I was a big fan of zipang (anime) and final countdown (movie), will be like if one Kirov class cruiser modernization return in 1942
Let's start with a few assumptions:
- A McGuffin or plot device transports a fully operational Kirov-class battlecruiser into the year 1942.
- For more or less understandable reasons, the crew decides to assist the Soviet government of the time, i.e. Stalin. While they might not be actual Stalinists, they're patriots, and waiting the war out in Tahiti isn't really an option.
- After a misunderstanding or two, they open communication and Stalin believes that the crew of the Kirov are genuine and willing to help in the Great Patriotic War.
The next question would be just how desperate the Soviet government is at the time:
- The smart move would be to bring the ship to a safe port (in the Far East?) and to put the crew and equipment to work in R&D. One cruiser, no matter how good, is going to wear out. It would be incredibly short-sighted to fire her missiles at the enemy instead of starting to reverse-engineer them.
- Textbooks in her library will be extremely useful, too. In addition to science, they can make use of history books up to the arrival of the ship for reference. They're history, but they have the benefit of hindsight and analysis.
- By contrast, any descriptions of history after the arrival of the ship are going to be questionable. The time travelers will alter events and the butterfly effect makes their knowledge invalid.
- The stupid move would be to send the Cruiser against the German Navy. She is no ASW ship and the German surface fleet was well handled by the Brits.
- If any of the P-700 missiles have a nuclear warhead, using them might be considered if there is a way to employ them against strategic land targets (and if the crew has the required launch codes).
What kind of world do you want to build? A novel, a gaming scenario? That should influence your choices.
- Will any of the characters end up in the Gulag, perhaps in a special Sharashka camp?
- Will any of the characters rise to leadership positions in the Stalinist regime? Do they have to betray anybody?
- How soon until the Soviets can mass-produce nuclear weapons? A bomb they made themselves can be expended more easily. On Berlin? During the Korean War?
- Can they come up with a delivery system to hit the US?
- Even without using nukes, a more confident Stalin might not press the western Allies for a second front. A cold war with the USSR in control of continental Europe, and with a steady stream of reverse-engineered technology to help their R&D?
- The ship will have radar proximity fuses for their guns, plus manuals and at least a few officers who understand the science behind them.
- Quite a lot of computing power. How much depends on when they left the real world and got marooned in the fictional world. Do they have a PC, a programmer, and a compiler? They could compute firing tables for historical artillery and help with other kinds of research.
- The Kirov has turbines for top speed, and three helicopters. Soviet jet and turboprop technology gets a boost.
On second thoughts, the arrival of the time-travelling cruiser might just as well doom the Soviet war effort.
Stalin's paranoia will splash on everybody whose original-timeline-future-self approved Khrushchev's secret speech at the 20th party congress, despite the fact that they were indispensable senior management during the war years.
So depending on who gets the history books first, either a new great purge or a desperate revolt.