After their loss in the Battle of Britain, Luftwaffe generally stopped large daylight bombing raids. However, they still continued “The Blitz” on London and other British cities at night. Ostensibly to destroy industry, but like the Royal Air Force nighttime bombing raids, doing damage to residential and commercial areas much more often than not. On the night of 14 November 1940, the largest Luftwaffe raid to date hit the British city of Coventry.
Just after supper, fifteen modified He-111 bombers, using special radio navigation equipment, dropped marker flares for the follow on bombers. Coventry was thought to be a poor nighttime target for bombers due to the surrounding terrain so it lacked adequate barrage balloons and anti aircraft guns. But the pathfinding bombers mitigated this. Soon after, the first wave of Luftwaffe bombers dropped high explosive bombs and naval mines with parachutes (the shock of landing would simulate the strike of a ship, and because they didn’t make a crater their explosions went generally outward instead of generally upward). These were intended to destroy the water mains, the telephone exchanges, and overwhelm and slow down the first responders, particularly firefighters. The next wave dropped phosphorus and magnesium incendiaries to start large fires which were intended to spread. The next wave dropped antipersonnel bombs to kill any fire fighters that made through the rubble caused by the first wave. In all, 515 German bombers made several sorties through the night against Coventry.
About 2 am on the morning of 15 November, a firestorm developed in the city center. Most of the civilian deaths from the raid came about because this conflagration consumed the oxygen out of the air raid shelters. When the all clear sounded the next morning, 1/3 of Coventry was leveled, and 1/3 more of its buildings were damaged. Civilian casualties were considered “light” as most citizens left the city at night after earlier raids.
The Luftwaffe Raid on Coventry had a number of firsts: it was the first bombing raid to use pathfinder aircraft, the first to use incendiaries, and the first to use “block busting” bombs. The Luftwaffe would continue to bomb British cities for the next two years but would never be able to mass on one like they did on Coventry for various reasons. But Raid on Coventry did set several precedents, precedents that the RAF, and eventually the US Eighth Air Force, would mimic hundreds of times against German cities.