This design was brought about primarily in an attempt to increase the range and speed of the VIIC model by adding a second stage of boost to the already singly supercharged engines. Range was to have been increased with 35cm widening of the saddle tanks, adding nearly 70 tons to the maximum fuel load. Coupled with these performance issues was the thickening of the pressure hull by another 30cm, giving the Type VIIC/42 a normal diving depth of 300m and failure depth of a staggering 500m. Armour plating for the conning tower, an integral schnorchel and numerous flak weapons rounded out the design which would have taken the basic Type VIIC structure to its absolute limit. The first orders were placed on 16 July 1942 with Germaniawerft although within a year the entire conditions of the Atlantic battle had changed to such a degree that those boats of the 174 total number ordered that had been laid down within the shipyards, were cancelled in favour of Type XXI construction. Ironically it was the Russians who completed the only known examples of the VIIC/42 post-war when they finished the construction of U1174, U1176 and U1177 at the Danziger Werft, Danzig. It is though that they may also have finished several examples from the ordered U2301-U2318 series at Danzig's F Schichau yard as well.