Poor weather in early 1918 saw little opportunity for JG I to score, although the unit were in the forefront of defensive fighter operations during the major German offensive launched on 21 March 1918. By April 1918 the formation was flying from Harbonnieres, the most south westerly airfield they were to ultimately occupy. The newly formed RAF however maintained a degree of air superiority, with heavily escorted artillery observation and reconnaissance two-seaters operating effectively over the rapidly moving ground battle below. Most of JG I's victims at this time were the low flying fighter bombers, particularly Sopwith Camels.