USS N-3, possibly during her voyage up the St. Lawrence River in 1921.
History
United States
Name	USS N-3
Builder	Seattle Construction and Drydock Company, Seattle, Washington
Laid down	31 July 1915
Launched	21 February 1917
Commissioned	26 September 1917
Decommissioned	30 April 1926
Stricken	18 December 1930
Fate	Scrapped, early 1931
General characteristics
Type	N-class submarine
Displacement	348 long tons (354 t) surfaced 414 long tons (421 t) submerged
Length	147 ft 3 in (44.88 m)
Beam	15 ft 9 in (4.80 m)
Draft	12 ft 6 in (3.81 m)
Propulsion	Diesel-electric
Speed	13 knots (24 km/h; 15 mph) surfaced 11 knots (20 km/h; 13 mph) submerged
Complement	25 officers and men
Armament	4 × 18-inch (450 mm) torpedo tubes

USS N-3 (SS-55) was a N-class coastal defense submarine in commission in the United States Navy from 1917 to 1926. She saw service during World War I.

N-3′s keel was laid down on 31 July 1915 by the Seattle Construction and Drydock Company at Seattle, Washington. She was launched on 21 February 1917, sponsored by Miss Bertha Coontz, daughter of the commandant of Puget Sound Navy Yard, Captain Robert Coontz, and commissioned on 26 September 1917 with Lieutenant William R. Munroe in command. N-3 was the last submarine constructed in Seattle.

Following sea trials in Puget Sound, N-3 and her sister ships USS N-1 and USS N-2 departed Puget Sound Navy Yard on 21 November 1917. The three submarines arrived at Naval Submarine Base New London at Groton, Connecticut, on 7 February 1918. From there, with World War I in progress, N-3 patrolled along the New England coast and off Long Island.

In July 1918, N-3 was the target of a friendly fire incident. She was on patrol in the Atlantic Ocean during the predawn hours of 23 July, lying on the surface while charging her batteries in calm, hazy weather with bright moonlight, when at 02:55 she suddenly sighted at a range of only 1,800 yards (1,650 m) one of the ships of a convoy of five troop transports which had departed New York City on 21 July carrying U.S troops to Europe. The British armed transport Minnekahda, carrying 3,800 U.S. troops, soon also appeared, headed straight at N-3 and only about 200 yards (183 m) away. N-3 immediately made a preliminary recognition signal by firing a green flare, then sent a recognition signal by blinker light. Minnekahda did not respond except to blow her steam whistle. N-3′s crew heard someone aboard Minnekahda order "Fire!" As N-3 continued to flash the recognition signal by blinker light, N-3′s commanding officer hailed Minnekahda, calling out "Don't fire, this is an American submarine!" At that instant, one of Minnekahda′s guns fired a 6-or-7.5-inch (152 or 191 mm) round (according to different sources), and the shell hit N-3 forward at the waterline, failing to explode but inflicting considerable damage and causing leaks. Minnekahda closed to a range of 50 yards (46 m), close enough for N-3′s crew to see men aboard Minnekahda and hear them receive an order to load. As N-3 continued to flash the recognition signal, several men on N3′s deck yelled "Don't fire!" and "Don't shoot, this is the N-3!" Finally, someone on Minnekahda asked where N-3′s flag was. N-3′s crew immediately brought a United States flag on deck and shined a light on it. Minnekahda promptly ceased fire. The U.S. Navy destroyer USS Preble, serving as one of the convoy′s escorts, approached at flank speed as if to ram N-3, and N-3 made recognition signals and backed at full speed, avoiding a collision with Preble by only a few feet. N-3 hailed Preble, which stopped and sent a boat to N-3 to assess her damage. N-3 had suffered no crew casualties, but Minnekahda′s unexploded shell was found in N-3′s forward superstructure, and N-3′s torpedo compartment was partially flooded. After pumping 2,800 US gallons (2,331 imp gal; 10,599 L) of diesel fuel overboard to lighten herself forward, N-3 proceeded to New York Navy Yard in Brooklyn, New York, on the surface under her own power.^[1]

Following permanent repairs at the New York Navy Yard, N-3 returned to the Submarine School at New London for patrol and training duty through 1920. When the U.S. Navy adopted its hull classification system on 17 July 1920, she received the hull number SS-55.

Departing New London on 1 June 1921, N-3 proceeded to Toledo, Ohio. One of the first submarines to navigate the St. Lawrence River and the Great Lakes, she put in at three ports in Canada — Halifax, Nova Scotia; Montreal, Quebec; and Port Dalhousie, Ontario — before arriving at Toledo on 25 June 1921. She remained there for 11 days, open to the public for inspection. Departing on 6 July 1921, she returned to Naval Submarine Base New London, arriving on 20 July 1921.

On August 16, 1923, N-3 was damaged in a collision with the Green Fleet Company's tanker Monree off of New London. The Navy Department reported that the submarine's periscope was "carried away" and the submarine's conning tower was considerably damaged. No crew members were injured in the incident and the submarine was able to return to port on her own.^[2]

From New London, N-3 subsequently cruised along the east coast of North America from Halifax to Philadelphia, Pennsylvania, conducting training cruises. Departing New London, she headed for the Philadelphia Navy Yard on League Island in Philadelphia, where she decommissioned on 30 April 1926. She was struck from the Naval Vessel Register on 18 December 1930 and was scrapped in mid-1931.

•  This article incorporates text from the public domain Dictionary of American Naval Fighting Ships. The entry can be found here.

• Photo gallery of USS N-3 at NavSource Naval History