Following the analysis of the Butt Report, the British High Command made a number of decisions in February 1942 that changed the nature of the bomber war against Germany. On 14 February, Air Chief Marshal Norman Bottomley issued the "Area Bombing Directive", which lifted the restrictions placed on the bombers in 1941. Air Chief Marshal Arthur Harris, commonly known as "Bomber" Harris, was appointed commander-in-chief of Bomber Command. These decisions, coupled with the introduction of Gee, a radio navigation system which enabled better target-finding and bombing accuracy, led to the first Allied 1,000 bomber raid. In Operation Millennium, the RAF targeted and bombed Cologne on the night of 30/31 May 1942. Schnaufer did not participate in the missions in defence of Cologne. The "Himmelbett" procedure had limitations in the number of aircraft which can be controlled. Therefore, only the most experienced crews were deployed, and Rumpelhardt and Schnaufer, who had yet to achieve their first aerial victory, were left out. Prior to Operation Millennium, Schnaufer had been appointed "Technischer Offizier" (TO—Technical Officer) on 10 April 1942 and was located at Sint-Truiden again. As a Technical Officer, Schnaufer was responsible for the supervision of all technical aspects such as routine maintenance, servicing and modifications of the "Gruppe". In this role he was no longer a member of the 5. "Staffel" but was then a member of the "Stab" (staff) of II./NJG 1.