Eagle Attack"). As night fell, Sperrle sent Kampfgruppe 100 (Bombing Group 100) to bomb Supermarine Spitfire factory at Castle Bromwich, Birmingham which failed to achieve anything. Sperrle, Kesselring, Grauert and Loerzer were summoned to Karinhall to explain why the operation has been a mess. At the meeting, it was decided to intensify attacks from all directions, including Air Fleet 5 in Norway, when the weather permitted. On the 14 August, Sperrle began a smaller, prolonged, but widely scattered series of attacks on aerodromes and other targets in the western half of England. The attacks were not very effective and earned the Luftflotte a rebuke from Göring. The following day, between midnight and midnight, the Luftwaffe made 1,786 sorties. Conferring with his commanders, Göring condemned the lack of foresight which had sent many bombers of Luftflotte 3 on difficult missions suitable only for experienced picked crews. The Reichsmarshall also deplored the waste of effort caused by choosing targets of no strategic value as 'alternatives' for crews unable to reach their primary objectives. The 15 August became known as "Black Thursday" in the Luftwaffe due to the scale of the fighting and losses. The 18 August 1940—known as The Hardest Day—proved disastrous for Sperrle's air fleet. Luftflotte 3 had poor intelligence; the British airfields the Air Fleet attacked had nothing to do with the battle for air superiority, for they belonged to RAF Coastal Command and Fleet Air Arm. Sperrle and his command remained unaware of the intelligence failures, and as one analyst remarked, they "literally did not know what they were doing. Any grass landing strip with a few buildings around it seemed to warrant a raid." From, the tactical perspective, improper positioning of Sperrle's fighter leaders allowed RAF pilots to mass attacks against isolated elements of dive-bombers, causing heavy losses. On 24 August Göring ordered Sperrle to conduct bombing operations against Liverpool, a major port city. Three days later, he decreed Sperrle's air fleet was to be used for night attacks exclusively and siphoned his fighter units off to Kesselring. 450 tons of bombs damaged the docks and damaged . Twenty-four hours earlier, Sperrle's last major daylight attack for several weeks against Portsmouth was repulsed by Park's 11 Group. On the night of 28 August Luftflotte 3 attacked Liverpool. The night's bombing was reckoned the first major night attack on the United Kingdom. The process was repeated for three nights.