Which submarine introduced the teardrop-shaped hull to the U.S. Navy?

USS Albacore introduced the teardrop-shaped hull to the U.S. Navy. Launched in 1953, she was an experimental diesel-electric submarine designed to test a hull form optimized for underwater speed and maneuverability.

Earlier submarines often retained shapes influenced by surface ships, because they needed to operate efficiently both submerged and on the surface. Albacore’s designers instead focused on submerged performance. Her rounded, streamlined body reduced drag, and her control surfaces and propeller arrangement were also developed with underwater movement in mind.

The experiments proved highly influential. Later American submarines, including USS Skipjack and many subsequent classes, used related hydrodynamic principles. The resulting silhouette became one of the defining visual features of modern submarines.

Albacore was not a nuclear-powered attack submarine; she was a research and development vessel powered by diesel-electric machinery. That distinction is important because the submarine’s major contribution was its hull design, not a new reactor system.