The Rising World Company

Vonn the Engineer has invented the airplane in a magical world, using his secret knowledge from Earth. He's just crashed next to a living, unholy dungeon with a prisoner to save. And when he returns, there's real work to do.
So far Vonn has used the arcane rules of the "System" to earn spells and other powers. There's no dark overlord to slay, so he and his friends are free to build. This kingdom's technology is just starting to take off, partly thanks to airships and tools powered by the physics of magic crystals. It's time to fly farther, get richer, and make discoveries. And get noticed by the powerful... which is not always a great idea. The biggest change Vonn and company set in motion might not be a machine at all.
This is book 2 of an optimistic series in the "isekai" genre: modern person in another world. It's also "LitRPG" or "GameLit": game-like rules within the fantasy world. Features slice-of-life adventure, some fighting, the invention of the telephone game, and zero harems