Álvaro de Bazán-class frigate

The Álvaro de Bazán class, also known as the F100 class, is a class of Aegis combat system-equipped air defence frigates in service with the Spanish Navy. The vessels were built by Spanish shipbuilder Navantia in Ferrol, with the lead ship of the class named for Admiral Álvaro de Bazán.

The ships are fitted with the United States Aegis weapons system allowing them to track hundreds of airborne targets simultaneously as part of its air defence network. The Álvaro de Bazán-class multi-role frigates are one of the few non-US warships to carry the Aegis system and its associated SPY-1D radar. The American Arleigh Burke-class destroyer, Japanese Kongo-class destroyer, Korean Sejong the Great-class destroyer, Australian Hobart-class destroyer, and the Norwegian Fridtjof Nansen-class frigate also use the Aegis system.

When the F-100 was designed, the United States communicated that it was impossible to implement the Aegis system in ships of less than 7000 tons, for this reason, after the construction and tests, the United States Navy congratulated and recognized the capacity of the Spanish ships, in addition to the fact that the radars are higher on the Spanish ships and therefore receive information earlier than U.S. or Japanese ships.

The Álvaro de Bazán-class frigates are the first modern vessels of the Spanish Navy to incorporate ballistic resistant steel in the hull, along with the power plants being mounted on anti-vibration mounts to reduce noise and make them less detectable by submarines. The original contract for four ships was worth €1.683 billion but they ended up costing €1.81 billion. it was estimated that the final vessel, F-105 would cost €834m (~US$1.1bn).

Ships in class
Six ships were originally planned, including Roger de Lauria (F105) and Juan de Austria (F106). These were cancelled but a fifth ship was later added as Cristóbal Colón (F105) (It has some improvements compared to the rest of the frigates of its class).

Export
The class is the basis of the Australian Hobart-class destroyers, previously known as the Air Warfare Destroyer. The Australian government announced in June 2007 that, in partnership with Navantia, three F100 vessels were built for the Royal Australian Navy (RAN) with the first due for delivery in 2014. However, this was delayed until 2017 when lead ship HMAS Hobart (DDG 39) was commissioned. All three ships were in service by 2020.

The Fridtjof Nansen-class frigate of the Royal Norwegian Navy is based on the Álvaro de Bazán-class frigate. Five of these vessels were ordered in 2000. The Norwegian frigates were built by Navantia between 2003 and 2009. Four frigates are still in service with the Norwegian Navy as of 2023.