Fritz X which was used to bomb and destroy large warships was a German radio controlled bomb. Astonishingly, the Germans did not note that a radio guided smart bomb has it’s greatest weakness in its very name!
The smart part of the bomb was a “sitting duck” pilot who launched the Fritz X and then had to loiter in the air while guiding the bomb with a joy stick on its way to destroy allied warships like the Savannah. The Germans had to regroup after a few of their pilots got shot down trying to guide Max Kramer’s brainchild to its destination of destruction.
The bomb’s manufacturer Ruhrstahl was probably quite disappointed that it could not profit more from its lethal product. Max Kramer moved on to ideas like using the compliant skin of a dolphin to reduce the water drag on ships, submarines, and underwater bombs like torpedoes.