Nevertheless, on September 17 Kapitänleutenant Glattes of U-39 spotted the HMS Ark Royal in his patrol area and was able to close in on her unnoticed. And there occurred the first major disappointment of the U-boat war. Glattes fired a salvo of three torpedoes with magnetic pistols at the carrier, all of which exploded prematurely. Worse yet, the failed attack revealed the boat's position to the escort and the destroyers quickly sank U-39. The crew, fortunately, was saved.
The Admiral was proven once again correct. On October 30th Kapitänleutnant Wilhelm Zahn of U-56 sighted in his area a truly juicy formation: the battleships Rodney, Nelson, the battle cruiser Hood (later blasted by the Bismarck) and a dozen destroyers. With great daring and skill, Zahn eluded the destroyer screen and struck Nelson with a salvo of three. The impact pistol torpedoes clearly slammed against the ship's hull and…simply fell apart. The commander was so depressed by this misfortune for which he was not to blame in the least that Dönitz took him off active duty for a while.
. Consequently, he was proven right when late on April 15 Gunther Prien of U-47 arrived at Bydgenfjord and spotted three large British transports (some 30,000 GRT each) and several smaller ones disembarking troops in fishing boats. Immediately the Raging Bull fired 8 torpedoes with impact pistols at the stationary and overlapping targets, but all of them missed. This could have been a major disaster for the BEF and a valuable help for the outnumbered mountain troops defending Narvik.
The previous day, Kapitänleutnant Herbert Schultze of U-48 (the boat that was to become the most successful vessel of the Kriegsmarine with 312,000 tons sunk over almost 6 years) had attacked the Jutland-veteran battleship Warspite without success near Westfjord.
Again on April 19th Gunther Prien closed in on the Warspite and lobbed in a salvo of two. Those, too, were failures, which robbed the Kriegsmarine of a much-needed respite. The second stage of Operation Hartmuth was hardly going well, with British troops closing in on Narvik and the Royal Navy inflicting heavy losses on German warships as well as on troop and supply freighters.
The next day Prien sighted a convoy south-west of Westfjord, but refrained from attacking because he had lost all faith in his torpedoes. Upon his return he was so infuriated that the told Dönitz: "Herr Admiral, I could hardly be expected to fight with a dummy rifle" (89).
Later into the war, in an analysis of torpedo performance in the period January-June 1942 (Paukenschlag and the apex of U-boat activity in American waters - the richest single harvest of the whole war), it was estimated that only 40% of the ships had been sunk by a single torpedo during that period, while the rest had either required two or more, or had escaped after one or multiple hits. In light of the more than two million tons of shipping actually sunk (a third were tankers), it is easy to imagine what could have been the outcome had the U-boats been armed with the weapon they really needed.
