During the invasion of France in May 1940, the Stuka proved as terrifying as it had in Poland, helping to bring about the quick collapse of French resistance. However, this was the high tide of the Stuka. During the Battle of Britain over the summer of 1940, the Ju-87 proved far too vulnerable to British Royal Air Force (RAF) fighters. One out of five Stukas was shot down and the type was withdrawn from the effort on 19 August 1940. There had been a faction in the Luftwaffe that had recognized even before the outbreak of war that the Stuka was an obsolescent aircraft and likely to suffer heavily in the face of effective air opposition. Reichsmarshal Hermann Goering, head of the Luftwaffe, had sided with the advocates of the Stuka, but now the beliefs of the doubters were starting to prove justified. The writing was on the wall for the Ju-87, though its career was far from over. After the Stuka's bloodying in the Battle of Britain, it went on to achieve its former successes in the Mediterranean theater. Stukas badly damaged the Royal Navy carrier HMS ILLUSTRIOUS on 10 January 1941, and sank the cruiser HMS SOUTHAMPTON on 11 January. The Ju-87 also put in very useful service in the capture of the Balkans and Crete in the spring of 1941. Stukas devastated Royal Navy vessels during the Crete campaign, helping to send the cruiser HMS GLOUCESTER to the bottom; also sinking the destroyers GREYHOUND, KELLEY, and KASHMIR; and badly damaging several other RN ships.
The Ju-87 also proved highly effective in North Africa, at least initially. With the invasion of the Soviet Union in the summer of 1941, the Stuka was as destructive as ever, leading the Blitzkrieg deep into the USSR while Red air power was completely crushed. Red Army troops nicknamed it the "Musician" or "Screecher". At that time, Junkers was working on the definitive "Ju-87D" series. The initial "Ju-87D-1" subvariant featured a Jumo 211J-1 engine with 1,045 kW (1,400 HP), driving a new VS-11 propeller. The new engine permitted a much cleaner installation than its predecessors, and the airframe was redesigned accordingly with a new engine cooling scheme, eliminating the older "broken nose" appearance of the Stuka. An entirely new canopy with better aerodynamics was fitted; the main landing gear fairings were reduced in size and tidied up. The fairings would actually be generally removed in service, since they didn't provide much improvement in speed and were a nuisance in muddy field operations. The tailfin was once again enlarged. Greater engine power also permitted more protective armor and fuel capacity, with the Ju-87D-1 featuring the outer wing tanks pioneered by the Ju-87R series. The Ju-87D-1 retained the twin fixed forward MG-17 guns, but replaced the single MG-15 gun in the rear with twin MG-81 guns of the same caliber, ganged together side-by-side on a common flexible mount, for a total of four guns. The MG-81 had a faster rate of fire than the MG-15, and had belt instead of magazine feed. (Very early production apparently had twin rear MG-17 guns instead.)
The Ju-87D-1 could carry a 1,800 kilogram (3,970 pound) bomb over short ranges, and the airframe and bomb crutch were reinforced appropriately. A more typical bombload was a 1,000 kilogram (2,200 pound) bomb on the crutch and two 50 kilogram (110 pound) bombs under each wing, though when used in the close-support role the wings were usually fitted with "Waffenbehaelter (weapons containers)", including a container with six MG-81 machines guns, or a container with twin 20 millimeter MG-FF cannon. As with the Hs-123, cluster munitions with butterfly bombs were also a popular weapon for schlacht missions; the container was released and promptly disintegrated, to scatter its munitions over a wide area.
The Ju-87D-1 began to replace the Ju-87B-2 in production in mid-1942 and was put to use in combat in the East and in North Africa (in the form of the "Ju-87D-1/Trop" modification). A similar variant, the "Ju-87D-2", was built in parallel, differing only in having a strengthened rear fuselage and a stronger tailwheel with a glider tow attachment, to be used in North Africa and the Mediterranean. Production was heavy enough to allow the D-series to replace the less capable B-series in frontline units. The D-series was mostly used in the close-support role, since it was tough and could carry and deliver a lethal warload, though it had to dodge enemy fighters by hiding at low level if fighter cover wasn't available. By this time, the sunshine days of the Stuka were clearly over. In the first year of the war in the East the Red Air Force had been ineffective, but by mid-1942 Soviet air power was beginning to recover. At the same time, Allied air power in North Africa was beginning to make itself painfully felt against the Ju-87. By 1943 the Stuka was clearly on the defensive on all fronts, unable to survive in the face of effective fighter opposition.
The D-series Stuka had been regarded as the end of the line, an interim solution to be manufactured until something better was available. Production of the Stuka had tapered off through 1941, with a total of only 476 Stukas of all types delivered in that year. Unfortunately for the Reich, it quickly became apparent that nothing better was going to be available any time soon. The planned replacement, the Messerschmitt Me-210 twin-engine heavy fighter and attack aircraft, turned out to be almost completely "snakebitten", requiring a long time and a lot of effort to work out its bugs. It was ultimately produced in relatively small numbers as the much more workable "Me-410", but it was a case of too little and much too late. Stuka production ramped back up again, heavily, in 1942, with 917 D-series machines delivered; 1,844 were delivered in 1943.
Manufacturing had moved on to the "Ju-87D-3" in late 1942, with this variant featured improved armor protection to optimize for the schlacht role. It did retain the underwing dive brakes, but had no bomb crutch and no sirens. Some Ju-87D-3s were converted to "Ju-87D-4" torpedo bombers, but they were not used operationally and were later converted back to Ju-87D-3 configuration. The Ju-87D-3 was used in experiments with personnel pods, with one such pod carried on the top of each wing outboard of the landing gear. Two people could ride in tandem in each pod, and in principle the pods could be released in a shallow dive, to deploy parachutes for a soft landing. The whole scheme was questionable and though the Stuka was evaluated with the pods, apparently they were never paradropped. Since the Stuka had undergone the "weight creep" that typically afflicts combat aircraft over their evolution, its wing loading had become unacceptable, and in early 1943 production moved on in turn to the "Ju-87D-5", which featured distinctive "pointed" extended wingtips to improve handling, as well as the jettisonable landing gear developed for the Ju-87C series. The dive brakes were deleted after initial Ju-87D-5 production since it was used almost exclusively in the schlacht role. The two forward-firing MG-17 machine guns were also replaced with twin MG-151/20 20 millimeter cannon.
Confronted with a hostile air environment, by mid-1943 the Stuka was limited mostly to night operations. The Ju-87D-5 had no particular optimizations for flying at night, with pilots coming in low and slow and dropping antipersonnel bombs on clusters of incautious Allied troops. The Luftwaffe learned this trick from the Soviets, who had become fond of using little Po-2 biplanes on such harassment raids earlier in the war. Although a "Ju-87D-6" subvariant was planned, with the focus apparently being the simplification of manufacturing, it was not built. The next variant, the "Ju-87D-7", was a Ju-87D-5 with night flight instrumentation and long flame-damper exhausts to hide the exhaust glow from the pilot or potential enemies. The Ju-87D-7 also featured a further uprated Jumo 211P engine with 1,118 kW (1,500 HP). There was also a "Ju-87D-8" variant, which was a conversion of the Ju-87D-5 to Ju-87D-7 specification. A "Ju-87E" torpedo-bomber was considered, but was cancelled after Germany gave up work on aircraft carriers in early 1943. The D-series Stukas were the last new-build Ju-87s, with the last of them rolled out in September 1944. Total production of all variants amounted to over 5,700 machines
Source:
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