Half Moon, 1948 (WHEC-378)

Jan. 26, 2021

Half Moon, 1948

Photo of Half Moon


Radio call sign: NBQR

Half Moon was named for a bay on the coast of California south of San Francisco.

Builder: Lake Washington Shipyards, Houghton, WA  

Commissioned: 15 Jun 1943 (USN)
                            30 Jul 1948 (loaned to USCG); commissioned as Half Moon on 14 September 1948; transferred permanently to USCG on 26 September 1966

Decommissioned: 15 Jul 1969; sold 29 April 1970


Length:  310' 9 1/2" oa; 300' 0" bp  

Draft:  12' 4" full load aft

Beam:  41’ max  

Displacement:  2,498 fl  

Main Engines:  Fairbanks-Morse, direct reversing diesels   (2.677:1); Model 38RD8-1/8 O.P.

SHP:  6,400  

Performance, Maximum Sustained: 17.4 kts, 9,970 nautical mile range

Performance, Economic: 11.1 kts, 20,523 nautical mile range

Complement:  10 officers, 3 warrants, 138 men 

Electronics: Radar: SPS-23; SPS-29B; AN/SPA-66; AN/SPA-52
                    Sonar: SQS-1

Armament:   1 x 5”/38 Mk 30 Mod 12; 2 x 81mm Mk1; 2 x .50 Caliber MG's; 1 x Mk 10 Mod 1 A/S projector; 2 x Mk 32 Mod 5 torpedo tubes; 1 x Mk 57 Mod 4 director; 1 x Mk 34 Mod 11 fire-control radar

Class History:

The Casco class ships were built as small seaplane tenders by the US Navy. They were designed to operate out of small harbors and atolls and had a shallow draft. The fact that the class was very seaworthy, had good habitability, and long range made them well suited to ocean-station duty.  In fact, an assessment made by the Coast Guard on the suitability of these vessels for Coast Guard service noted:

"The workmanship on the vessel is generally quite superior to that observed on other vessels constructed during the war.  The vessel has ample space for stores, living accommodations, ships, offices and recreational facilities.  The main engine system is excellent. . . .The performance of the vessel in moderate to heavy seas is definitely superior to that of any other cutter.  This vessel can be operated at higher speed without storm damage than other Coast Guard vessels."  [Memo, CDR W. C. Hogan, Commanding Officer, CGC MC CULLOCH to Commandant “SUBJ; CGC MC CULLOCH, Sutiability [sic] for use as CG Cutter.”, 12 February 1947; copy in 311-Class Cutter File, USCG Historian’s Office.] 

Once they were accepted into Coast Guard service, a number of changes were made in these ships to prepare them for ocean-station duty. A balloon shelter was added aft; there were spaces devoted to oceanographic equipment and a hydrographic winch and an oceanographic winch were added. 

See DANFS for naval service.

Cutter History:

From 30 July 1948 to 15 July 1969, Half Moon was stationed at Staten Island and Governors Island, New York. She was used for law enforcement, ocean station, and search and rescue duties in the Atlantic. 

On 24 and 25 August 1951 she assisted M/V Castello Guadalest at 39°30’N, 58°32’W.  On 14 August 1963 she assisted the civil authorities in Bermuda to fight a fire aboard the M/V Coastal Service at Ordnance Wharf, St. Georges, Bermuda.  The Half Moon was in Bermuda while on a reserve training cruise.  On 11 January 1967, Half Moon seized four U.S. fishing vessels seven miles northwest of Dog Rocks following a shooting incident in which one person was killed and another wounded. 

Half Moon sailed from New York Harbor on 1 April 1967, bound for duty in the waters of the South China Sea with Coast Guard Squadron Three.  She was under the command of CDR Emmett G. McCarthy.  The cutter served in theatre from 4 May to 29 December 1967.  She was one of the four original cutters to make up this Coast Guard combat squadron.  She and her sister cutters were assigned to Operation Market Time, a naval interdiction of enemy supply lines at sea, as well as naval gunfire missions to support allied forces on land.  She conducted nine of the latter missions.  On 12 September 1967 she was ordered to fire on an enemy build-up in An Xugen Province.  Her gunfire killed at least one enemy soldier and destroyed three Viet Cong fortifications.  By the time of her return home on 22 January 1968, she had killed at least 13 Viet Cong soldiers, destroyed 64 military emplacements and structures, and sank four sampans.  She also served as a home base for 50-foot Navy Swift boats and participated in search and rescue cases.

On 11 July 1968 she helped medevac an injured crewman from the German M/V Brunsdeich.

After decommissioning, the Half Moon was sold for scrap to Cantieri Navali, Santa Maria, Italy for bid price of $66,000.


Photo of Half Moon


USCGC Half Moon, no date/photo number; photographer unknown.


Photo of Half Moon


"COAST GUARD IN VIETNAM: Five white 311-foot cutters of the recently established Coast Guard Squadron Three assigned to "Market Time" coastal surveillance in South Vietnam are tied up alongside Navy repair ship USS JASON (AR-8) after arriving at Subic Bay, P.I.  From the left are the USCGC HALF MOON, USCGC YAKUTAT, USCGC GRESHAM, USCGC BARATARIA, and USCGC BERING STRAIT."  Coast Guard Photo Rel. No. 6201; 4 August 1967; photo by CDR Richard Morse, USCG, commanding officer of Barataria.

Photo of Half Moon


"CUTTER HALF MOON RECEIVING STORES: While on Market Time patrol in South Vietnam, the 311-foot U.S. Coast Guard Cutter HALF MOON is replenished with stores by high line transfer from the Navy cargo ship USS CASTOR.  The cutter receives four replenishments a week while underway from various Navy vessels of the 7th Fleet.  In exchange here the HALF MOON passed a Coast Guard birthday cake (celebrating the Coast Guard's 177th anniversary, August 4, 1967) by high line to the CASTOR."  Coast Guard Photo Rel No. 6212 (HALF MOON-090567 (01)) [EAS?]; photographer unknown.

Photo of Half Moon

"Crewmen cart high explosive projectiles across the deck of the 311-foot U.S. Coast Guard Cutter HALF MOON for the ship's five-inch gun to hurl at a Viet Cong emplacement near a U.S. Special Forces Camp in the Song on Doc area, South Vietnam.  The HALF MOON provides gunfire support when needed by U.S. Shore forces in addition to her Market Time patrol duties of preventing contraband materials from being supplied the Viet Cong from the sea." Coast Guard Photo Rel. No. 6215; 12/67; photographer unknown.


Photo of Half Moon

"Battle Station -- The five-inch gun on board the 311-ft. U.S. Coast Guard Cutter HALF MOON blasts at a Viet Cong stronghold in the Song Ong Doc area in South Vietnam." Coast Guard Photo Rel. No. 6218; EAS/bjh; photographer unknown.


Halfmoon, Cutter Subject File, USCG Historian's Office

Dictionary of American Naval Fighting Ships, Vol. III (1968), pp. 208-209.

"Listings: AVP's"; compiled and written by LCDR J. P. Smith, USCGR, copy in 311’ Class Cutter File, USCG Historian’s Office.

Memo, CDR W. C. Hogan, Commanding Officer, CGC MC CULLOCH to Commandant “SUBJ; CGC MC CULLOCH, Sutiability [sic] for use as CG Cutter.”, 12 February 1947; copy in 311-Class Cutter File, USCG Historian’s Office. 

Robert Scheina, U.S. Coast Guard Cutters & Craft, 1946-1990 (Annapolis: Naval Institute Press, 1990), pp. 10-16.

Ship's Characteristics Card: USCGC Halfmoon, 14 March 1967.