HMS Vanguard and Le Triomphant submarine collision HMS Vanguard and Le Triomphant submarine collision The submarines HMS "Vanguard" and "Triomphant" collided in the Atlantic Ocean in the night between 3–4 February 2009. Both are nuclear-powered ballistic missile submarines. The Royal Navy's and the French Navy's both sustained damage, but no injuries or radioactivity releases were reported. At the time of the collision, both vessels were submerged and, according to the UK Ministry of Defence, moving "at very low speed"; both are equipped with active and passive sonar, although only the latter is used on an operational patrol. HMS "Vanguard" was on a routine patrol in the Eastern
French submarine Lagrange in 1921. It was named in honor of the distinguished French eighteenth-century mathematician Joseph-Louis Lagrange. From 1922 to 1923, "Lagrange" underwent a major refit in which it received a new conning tower, bridge and periscope. "Lagrange" served in the Mediterranean Sea until 1935. French submarine Lagrange The French submarine "Lagrange" (Q112) was a "Lagrange"-class submarine built for the French Navy built between 1913 and 1918. It was laid down in the Arsenal de Toulon shipyards and launched on August 12, 1919. "Lagrange" was completed in 1918 but saw no action during World War I and served in the French "Marine