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. Schnaufer claimed his first aerial victory on their thirteenth combat mission flown one day after the attack on Cologne on the night 1/2 June 1942. Nominally this was the RAF's second 1,000 bomber raid against Germany, although the attacking force actually numbered 956 aircraft. Schnaufer shot down a Handley Page Halifax south of Louvain in Belgium. The aircraft probably was Halifax W1064 from No. 76 Squadron piloted by Sergeant Thomas Robert Augustus West, which was shot down at 01:55 on 2 June 1942 and crashed at Grez-Doiceau, south of Louvain. West and another member of the crew were killed. This victory was achieved by ground-controlled interception through the Kammhuber Line. Once near to the target, Rumpelhardt had visually found the bomber and directed Schnaufer into attack position from below and astern. The Halifax caught on fire after two firing passes. During this mission the Himmelbett flight officer vectored them to a second bomber, a Bristol Blenheim. The attack had to be aborted after Hauptmann (Captain) Walter Ehle shot down the bomber from a more favourable attack position. Shortly before 03:00, they were then flying in the vicinity of Ghent, they spotted another target. Schnaufer made two unsuccessful attacks. During their third attack, which closed the distance to , they were hit by the defensive gunfire. Schnaufer was hit in his left calf, the port engine was burning, the rudder control cables were severed, and an electrical short circuit caused the landing lights to be permanently on. Rumpelhardt and Schnaufer considered bailing out but decided to make an attempt for their home airfield after they managed to put out the flames and restart the engine. While Rumpelhardt made radio contact with the Sint-Truiden airbase, Schnaufer landed the aircraft without rudder control and