By adding 367 training aircraft, British Air Marshal Harris managed to mount the first thousand-plane raid against Germany (the actual count was 1,046), Operation Millennium. Originally targeted for Hamburg, it was switched to Köln due to weather. Over 1,400 tons of explosives were dropped on that city during the night of 30-31 May 1942, killing 500, injuring 5,000, and making nearly 60,000 homeless. 40 British bombers failed to return. The German government estimated that Köln received 900 tons of high explosive and 110,000 incendiary bombs, and about 400 were killed
