P400-class

The P400 class consists of patrol vessels constructed by Constructions Mécaniques de Normandie for the French Navy. Designed for police operations within Exclusive Economic Zones (EEZ), the final design represented an intermediate configuration between a proposed missile-armed variant and a smaller-crew public service version.

The vessels include an Operational Centre for monitoring surface situations using radar indicators and tracking tables. A hydraulic crane is fitted to support anti-pollution operations and the handling of small craft. Propulsion systems are monitored remotely, and the ships provide 15 days of sea endurance with food supplies for 28 personnel for 20 days. Internal modifications allowed for a compartment used for cargo and personnel, capable of ferrying 20 individuals, or up to 60 for short durations in calm seas. Early service was marked by technical issues involving the reduction gear, transmission, and pistons. The exhaust system was also modified from underwater venting to larger pipes to address water ingress.

The French Navy operated ten P400 vessels between 1986 and 2023. These ships were based in overseas territories to conduct sea monitoring, EEZ security, and humanitarian missions. The first vessel, La Fougueuse, was decommissioned in 2009, while the final unit in French service, La Glorieuse, remained active in New Caledonia until May 2023. The class has been succeeded by modified D'Estienne d'Orves-class ships and the Patrouilleur Outre-mer class.

The design is utilized by several international navies. Gabon operates four vessels, including two original builds and two transferred from the French Navy. Kenya and the Ivory Coast each acquired one former French vessel. The Brazilian Navy operates the Macaé class, which is a derivative of the P400 design.