Lieutenant Chesterman was commanding a vehicle patrol in the Nad ‘Ali district of Helmand province when the lead vehicle struck an improvised explosive device. As he moved forward to take control of the situation the patrol was engaged by insurgent small arms fire and Lieutenant Chesterman was shot.

Despite the best efforts of his fellow Riflemen at the scene, the Medical Emergency Response Team and the staff at the Bastion Hospital, Lieutenant Chesterman could not be saved.