Detailed: I-52 Japanese Submarine made to specific bulkhead shape. Includes default ready to render scenes.
She is also known as Japan's 'Golden Submarine', because she was carrying a cargo of gold to Germany as payment for matriel and technology. There has been speculation that a peace proposal to the Allies was contained on board the I-52 as well, but this is unlikely on two counts: there is no evidence that the Japanese government was interested in peace proposals or negotiated settlements at that stage in the war; and the Japanese kept an open dialogue with their diplomatic attachs via radio and diplomatic voucher through Russia, and had no need for long and uncertain transfer via a submarine bound for a Nazi-controlled area of western Europe.
It is believed that 800 kg (1,000-lbs) of uranium oxide awaited I-52 for her return voyage at Lorient according to Ultra decrypts. It has been speculated that this was for the Japanese to develop a radiological weapon (a so-called 'dirty bomb') for use against the United States. (The amount of unenriched uranium oxide would not have been enough to create an atomic bomb, though if used in a nuclear reactor it could have created poisonous fission products).
She was also to be fitted with a snorkel device at Lorient. In addition, 35 to 40 tons of secret documents, drawings, and strategic cargo awaited I-52's return trip to Japan: T-5 acoustic torpedoes, a Jumo 213-A motor used on the long-nosed Focke-Wulf Fw-190D fighter, radar equipment, vacuum tubes, ball bearings, bombsights, chemicals, alloy steel, and optical glass.
I-52 ( (52) I G Dai Gojni Sensuikan (I Gojni)?, I-52 submarine (I-52)), code-named Momi (?, 'abies firma') was a Type C-3 cargo submarine of the Imperial Japanese Navy used during World War II for a secret mission to Lorient, France, then occupied by Germany, during which she was sunk.