As the first Fletcher built at Bath Iron Works, hull 190, Nicholas, served as the prototype for all Fletcher-class ships built there:
DATA

Name: U.S.S. Nicholas
Type: Destroyer
Namesake: Marine Major Samuel Nicholas
Navy Classification: DD 449
Class: DD 445, Fletcher
Authorized: 17 May 1938
Ordered: 28 June 1940
Builder: Bath Iron Works Corp., Bath, Maine
Builder’s Hull Number: 190
Keel laid: 3 March 1941
Launched: 19 February 1942
First commissioned: 4 June 1942
Decommissioned: 22 April 1946
Reclassified DDE 449: November 1950
Recommissioned: 19 February 1951
Reclassified DD 449: 7 June 1962
Decommissioned: 30 January 1970
Disposition: Scrapped, Zidell Marine, Portland, Oregon.

    Length Overall: 376' 5½"
    Extreme Beam: 39' 8"
    Normal Displacement: 2,050 long tons
    Draft: Light: 8' 1"; Mean: 13' 5" Deep: 22’8”
    Designed Complement: Officers, 34; Enlisted, 295
    Designed Shaft Horsepower: 60,000
    Designed Speed: 36 knots
    Trials Speed:: 37.1 knots
    Screws: Two
    Rudder: One
    Stacks: Two
    Tactical diameter: 950 yards at 30 knots
    Endurance: 4,800 nautical miles at 15 knots.
Initially, Nicholas, like O’Bannon and Chevalier, carried a 1.1-inch anti-aircraft cannon between the “53” and “54” 5-inch gunhouses, but this tended to overheat and jam in service. Later ships mounted a 40mm twin Bofors in this location, with which Nicholas was subsequently retrofitted. In 1944, Nicholas was further modified to carry two more of these twin mounts amidships plus two forward, below the bridge, for a total of ten barrels.

From the beginning, the “Nick” also carried Mk 4 20mm single mounts. Although she left for the war zone without a full armament of these weapons, she picked up more en route and once may have carried as many as 13—including two on top of the pilot house—before settling on seven in 1944: four in the waist and three on the fantail.

Thus Nicholasinitial armament was as follows:

    Primary: 5 x 5-inch/38 cal. in five single mounts
    Long-range anti-aircraft: 4 x 1.1-inch cannon in one quadruple mount
    Short-range anti-aircraft: 6 to 13 x 20mm Oerlikon in single mounts
    Torpedo Tubes: 10 x 21-inch in two quintuple mounts
    ASW: 2 racks for 600-lb. charges; 6 “K”-guns for 300-lb. charges
Her electronics were also typical:
    Radar: SC (air search) and SG (surface search serial No. 3), Mk 37 (fire control)
    Sonar: QC
From January 1944, she was modified to carry the typical 1943–1944 Fletcher-class armament:
    Primary: 5 x 5-inch/38 cal. in five single mounts
    Long-range anti-aircraft: 10 x 40mm Bofors in five twin mounts
    Short-range anti-aircraft: 7 x 20mm Oerlikon in single mounts
    Torpedo Tubes: 10 x 21-inch in two quintuple mounts
    ASW: 2 racks for 600-lb. charges; 6 “K”-guns for 300-lb. charges

References: Friedman, shipmates and Bath Iron Works plans for hull no. 190.