A variant of the 110 was the Bf 110D-1, nicknamed "Dachshund-belly" ("Dackelbauch") because of the fixed, wooden, 1,050 litre (277 U.S. gal) fuel tank fitted under the fuselage. I./ZG 76, based in Norway, was equipped with this version in order to provide air cover for convoys sailing along the Norwegian coast. On 15 August, in the belief that all of the RAF fighter units were concentrated far to the south, "Luftflotte 5" launched its first and only bomber attack against North Eastern England. Seven out of the 21 I.ZG 76 aircraft being used as bomber escorts were destroyed, including that of the "Gruppenkommandeur" ("Group Commander").