sector. Another fundamental weak point in the process was that it was wrong to leave the development, production preparation and testing to an official facility, whereupon the Navy forced a division between government agencies and industry.
solutions
As early as autumn 1939, a working group was founded under the chairmanship of the former chief designer of the torpedo Ernst-August Cornelius , which was able to solve the problems relatively quickly. A multitude of small changes have improved the depth control and the problem of the sensitive relay of the combat pistol has been fixed with an improved suspension. From the summer of 1940 the G7 torpedo was considered usable for warfare and was fully used again from 1941.
In the further course of the war, the German side developed torpedoes that ran independently of pressure according to the program or listening direction, such as the Wren , FAT or LUT .
The US Navy had similar problems during World War II, known as the torpedo scandal.
literature
- Cajus Bekker : Damned Sea - A war diary of the German Navy . Frankfurt a. M., Berlin, Vienna: Ullstein, 1975, ISBN 3-548-03057-2 , pp. 111-130.
- Paul Herbert Freyer: Death on all seas - a factual report on the history of the fascist submarine war. Berlin: Military Publishing House of the German Democratic Republic, 1983, pp. 67–71.
- Eberhard Rössler : The torpedoes of the German submarines. Mittler Verlag, ISBN 3-8132-0842-7 , pp. 83-88.
Web links
- The boats without a gun
- The Norwegian operation and the Torpedo Crisis (English)
- Armaments and armament testing in German naval history with special consideration of the Torpedoversuchsanstalt (TVA)
Individual evidence
- ↑ a b c d military history. Historical Education Journal. (The torpedo crisis in World War II.) (PDF; 3.79 MB).
- ^ Bagnasco, Erminio: U-Boats in World War II. Motorbuch Verlag, p. 57, ISBN 3-613-01252-9 .
- ↑ Eberhard Rössler: The torpedoes of the German submarines . Mittler Verlag, Hamburg, Berlin, Bonn 2005, ISBN 3-8132-0842-7 (Chapter 7.3 The torpedo failures and efforts to eliminate them, page 83ff).
- ↑ Heinz Trompelt: Another view . Factual report from a torpedo Obermech. Maat and Fähnrich zS driven on U-459 and U-172. Books on Demand GmbH, Norderstedt 2006, ISBN 3-8334-4481-9 (Chapter V The "Torpedo Crisis" during the Norwegian Campaign, pages 137-162).