The Heinkel He 177 Greif (Griffin) was a long-range heavy bomber flown by the Luftwaffe during World War II. The introduction of the He 177 to combat operations was significantly delayed by problems both with the development of its engines and frequent changes to its intended role. Nevertheless, it was the only long-range, heavy bomber to become operational with the Luftwaffe during the conflict. The He 177 had a payload/range capability similar to that of four-engined heavy bombers used by the Allies in the European theatre.