Narwhal-class (SSN-671)

Summary

Description

The USS Narwhal (SSN-671) was a submarine operated by the United States Navy. Her construction began on January 17, 1966, at the Electric Boat Division of General Dynamics Corporation in Groton, Connecticut, and she was launched in 1967. Commissioning followed in July 1969, establishing her as a unique vessel within her own class under project SCB 245.

Featuring groundbreaking design elements for its time, the Narwhal implemented several quieting technologies to become the era's quietest submarine. She employed a natural circulation S5G reactor and a direct-drive turbine propulsion plant that operated without reduction gears at a low shaft speed. Some noise reduction efforts proved problematic but set the stage for later technological advancements. Innovations like less powerful, two-speed coolant pumps, seawater injection for condensers, and ship service turbine generators at lower RPMs contributed to its stealth. Her "turtleback" structure hinted at the use of remote-controlled underwater vehicles or experimental towed sonar arrays. Although the Narwhal's design offered numerous advantages, certain components such as the propulsion turbine and turbine generators faced issues and were not replicated in subsequent models.

During her operational history, the Narwhal was noted for a busy deployment schedule, punctuated by three major overhauls and consistent performance in Arctic environments. Her distinguished service included multiple commendations for excellence in operations and battle efficiency. The Narwhal’s notable incident occurred during Hurricane Hugo in 1989 when she sustained damage in Charleston, South Carolina, and survived the storm by submerging in a river.

Technical specifications

Photo of Narwhal class