Machinery problems was likely to delay the ships well past their intended delivery dates of 1943 – 44 . Three turbines was delivered by Brown Boveri in 1939 to Arkhangelsk for the Sovetskaya Rossiya , but the Kharkhovskii Turbogenerator Works never completed a single turbine before the German invasion in June 1941 . A prototype boiler was supposed to have been built ashore for evaluation , but it was not completed until early 1941 , which further complicated the production plan .