It has not been established what he was doing early years of his life. Most probably, he fought in the Polish September Campaign and later escaped to Great Britain. In 1940, Ścibior became member of the No. 305 Polish Bomber Squadron () He was pilot of a Vickers Wellington. In 1941, his machine crashed during a mission near Charleroi in Belgium. He managed to survive and found his way to Brussels where after hiding for nine days he was caught by the Nazi Germans and sent to a POW camp.