On 24 November 1914, de Pass entered a German sap near Festubert, France and destroyed a traverse in the face of the enemy's bombs. He also rescued, under heavy fire, a wounded man who was lying exposed to enemy bullets in the open. The next day, de Pass was killed in a second attempt to capture the sap, which the enemy had re-occupied. He was posthumously awarded the Victoria Cross on 18 February 1915.