The Sea Shadow program was inspired by the F-117 stealth aircraft, which was also the world’s first stealth aircraft. The ship’s propulsion system was a diesel-electric system that can reach a speed of 14.2 knots (26.3 km/h). The Sea Shadow was designed with angled surfaces, an unconventional warship design at the time of its birth. Engineers discovered that the angled surfaces could scatter sonar waves, while also reducing engine noise.