High Quality Content by WIKIPEDIA articles! The Redoutable class submarines were ocean-going submarines of the French Navy during the Second World War. They were officially called "Long patrol submarines" (Fr:Sous-marins de grande patrouille), or "Type 1 submarines". They were also referred to as the 1500 Series, and regarded as being in three sub-classes (Though some French sources recognize only two) The Redoubtable class were generally regarded as successful, being reliable and seaworthy, with a good range and armament. A total of 31 were built, the largest class of submarines built by the French Navy, and comprising one-third of its total submarine force.