V-2
It was the world's first operational ballistic missile, which caused the Allies quite a few headaches. It was used mainly against London and Antwerp, wreaking havoc in these cities even when the German bomber air force practically no longer existed.
This rocket was launched initially from occupied sites in Western Europe and, toward the end of the war, from Germany itself.
For this reason, V-2 production facilities were constantly bombed. Therefore, their production had to be moved underground. The V-2 rocket was developed by German scientist Wernher von Braun, who later became a leading figure in the Apollo program, which took Americans to the Moon.
Me 262
The Germans were the first country in the world to have a jet-powered fighter aircraft in their arsenal. It was designated the Me 262.
Development of this aircraft began even before the war started, but the conflict accelerated everything. It was a very fast jet fighter, reaching speeds up to 870 km/h (540 mph). It was powered by two Junkers Jumo 004 jet engines.
As a result, the aircraft had no competition in the sky. It was much faster than Allied fighters and bombers. Therefore, pilots in the Me 262 managed to relatively easily destroy even the legendary American Flying Fortresses.
However, the Me 262 was a complicated project with a whole range of problems. Its production was not easy at all, nor was piloting it. Moreover, the Me 262 was deployed only in 1944, when the Germans had very few capable pilots left. But if the aircraft had come into existence two years earlier, the outcome of the war might have been uncertain.
Horten Ho 229
The Horten Ho 229 was in many ways a revolutionary aircraft, but it also couldn't prevent Germany's defeat. The Nazis were unable to deploy it in combat by the end of the war.
The main peculiarity of the Horten Ho 229 was its specific shape. The aircraft had the form of a flying wing, powered by two jet engines. In addition to its high speed and range, this flying wing was characterized by its ability to hide from enemy radars. Essentially, it was the first stealth aircraft.