The Aasen mortar (Mortier Aasen) was a 3.5-inch (88.9-mm) gun-mortar (or bomb thrower under classification of the time). The Aasen was invented in France in 1915 by Nils Aasen, an arms designer of Norwegian descent. It was adopted by the Russian Empire in 1915-1916, and was used during the First World War.