British Leander-class cruisers
German pocket battleship Admiral Graf Spee
An item dated London, England 19th December referred to naval sources claiming that the fact that the German cruiser of the Köln-class (1) was destroyed by just a single torpedo pointed out that something was wrong with the German methods of building. Another indication was that the relatively small calibre main guns (15,2cm/6”) of the British cruisers HMS Ajax and HMNZS Achilles managed to damage the armour of the German pocket battleship Admiral Graf Spee (1) above expectations. The British blamed the method of electric welding used by the German shipyards to decrease the weight instead of the traditional riveting of armour plates. It was believed that electric welding could reduce the weight of a ship of 10.000 ton with around 900 ton.
1. The Köln belonged to the Königsberg-class light cruisers consisting of the Karlsruhe, Königsberg and Köln of which the first two were sunk in 1940. 85% of their hulls were welded instead of riveted. On 13 December 1939 were the Leipzig and Nürnberg of the Leipzig-class, the successors of the Königsberg-class, torpedoed by the British submarine HMS Salmon although surviving, both ships more as 90% welded.
2. The British HMS Ajax and the New Zealand HMNZS Achilles were of the Leander-class light cruisers3. Of the Deutschland-class armoured ships well known as pocket battleships later classified as heavy cruisers. Laid down by Reichsmarinewerft Wilhelmshaven, Germany on 1 October 1932, launched on 30 June 1934, commissioned on 6 January 1936, after the Battle of the River Plata with British/New Zealand cruisers on 13 December, scuttled by her own crew in the harbour of Montevideo, Uruguay on 17 December 1939.