The NR-1 Deep Submergence Craft is a US Navy nuclear-powered ocean engineering and research submarine. Casually known as "Nerwin," it was launched at Groton, Connecticut on January 25, 1969, completed her initial sea trials August 19, 1969, and is homeported at Naval Submarine Base New London. It maneuvers by four ducted thrusters, two in the front and two in the rear. The vehicle also has planes mounted on the sail, and a conventional rudder.
NR-1's missions have included search, object recovery, geological survey, oceanographic research, and installation and maintenance of underwater equipment. NR-1's unique capability to remain at one site and completely map or search an area with a high degree of accuracy has been a valuable asset on several occasions.
Following the loss of the Space Shuttle Challenger in 1986, NR-1 was used to search for, identify, and recover critical parts of the Challenger craft. Because it can remain on the sea floor without resurfacing frequently, NR-1 was a major tool for searching deep waters. NR-1 remained submerged and on station even when heavy weather and rough seas hit the area and forced all other search and recovery ships into port.
The NR-1 performs underwater search and recovery, oceanographic research missions and installation and maintenance of underwater equipment, to a depth of almost half a mile. Its features include extendable bottoming wheels (yes, Nerwin is a sub with wheels), three viewing ports (yes, Nerwin is a sub with windows), exterior lighting and television and still cameras for color photographic studies, an object recovery claw, a manipulator that can be fitted with various gripping and cutting tools and a work basket that can be used in conjunction with the manipulator to deposit or recover items in the sea. NR-1's sail lacks a bridge; surface vision is provided through the use of a television periscope permanently installed on a mast in her sail area.
NR-1 has sophisticated electronics and computers that aid in navigation, communications, and object location and identification. It can maneuver or hold a steady position on or close to the seabed or underwater ridges, detect and identify objects at a considerable distance, and lift objects off the ocean floor.
NR-1 can travel submerged at approximately four knots for long periods, limited only by its supplies. It can study and map the ocean bottom, including temperature, currents, and other information for military, commercial and scientific uses. Its nuclear propulsion provides independence from surface support ships and essentially unlimited endurance. NR-1 is generally towed to and from remote mission locations by an accompanying surface tender, which is also capable of conducting research in conjunction with the submarine.
- Primary Function: Deep submergence research and engineering vehicle
- Hull Number: NR-1
- Class: no class; this is a one-of-a-kind ship
- Builder: General Dynamics (Electric Boat Division)
- Displacement: 400 tons
- Length overall: 44.4 m (145 ft 9-7/16 in.)
- Pressure hull length: 29.3 m (96 ft 1 in.)
- Diameter: 3.8 m (12 ft 6 in.)
- Maximum beam (at stern stabilizers): 4.8 m (15 ft 10 in)
- Maximum navigational draft: 4.6 m (15 ft 1 in.)
- BOX keel depth (below base-line): 1.2 m (4 ft O in.)
- Power Plant and Propulsion
- One nuclear reactor
- one turbo-alternator
- Two motors (external)
- two propellers
- Four ducted thrusters (two horizontal, two vertical)
- Design operating depth: 725 m (2375 ft)
- Speed, surfaced/submerged: 4.5/3.5 knots
- Mean Draft: 4.6 m (15 ft 3/4 in.)
- Endurance: 210 man-days (nominal) 330 man-days (maximum)
- Crew: 2 officer, 3 enlisted, 2 scientists
- Armament: None