England and their aircraft were at a disadvantage against modern single-engine fighters. On 15 September 1940 the Luftwaffe sent nearly 1,000 aircraft against Greater London. This date became known as the Battle of Britain Day. The Luftwaffe's attacks were repulsed with high losses though London and the Thames Estuary docks were severely damaged. LG 1 were the only wing to report losses to its Bf 110 units. Over the next two days the only recorded activity of ZG 76 was the loss of one aircraft in an accident on 17 September On 24 September Erprobungsgruppe 210 bombed the Woolston factory at Southampton on the water front. 98 people were killed and 40 wounded when the shelter was hit, but little damage occurred to the factory. ZG 76 flew as escort. The bomb-carrying Bf 110s lost one and although ZG 76 avoided losses, four suffered damage to anti-aircraft fire; two of the damaged fell into the Channel. One of the crews was rescued by a Heinkel He 59. Three days later seven Bf 110s from LG 1 and ZG 76 were lost on similar operations over England in the morning. In the afternoon ZG 76 flew missions in the Bristol area. ZG 76 lost one on this date, with another severely damaged in action with No. 17 Squadron. On 5 October ZG 76 escorted the unit to RAF West Malling. Engaged by the famed No. 303 Squadron, ZG 76 suffered no losses but their charges lost two and two damaged. Among the dead was acting group commander of Erprobungsgruppe 210, Werner Weimann. The Bf 110, according to one analyst, has been underestimated in the Battle of Britain historiography. The statistics show Bf 110 pilots' claim-to-loss ratio was more favourable than other fighters of the battle; but German claims were usually exaggerated. German airmen claimed 3,085 British aircraft destroyed during the battle; actual RAF losses were 915. The Battle of Britain was expensive for the Zerstörer wings. The Luftwaffe began the battle with 237 serviceable Bf 110s. They lost 223 in the waging of it, with many units fighting to near extinction. Post-Battle of Britain, Balkans, Mediterranean and Iraq ZG 76 lingered on the Channel and in Scandinavia until late 1940. Stab/ZG 76 became Jagdfliegerführer Norwegen under Grabmann until approximately June 1941, when appears to have been disbanded. I./ZG 76, under the command of Hauptmann Heinrich Graf von Stillfried und Rattonitz, was