Admiral Pereira da Silva-class frigate

The Admiral Pereira da Silva class of frigates, also known as Admiral-class frigates, were in the service of the Portuguese Navy between 1966 and 1985. The class was based on the Dealey-class destroyer escort of the United States Navy. The three ships of the class were built in Portugal, in the Lisnave shipyards and the shipyards of Viana do Castelo.

Admiral Magalhães Correia underway.
Class overview
Name:	Admiral Pereira da Silva class
Builders:	Lisnave - Lisbon ENVC - Viana do Castelo
Operators:	Portugal
Preceded by:	Pacheco Pereira class
Succeeded by:	João Belo class
Built:	1962–1968
In commission:	1966–1989
Planned:	3
Completed:	3
Retired:	3
General characteristics
Type:	Frigate
Displacement:	1,914 long tons (1,945 t)
Length:	95.6 m (314 ft)
Beam:	11.7 m (38 ft)
Draft:	5.5 m (18 ft)
Propulsion:	2 × Foster-Wheeler boilers 1 × De Laval geared turbine 15,000 kW (20,000 shp) 1 shaft
Speed:	27 knots (50 km/h; 31 mph)
Complement:	170
Armament:	2 × Mk 33 76 mm (3 in) guns 2 × triple 533 mm (21 in) torpedo tubes 2 × Hedgehog anti-submarine mortar 2 × DCT (K-guns)

Construction was the victim of numerous problems, among which, it highlighted the difficulty of Portuguese shipyards to build ships with modern sophisticated systems. The construction of the ships was part of the effort of Portugal in owning modern frigates. The frigates they owned at the time, the Pacheco Pereira-class frigates, were of World War II vintage, bought second hand from the United Kingdom and were obsolete.

The Admiral Pereira da Silva class were too small for helicopters and had ASW sensors that did not perform well in bad weather. Portugal could not build large ships due to a shortage of funds. Conversion was ruled out and they were eventually replaced by the Vasco da Gama class. The Portuguese Navy never thought much of these ships and never modernized them and took them out of service well before the end of their useful lives.

In order to share in overseas action the João Belo-class frigates were later built in Pereira da Silva.

These ships specialized in anti-submarine warfare, being designed to operate in the North Atlantic, against the Soviet threat. It was expected to be upgraded with more powerful weapons facilities, including anti-ship missiles, but this never happened.