Real or fake? Dark Photos from Dark5 explores the infamous “Tank Silencer.” These photos are from an artillery range in Meppen, officially known as WTD 91, or Wehr Technische Dienststelle 91, located in the Lower Saxony region of Germany. They show a massive, mounted piece of armament that’s camouflaged and clearly military issue. Is it some type of cannon? Is it something to do with radar? Might it be a decoy that attracts enemy fire away from legitimate military targets? It turns out that the machine in the photo is what the Germans refer to as a “Schalldämpfer,” or a silencer. This giant silencer was purposefully built for an M109G 155mm self-propelled howitzer used by the German Defense Force, or Abwehr. The length of barrel that is encompassed by the silencer sleeve has gas vents drilled into it that allows the propellant gas to escape. This results in some of the energy from the fired rounds being lost as it exits the barrel at less than the speed of sound, reducing reverberations and preventing a deafening sonic boom.