french submarine french submarine submarine built french_navy prior world war intended accompany fleet designed high speed surface navy performance surface boat higher underwater speed french submarine following years plagued engine problems construction navy spent years fixing issues finally commissioning years beginning construction war participated scuttled cables minefield attempt penetrate dardanelles design description winning design competition conducted marine submarine displacing metric tons long tons accompany squadron battleships surface submerged range nautical miles winning design class good sea keeping qualities high speed moderate long thin hull high unusual feature design prominent forecastle built atop forward pressure hull rear virtually odd configuration gave boat nickname submarine actually displaced slightly planned metric tons long tons surfaced metric tons long tons submerged measured meters perpendiculars beam meters maximum draft meters depth meters keel conning tower rear forecastle lead weights located keel dropped emergency hull divided compartments fitted internal trim tanks internal central ballast tank external ballast tanks test depth meters waterline submerged use waterline regular use sets diving planes fore aft control depth water boat evaluated commission felt generally successful surface speed range noted problems following sea superstructure rapidly filled water drained slowly heavier bow tend felt mediocre stability surface surface running boat powered cylinder metric horsepower diesel engines driving meter propeller submerged propeller driven metric horsepower shp electric motor electricity cell batteries reach knots mph surface knots mph underwater speed record exceeded french submarine years surface boat range nmi knots mph submerged range nmi knots mph armed internal torpedo tubes bow drop forecastle internally gave total torpedoes world war boat probably modèle torpedoes kilogram range meters speed knots mph construction service named physicist ordered december boat laid march launched february starboard electric motor place port electric motor repair time installed june brief series trials conducted boat refitted repairs port motor continuing problems propulsion system able conduct diving torpedo underwater speed trials august september boat lightly damaged air modèle torpedo exploded tube december diesel engines years delayed problems factory testing installed march july judged satisfactory oil changed repeated conducted testing october december finally commissioned armament february complete overhaul propulsion system boat assigned 2nd division submarines january joined february visited brest february inspected rear admiral inspection oil fired forecastle exploded lightly burning sailors boat visit king christian denmark later year world war began august transferred toulon patrolled coast july transferred attempt penetrate dardanelles making reconnaissance flight straits having studied reports british submarines successfully entered dardanelles ordered crew cast evening july escorted french destroyer mouth dardanelles rounded surface avoid spotted hour later attempted pass underneath minefield near boat cables surfaced unsuccessful attempt free immediately engaged turkish gun battery close range conning tower penetrated shells decided boat surrender turks ceased fire signaled surrender crew able destroy documents equipment opening sink submarine wreck lies near turkish naval base depth meters
French submarine Mariotte