Along with Elmer Sperry, he worked on the first gyrostabilizing equipment for US ships, and became known for his contributions to military hardware. In 1913, he left Sperry and formed his own company. In 1920, he started work on the Norden bombsight for the United States Navy. The first bombsight was produced in 1927. It was essentially an analog computer, and bombardiers were trained in great secrecy on how to use it. The device was used to drop bombs accurately from an aircraft, supposedly accurate enough to hit a 100 foot circle from an altitude of 21,000 feet—but under actual combat situations, such an accuracy was never achieved.
The U.S. Government spent 1.5 billion dollars developing this bombsight for military work.