MTL - Immortal Sword Master - Chapter 989 Long drive straight into 3

An angel made a mistake, resulting in Shiihara Daiki’s death. In order to hide the mistake, he was then sent to a different world. The angel will grant him one wish as a payment for keeping it a secret. Daiki asked for a Heavenly Castle floating in the sky without hesitation.

Suddenly a floating castle appeared in the new world, which causes confusion amongst the people. They attempt to contact Daiki in various ways. A country tries to steal it by force, while another seeks to befriend him. What in the world would Daiki do?

Whenever our ship encounters a tenth-level storm, my comrades-in-arms will not have the slightest worry, because they know that I still have me on board.

- Description from Uukanshu

A scientific genius named Thomas Harrier was transmigrated to an imperial prince body after a car accident that took his life. He found out that he is in a world similar to our own with a timeline akin to early twentieth century. The body that he is occupying was the imperial prince of a failing empire who suddenly rose to power after a successful assassination attempt of his father. Unaware that the attack is just the beginning of what is to come. He faces many challenges throughout. Will Thomas Harrier be able to live his second life in peace while running an empire and getting it back to its former glory? Or will he succumb into a conspiracy lurking within the country's borders?

Expect some:

Cold war era techs.

Super battleship with advanced electronics, propulsion, and fire control systems?
Helicopters?
Missiles?
Modern medicines and equipment?
AC-130?
A nuke?
Challenger or Abrams or Leopard?
F-4 Phantom or MIG-21?
Colored TV's.

Everything!!!

PS. Cover not mine, I just found it on google.

In the beginning, I just wanted to solve life problems.

Then, I didn’t want to admit defeat, I didn’t want to just leave in such a daze.

Next, now that you’ve stood your ground, why not do it better.

Finally, as I have always insisted, when you decide to invest in something, you must do it to the best of your ability!

– One of the greatest actors of the 21st century, Sean Tang

- Description from novelbuddy