The Serrano class was a series of six destroyers, built to a British design, which served with the Chilean Navy from 1928 to 1967. In 1927 Chile ordered the Serrano class from John I. Thornycroft & Company in the United Kingdom at the cost of £230,000 for each ship to enhance the Chilean Navy's ability to patrol its extensive coastline. The six vessels were completed by 1929. Serrano, Orella and Hyatt were equipped for minelaying, and Aldea, Riquelme and Videla for minesweeping. Because of weak hull construction the ships had been assessed unsuitable for service along the southern Chilean coast, where it was necessary to use older ships of instead. The destroyers remained in service until the mid-1960s. Design and description Due to its longstanding relationship with the United Kingdom and the quality of British destroyer designs at the time, Chile opted for the John I. Thornycroft & Company option in an international competition to build the Chilean Navy new destroyers. The design followed a standard British layout, but was reduced in size and power. The destroyers had a standard displacement of and were at full load. They were long overall and between perpendiculars with a beam of and a mean draught of . The destroyers were propelled by two shafts turned by Parsons-type geared turbines rated at . These in turn were powered by steam from three Thornycroft boilers. The vessels had a maximum speed of and carried of fuel oil. They had a complement of 130 officers and ratings. During sea trials, all six destroyers exceeded their designed speed by . The Serrano class was armed with three single /45 calibre guns with half-height gun shields. The lack of a fourth gun on the quarterdeck allowed the destroyers to be fitted with minelaying or minesweeping gear. Serrano, Orella and Hyatt were fitted for minelaying, while Riquelme, Aldea and Videla were fitted for minesweeping. For secondary armament for anti-aircraft (AA) defence, the Serrano class was fitted with a single /40 AA gun and three machine guns. The destroyers also had two triple-mounted torpedo tubes for torpedoes. They were fitted with two depth charge throwers for anti-submarine warfare (ASW). Refit The Serrano class underwent very little modification during their service lives. In the first 25 years of service, the only changes was the removal of the mainmast and the addition of single-mounted Oerlikon cannon for AA defence. In the mid-1950s,