From September 30 to October 8, 2019, the Andromeda tripartite minehunter (CMT) was deployed in an area from Cherbourg (50) to Cayeux (80) for a mine warfare mission. The Navy acts daily to secure the French coast and the seabed. This mission is part of regular deployments of CMTs in the Channel and the North Sea to detect, neutralize or destroy unexploded ordnance at sea.
Tripartite-Class Andromède Minehunter from the French Navy (Picture source: French Ministry of Defence)
On September 30, 2019, the crew of CMT Andromède treated a Luft Marine Bomb (LMB - German mine, the most common in the Channel) off Le Havre coast for 850 kg TNT equivalent. This bomb was discovered on July 26th by an amateur diver.
From October 2 to 3, 2019, Andromeda then treated two US bombs representing respectively 200 kg and 740 kg of TNT equivalent, as well as a UK bomb of 65 kg of TNT equivalent. These three bombs were discovered on 23 August by the ship Hermine Bretagne off the Tréport coast.
Tuesday, October 8, 2019, finally, a shell of 270 mm was discovered off Le Havre coast and treated the same day for 55 kg TNT equivalent.
On the balance sheet of this mission, Andromeda will have neutralized 5 historic vehicles representing 1,910 tons of TNT equivalent. Mine hunters regularly operate on the Channel and the North Sea coast to secure approaches to certain ports but also to neutralize gear discovered by third parties (divers, fishermen, etc.). They sweep the seabed using their sonar, before sending divers or a robot to confirm the presence of gear and neutralize it. These mine hunters generally handle less gear, but much larger size such as LMB.
In the Channel and the North Sea in 2018, the joint action of the group of mine-clearing divers and the tripartite mine-hunters of the French Navy destroyed 922 historic vessels (at sea and on the foreshore), which represented 27028 kg equivalent TNT.
