First flown on 25 October 1939, the Handley Page Halifax was the second four-engined British heavy bomber to enter service, beating its more famous Lancaster stablemate into combat by months. Its first operational sorties hit Le Havre on 10 March 1941; it became the first to bomb Germany, striking Hamburg days later. Over 6,100 were built, and between 1941 and 1945 Halifaxes flew more than 80,000 sorties, dropping over 227,000 tons of bombs—more than a quarter of all RAF tonnage on Germany. Though Air Chief Marshal Harris considered it inferior to the Lancaster, crews and ground staff praised its robust construction and reliability. The Mk III and Mk VI, with Bristol Hercules radials, finally gave the "Halibag" the performance it deserved, serving in Bomber Command, Coastal Command, and special operations until the last was retired in 1952.