The Artificial Dragon

The Artificial Dragon, or AD for short, is an elongated rigid airship that uses hydrogen and ten internal combustion engines to keep afloat for up to 80 hours of flight time. It's roughly 800 feet long and carries 4'900'000 cubic feet of hydrogen. The problem with hydrogen is that it's highly flammable and the fact that it was used as airborne warfare but also not uncommonly erupted in a fireball itself, killing the soldiers inside, gave it the name - based on the myth that dragons breathe fire.
Artificial Dragons gave humans a new advantage in warfare against the technologically less advanced non-humans who relied on magic which only very rarely has long-distance spells available, much less ones that can be repeated during a battle. Artificial Dragons cannot carry a large load, but they are high enough that they pose a threat that very few settlements can defend against. Plus the risk that these airships can explode without much warning is also used as a tactic, deliberately steering the burning wreckage that is about to explode into enemy lines and settlements.

"If we're going down, we're going down with a bang!"

Lothar X. to his oldest son.

The Artificial Dragon was invented by Arnoald Hindlburg as hired by Lothar X. to provide the Empire with a new and powerful weapon that can be used to transport troops, provide air support, and bring devastation down on the enemy — costs be damned to the Empire. 
It took a lot of trial and error, but ultimately, Arnoald and his two daughters managed to build the enormous monstrosity that brought fear and terror to the realms and proved to the non-humans that human warfare was not just a force to be reckoned with in close encounters, but also proved to be damning from directions that no one had any hopes to prepare for.