Newcomb’s armament was that of a typical Fletcher-class destroyer from 1943–4: five 5-inch guns in single mounts, ten 40mm guns in twin mounts and ten 21-inch torpedo tubes in quintuple mounts plus 20mm guns and depth charges.
DATA

Name: United States Ship Newcomb.
Type: Destroyer.
Namesake: First Lieutenant Frank Hamilton Newcomb, Revenue-Cutter Service.
Navy Classification: DD 586.
Class: DD 445, Fletcher.
Builder: Boston Navy Yard, Charlestown, Massachusetts.
Keel laid: 19 March 1943.
Launched: 4 July 1943.
Commissioned: 10 November 1943.
Disposition: Decommissioned: 20 November 1945; Stricken: 28 March 1946; Sold for scrap: Mare Island Navy Yard, October 1947

    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
Her electronics were also typical:
    Radar: SC (air search) and SG (surface search), Mk 37 (fire control)
    Sonar: QC
Newcomb still carried this armament when hit off Okinawa on 6 April 1945. She was scrapped rather than repaired following her return to the West Coast.