From: Dictionary of American Naval Fighting Ships, Vol.VI p 142
Cities in Maryland and Connecticut.
Rockville was laid down as PCER--851, patrol craft escort rescue, on 18 October 1943 by the Pullman Standard Car Co., Chicago, Ill.: launched 22 February 1944; and commissioned on 15 May 1944, Lt. Comdr. Frank S. Bayley in command.
Following shakedown, PCER--851 , built as a medical rescue ship complete with a surgery, X-ray equipment, 65 hospital beds and an 11-man medical staff, reported for duty in TG 26.1, at Bermuda, on 10 July 1944. Into August, she patrolled in the Bermuda area ; escorted submarines between Norfolk and the British West Indies ; and carried prisoners from U--505, captured by a hunter-killer task group built around Guadalcanal (CVE--60) (q.v.), from Bermuda to Newport News.
On 20 August, PCER--851 got underway for the Pacific. She reported to ComServPac at Pearl Harbor on 15 September; took on more medical equipment ; embarked additional medical personnel ; and sailed west on the 21st.
In October she arrived at Milne Bay, Papua, and pushed on to Manus, whence, on the 11th, she sailed for Leyte Gulf in TU 79.11.3.
En route, she screened the transports. On the 20th, she stood off the Dulag beaches to receive casualties. After the landings she remained in the Dulag area until the 25th, when, as Japanese air raids increased, she was ordered to Tacloban to join TG 78.2. In the afternoon, shrapnel hit and exploded a 20mm. magazine. Four men were injured.
Through November, the PCER continued her "casualty care" mission in the Leyte Gulf area. In December, she accompanied forces to Ormoc Bay ; then joined TG 78.3 to act as rescue and evacuation ship for the Mindoro invasion. Holed at the waterline en route, she splashed one Japanese plane; gave assistance in fighting fires; and rescued survivors of sunken ships. Arriving at the target on the 15th, she got underway the same day to return to Leyte, whence she continued on to New Guinea. Remaining in the New Guinea-Admiralty Islands area into February, she headed for Saipan on the 3d and arrived on the 11th to stage for the Iwo Jima campaign.
PCER--851 departed for the Volcano Islands on the 15th. Again she performed screening duties en route, and, after arrival, patrolled off the beaches. She remained off Iwo Jima until 1 March, then headed back to Leyte.
On the 27th she departed Leyte for the Ryukyus as a unit of the Southern Attack Force, On 1 April she arrived off Okinawa and at 0610 was "greeted" by a single-engine Japanese plane which attempted to crash the "851", but overshot its target and crashed into the sea some 25 yards astern of the ship.
Through the 5th she patrolled, seeing little action. Then, on the 6th, she began rescuing survivors and taking casualties from ships and landing craft crashed by suicide boats and planes. The crews of LCS--82, Maryland, Laffey, Morrison, and Ingraham were among those aided by the PCER.
On 28 June, PCER--851 departed the Ryukyus. Six days later she put into Saipan, whence she escorted Rockwall to Pearl Harbor. Arriving on the 19th, she was undergoing repairs when hostilities ceased in mid-August.
In mid-October the PCER got underway for the east coast. She arrived at Norfolk in late November. In January 1946 she moved north to New London ; conducted operations for the Underwater Sound Laboratory into March ; then continued on to Boston.
Arriving on the 19th, she was decommissioned and placed in service as a Naval Reserve training ship on 12 April. From then into 1950 she trained reservists of the 1st Naval District. Placed in commission, in reserve in June 1950, she returned to the active list on 22 November 1950, and through that year and most of the next continued to operate primarily in the New England area.
On 15 October 1951, PCER--851 was redesignated EPCER-- 851, experimental patrol craft escort rescue, and 4 days later she departed Boston for Norfolk. Thence, she proceeded to her new homeport, Washington, D.C., and duty with the Naval Research Laboratory.
Fitted with an electronics laboratory and workshop, EPCER--851, named Rockville on 15 February 1956, conducted research operations out of Washington, from Newfoundland to and including the Caribbean, until January 1965. Then homeported at Norfolk, she continued her research operations, in conjunction with representatives of the Western Electric Co., until 1968, when she was ordered inactivated. Rockville was decommissioned and struck from the Navy list on 21 December 1968.
PCER--851 earned three battle stars during World War II.