Achernar (AKA-53) was laid down under a Maritime Commission contract (MC hull 208) on 6 September 1943 at Kearney,
N.J., by the Federal Shipbuilding and Drydock Co.; launched on 3 December 1943; sponsored by Mrs. Adela Rogers St. John; acquired by the Navy on 29 January 1944; and commissioned on 31 January 1944, Comdr. H. R. Stevens in command.
[[Image:USS Achernar.jpg|right|350px|USS Achernar]]
The last week in May found Achernar in Plymouth, England. On 1 June, she was designated the 1st Army's headquarters ship. On 6 June, she steamed across the English Channel and, at 1609, anchored in her preassigned position in Baie de la Seine, France. For the next few days, she acted as a nerve center for troops fighting for a foothold in France. On 11 June, the 1st Army's headquarters disembarked; and, at 1148, Achernar got underway for England. After a three-day respite in Plymouth, the ship moved to Roseneath, Scotland, to take on the cargo and personnel of two construction battalions. On 19 June, she returned to Plymouth to onload materials to repair damaged assault craft and, on 22 June, got underway for the assault area in France. While on station, she Underwent several enemy air attacks. The cargo ship again left the French coast on 29 June to return to England and arrived in Plymouth on 1 July. On 5 July, the ship was ordered to sail as a part of Task Group (TG) 120.6, which was bound for the Mediterranean to support the invasion of southern France. The ship entered the harbor at Oran, Algeria, on 10 July; but, six days later, sailed to Naples. After loading operations there, she switched to an anchorage at Castellamare, Italy, on 2 August. Here, she embarked personnel of the 36th Division and proceeded to sea on the 13th for the assault in southern France. On the morning of 15 August, her crew commenced discharging her cargo and sending it to the beaches. The next day, after finishing the delivery of cargo, she received casualties on board and embarked 13 German prisoners of war before getting underway at 2100 to return to Naples.
For the next two months, Achernar continued making trips from Naples and Oran to points along the southern coast of France. On 25 October, she sailed from Oran westward through the Strait of Gibraltar towards the United States. She arrived at Hampton Roads on 8 November and underwent repairs and overhaul at the Norfolk Navy Yard. On 7 December, Achernar got underway for a brief period of trials and exercises in Chesapeake Bay. The ship returned to Norfolk on 11 December, took on cargo, and got underway on 18 December. She transited the Panama Canal on Christmas Day 1944 and arrived at Pearl Harbor on 10 January 1945.
Following tactical maneuvers off Oahu from 17 to 19 January, the cargo ship began loading cargo on 12 February and put to sea on the 18th. Achernar stopped at Eniwetok on 26 February, Kossol Roads on 4 March, and anchored in San Pedro Bay, Philippine Islands, from 15 to 20 March, before arriving off Okinawa on 1 April to support the seizure of that key island. At 0043 the next day, a Japanese suicide plane hit the attack cargo ship's starboard side; and, almost simultaneously, a bomb exploded on her port side. Fires broke out, and the ship began listing slightly to port. Achernar lost five crew members killed and 41 injured.
By 0100, the fires were out and the list had been corrected. At 1525, the battered ship transferred her casualties to Solace (AH-5) and proceeded to anchor off Hagushi beach, where temporary repairs began. On the morning of 3 April, Achernar moved to Kerama Retto to begin unloading her cargo. She remained at Okinawa until 19 April, when she sailed for the United States via
After American forces had liberated the territory near Inchon and Seoul, elements of the 1st Marine Division and their equipment were loaded on board Achernar for landing on the east coast of Korea at Wonsan. She sailed as part of TG 90.2 and arrived in Wonsan on 25 October. She unloaded her passengers and proceeded to Moji, Japan, arriving there on 31 October. There, she took on men of the 2d Infantry Division for transportation to Wonsan. Following this mission, she returned to Yokosuka on 20 November.
The attack cargo ship was then ordered to report back to the United States. She left Japan on 27 November accompanying Brush (DD-745) and Mansfield (DD-728)—both of which had been damaged by mines—ready to assist them, if necessary. They made brief stops at Midway and Pearl Harbor before reaching San Francisco on 17 December.
Achernar was placed out of commission on 1 July 1963 and transferred to the Maritime Administration. She was reacquired by the Navy on 29 January 1964 but saw no active service before she was transferred to the government of Spain on 2 February 1965. She served the Spanish Navy as Castilla (TA-21) until scrapped in 1982.<ref>Dictionary of American Naval Fighting Ships [http://www.history.navy.mil/danfs/a2-list.htm]</ref>