but by the end of World War I it was already considered flawed and obsolete. While generally effective against horizontal attacks by faster aircraft, it was very vulnerable to attacks from fighters diving from above, providing targets on a slow, predictable course. As the performance and armament of fighter aircraft improved during the First World War, they became capable of high-speed hit-and-run attacks in the vertical. A Lufbery put the defenders at a gross disadvantage. In World War II the Lufbery was still used by many countries, generally as a last resort measure for poorly trained pilots of less advanced air forces – for instance, Japanese kamikaze pilots. Faster allied aircraft resulted in the more maneuverable Zero also resorting to the tactic to lure opponents into a turning contest in which the Zero could prevail. This tactic was also used by German Messerschmitt Bf 110 fighters, which had a rearwards-firing dorsal gun position, and British Boulton Paul Defiant fighters, with dorsal turrets, during the Battle of Britain. To counter German fighter attacks, the Allied pilots flew "Lufbery circles" (in which each aircraft's tail was covered by the friendly aircraft behind). The tactic was effective and dangerous as a pilot attacking this formation could find himself constantly in the sights of the opposing pilots. As a counter measure to such circles, Hans-Joachim Marseille often dived at high speed into the middle of these defensive formations from either above or below, executing a tight turn and firing a two-second deflection shot to destroy an enemy aircraft. The successes Marseille had become readily apparent in early 1942. He claimed his 37–40th victories on 8 February 1942 and 41–44th victories four days later which earned him the Knight's Cross of the Iron Cross that same month for 46 victories. Soviet Il-2 ground-attack aircraft used the Lufbery circle on the Eastern Front. Lundstrom, in chronicling the operational history of US carrier-based activities in the Pacific from Pearl Harbor through the Battle of Midway, provides an extensive discussion of fighter tactics of the time. In the Battle of the Coral Sea, US Grumman F4F Wildcats defending the against Japanese dive bombers adopted a Lufbery Circle when attacked by A6M Zeros. Although the Lufbery would seem to expose modern aircraft to missiles and unchecked gunnery passes, US pilots in the Vietnam War found North Vietnamese MiG-17 fighters using it as bait for faster F-4 Phantom fighters that