First Spanish S-80 Plus submarine starts sea trials

The Spanish Navy's first S-80 Plus SSK, Isaac Peral (S-81), sets out for initial sea trials on 27 May. (Navantia)

The first of the Spanish Navy's new class of S-80 Plus diesel-electric submarines (SSKs) has started initial sea trials.

First-in-class Isaac Peral (S-81) was put to sea for the first time from state-owned shipbuilder Navantia's facilities in Cartagena, where the boat was built and launched, on 27 May.

Navantia is building four S-80 Plus submarines for the Spanish Navy under a contract awarded in 2004. The boats are intended to replace the Spanish Navy's Galerna (Agosta)-class (S-70) SSKs.

Laid down in 2007 and launched in 2021 following multiple delays, Isaac Peral is on track to be handed over in 2023. Under current planning, its delivery will be followed by that of Narciso de Monturiol (S-82) in 2024, Cosme García (S-83) around early 2026, and Mateo García de los Reyes (S-84) around mid-2027.

The S-80 Plus class will have a submerged displacement of around 3,000 tonnes, with an overall length of 80.8 m, and a top speed of 19 kt dived and 12 kt surfaced. They will be equipped with the new Bio-Ethanol Stealth Technologies (BEST) air independent propulsion (AIP) system, which will provide the submarines with an endurance of up to three weeks at 4 kt.

The AIP system completed its final tests in February 2020 following developmental delays and, as a result, the first submarine to be fitted with the system was Cosme García.Isaac Peral and Narciso de Monturiol will have the system retrofitted when they undergo their first major overhauls.