When World War II broke out in September 1939, neither the Axis, nor the Allied air forces were equipped with aircraft specifically designed for the night fighting role. It was Britain which led the way in pioneering night fighters to intercept enemy bombers. The Boulton Paul Defiant was an early design which was to be eclipsed by the Bristol Beaufighter and the de Havilland Mosquito in its highly effective night fighter variant. The German also used two-engined heavy fighters for night interception missions; aircraft such as the Messerschmitt Bf 110 or the Messerschmitt Me 410 turned out to be reliable and rugged battle horses of the night, intercepting Allied bombers on their way to bomb German cities.
While the RAF was conducting experiments with rudi entary airborne radar in a handful of obsolescent Bristol Blenheims, the Bristol aircraft company was hard at work developing the Bristol Beaufighter, the world’s first dedicated night-fighter to carry radar, produced entirely on their own initiative. This entered service during the Battle of Britain and first saw combat in the German night Blitz of 1940-1. From these small beginnings came an entirely new science of aircraft interception that has continued to advance ever since: the science of locating the enemy on ground radar, guiding the fighter towards its target by means of ground controllers and, eventually, vising airborne radar, closing to within range of the fighter’s own weapons for the kill. Although more within the scope of the bombers’ operations, the night fighter crews had to contend with a growing, parallel science of countermeasures, as the bombers began to include equipment able to blind the ground radar and to provide warning of the approach of a night-fighter.
German ingenuity also produced highly efficient night fighter adaptations of the Messerschmitt Bf 110 and Junkers Ju 88; these two aircraft, together with the excellent Heinkel He 219, provided the backbone of the Reich’s night-fighter defence between 1942 and 1945. Not surprisingly, with so many RAF heavy bombers operating almost nightly over Europe during this period, there came onto the scene numerous Luftwaffe night fighter pilots whose individual victory scores far eclipsed any achievements of their Allied counterparts, it being fairly commonplace for German pilots to destroy four or more Avro Lancasters and Handley Page Halifaxes on a single sortie; once they had entered the great bomber stream their victory bag was limited only by their use of ammunition and fuel. Moreover, the development of the upward-firing cannon (not to mention fairly efficient airborne radar) enabled the Germans to destroy RAF bombers in such a way that the British did not know what had hit them.
Elsewhere, with concerted night operations conducted on a much lesser scale until the onset of the great American night offensive against Japan in 1944, night fighting demanded less attention to sophisticated equipment and tactics than in Europe, although these were quickly introduced when the Boeing B-29 started operations. By and large, during the first two years of the Pacific War, neither Japan nor the United States engaged in significant night bombing, and accordingly did little until 1943 to introduce specialist night-fighters, the Douglas P-70 (though widely employed) being unequivocally a makeshift adaptation of a light bomber.
