The ship was accepted by Commander G. Moralis, RHN, on 16 July 1959 in Long Beach, California, and arrived in Greece on 15 October 1959. She served in the Hellenic Navy as HHMS/HNS Velos (D-16) (Greek: Βέλος, "Arrow"). Velos took part in almost every Greek and NATO exercise and actively participated in the crises with Turkey of the years 1964, 1967, 1974 (Cyprus crisis) and 1987.On 25 May 1973, Velos, under the command of Nikolaos Pappas, while participating in a NATO exercise and in order to protest against the dictatorship in Greece, anchored at Fiumicino, Italy, refusing to return to Greece.
When in patrol with other NATO vessels between Italy and Sardinia (85 nautical miles (157 km) SW of Rome) at midday on 25 May 1973 the captain and the officers had learned by radio that naval officers had been arrested and tortured in Greece. Commander Pappas was a member of a group of democratic officers, loyal to their oath to obey the Constitution and planning to act against the junta. Pappas knew the arrested officers opposed the junta and realised there was no further hope for a movement inside Greece. He decided to act alone to motivate global public opinion.
Pappas mustered the crew on the stern and announced his decision, which was received with enthusiasm. Pappas signaled his intentions to the commander of the squadron and NATO Headquarters, quoting the preamble of the North Atlantic Treaty (founding treaty for NATO) which declares that "all governments ... are determined to safeguard the freedom, common heritage and civilization of their peoples, founded on the principles of democracy, individual liberty and the rule of law". Leaving formation, he sailed for Rome.
That afternoon, he anchored about 3.5 nautical miles (6.5 km) off the coast at Fiumicino. Three officers (Ensigns K. Gkortzis, K. Mataragkas, G. Stratos) went ashore in a whaleboat. From Fiumicino Airport they telephoned the international press agencies to inform them of the situation in Greece and the presence of the destroyer. They arranged for a press conference to be held the next day by Commander Pappas. This action sparked international interest in the situation in Greece. The captain, six officers, and twenty-five petty officers requested asylum and remained in Italy as political refugees. Initially, the entire crew wished to follow their captain (170 men signed a request), but they were advised (and some ordered) by their officers to remain on board because of the fear of retaliation by regime against their families. The men were told to return to Greece and inform their families and friends about what had happened. Velos returned to Greece a month later with a replacement crew, and the refugees continued the struggle against the dictatorship. After the fall of the junta on (24 July 1974), all of the officers and petty officers returned to the Navy. Commander Pappas reached the rank of Vice Admiral and served as the Chief of the Hellenic Navy General Staff from 1982 to 1986.
Velos was decommissioned on 26 February 1991, having sailed 362,622 nautical miles (671,576 km) in her 48-year career. In 1994 the Hellenic Navy General Staff declared her a Museum of the Struggle against the Dictatorship. The ship, then anchored at Poros Naval Base, was transferred on 14 December 2000 to Salamis Naval Base for maintenance and restoration work in order to be converted into a visitable naval museum. Since 26 June 2002 she has been anchored in the Park of Maritime Tradition at Faliron near Athens. Velos is regarded as still in commission.