Fangaku!! Tokyo Depths School Life Speedrun

In the era when Nazi Germany began a dangerous motion, a young man aiming for space appeared in this alternate universe "Berlin". His name is Walter, an arrogant man who fears nothing in this world. Together with Paul, a stubborn engineer, he completes the common sense flight battleship Kaiserburg, which is capable of escaping the atmosphere. However, they are chased by the German army because to this. The army has noticed Kaiserburg's overwhelming combat power! (Source: KADOKAWA, translated) *Note: Includes 1 extra chapter.*