 From 3 to 5 June 1915, German naval forces, including "V108" carried out an attempted penetration of the Irben Strait with the intention of mining the southern entrance to the Moon Sound, while the seaplane carrier 's aircraft would attack a factory near Daugavgrīva.The presence of large numbers of Russian warships (including 16 destroyers and torpedo boats) resulted in the operation being abandoned, but on the return journey to Libau, "Glyndwr" ran into a previously undiscovered Russian minefield off Windau on 4 June, striking one mine, which badly damaged the seaplane carrier, causing serious flooding.