BAPAlmirante Grau is a cruiser that served in the Royal Netherlands and Peruvian navies. Completed for the Dutch in 1953 as HNLMS De Ruyter, she was acquired by Peru in 1973 and served as fleet flagship. Almirante Grau underwent a major modernization program between 1985 and 1988 during which she was fitted with new weapons and electronics. She was the last gun cruiser in service in any navy before being decommissioned on 26 September 2017. In 2019, it was announced that she would be preserved as a museum ship.
In Dutch service both ships participated in several NATO exercises, and were frequently used as flagships for different naval task forces. Between 1962 and 1964, De Zeven Provinciën underwent a refit which included the removal of the two aft turrets and the installation of a RIM-2 TerrierSAM system, but lack of funds precluded the same modifications from being carried out in De Ruyter. After two decades in service, she was decommissioned on 16 October 1972.
The Peruvian Navy bought De Ruyter on 7 March 1973 as a counter to the acquisition of the Swedish cruiser by the Chilean Navy. Commissioned on 23 May 1973 as Almirante Grau, in honor of the Peruvian AdmiralMiguel Grau, the ship arrived at her new homeport of Callao on 11 July 1973. She was designated fleet flagship in succession to another cruiser of the same name, which was renamed.
Modernization
From 1985 until 1988, she underwent a major modernization program by Amsterdam Naval Services at its shipyard in Amsterdam, during which she was denominated Proyecto de Modernización 01 or PM-01. Her role as flagship was assumed by her sistership as Almirante Grau. Both ships regained their former names when the former De Ruyter returned to Callao on 15 February 1988. The upgrade program carried out in the Netherlands included the following:
Fitting of the Signaal SEWACO Foresee PE combat management system
Two OTO Melara Twin 40L70 DARDO compact gun mountings were fitted in 1996, replacing four single Bofors 40/70 mm gun mountings
The LW-08 radar was later replaced by an AN/SPS-6, the former being installed in the frigate in 2003.
Decommissioning
Almirante Grau was decommissioned on 26 September 2017. She was the last gun cruiser in service in any navy, although its main armament was supplemented with Otomat anti-ship missiles. She was replaced by the BAP Montero, now known as BAP Almirante Grau. On August 9 2019, the Peruvian Navy announced that she would be preserved as a museum ship in Lima.