Editing Junkers Ju 87 (section)

==Variants==

===Ju 87 A===
[[File:Ju87A 050406-F-1234P-041.jpg|thumb|Formation of Ju 87 A dive-bombers, with the A's characteristic large wheel "trousers", each having one transverse bracing strut]]
The second prototype had a redesigned single vertical stabiliser and a {{cvt|610|PS|hp kW|1}} Jumo 210 A engine installed, and later the Jumo 210Da. The first A series variant, the A-0, was of all-metal construction, with an enclosed cockpit under a "greenhouse" well-framed canopy; bearing twin radio masts on its aft sections, diagonally mounted to either side of the airframe's planform centreline and unique to the -A version. To ease the difficulty of mass production, the leading edge of the wing was straightened out and the [[aileron]]s' two [[Airfoil|aerofoil]] sections had smooth leading and trailing edges. The pilot could adjust the elevator and rudder trim tabs in flight, and the tail was connected to the landing flaps, which were positioned in two parts between the ailerons and fuselage. The A-0 also had a flatter engine cowling, which gave the pilot a much better field of vision. In order for the engine cowling to be flattened, the engine was set down nearly {{convert|0.25|m|in|abbr=on}}. The fuselage was also lowered along with the gunner's position, allowing the gunner a better field of fire.<ref name="Griehl 2001, p. 50">{{harvnb|Griehl|2001|p=50}}</ref>

The RLM ordered seven A-0s initially, but then increased the order to 11. Early in 1937, the A-0 was tested with varied bomb loads. The underpowered Jumo 210A, as pointed out by von Richthofen, was insufficient, and was quickly replaced with the Jumo 210D engine.<ref name="Griehl 2001, p. 50"/>

The A-1 differed from the A-0 only slightly.<ref name="Griehl 2001, p. 52">{{harvnb|Griehl|2001|p=52}}</ref> As well as the installation of the Jumo 210D, the A-1 had two {{cvt|220|L|USgal+impgal}} fuel tanks built into the inner wing, but it was not armoured or protected.<ref name="Griehl 2001, p. 52"/> The A-1 was also intended to be fitted with four {{cvt|7.92|mm|3}} MG 17 machine guns in its wings, but two of these—one per side—were omitted due to weight concerns; the pair that remained were fed a total of 500 rounds of ammunition, stored in the design's characteristic transverse strut-braced, large-planform undercarriage "trousers", not used on the Ju 87B versions and onward. The pilot relied on the Revi C 21C gun sight for the two MG 17s. The gunner had a single {{cvt|7.92|mm|3}} MG 15, with 14 drums of ammunition, each containing 75 rounds. This represented a 150-round increase in this area over the Ju 87 A-0. The A-1 was also fitted with a larger {{convert|3.3|m|ft|abbr=on}} propeller.<ref name="Griehl 2001, p. 52"/>

The Ju 87 was capable of carrying a {{convert|500|kg|lb|abbr=on}} bomb, but only if not carrying the rear gunner/radio operator as, even with the Jumo 210D, the Ju 87 was still underpowered for operations with more than a {{convert|250|kg|lb|abbr=on}} bomb load. All Ju 87 As were restricted to {{convert|250|kg|lb|abbr=on}} weapons (although during the [[Spanish Civil War]] missions were conducted without the gunner).<ref>{{harvnb|Griehl|2001|p=53}}</ref>

The Ju 87 A-2 was retrofitted with the Jumo 210Da fitted with a two-stage [[supercharger]]. The only further significant difference between the A-1 and A-2 was the H-PA-III [[Variable-pitch propeller (aeronautics)|controllable-pitch propeller]].<ref>{{harvnb|Griehl|2001|p=54}}</ref> By mid-1938, 262 Ju 87 As had been produced, 192 from the Junkers factory in Dessau and a further 70 from [[Weser Flugzeugbau]] ("Weserflug" – WFG) in [[Lemwerder]] near Bremen. The new, more powerful, Ju 87B model started to replace the Ju 87A at this time.<ref>{{harvnb|Griehl|2001|p=57}}</ref>

[[File:Het prototype van de Junkers Ju 87 V4 'Stuka' bij de fabrikek in 1936 2157 001-053.jpg|thumb|right|The Ju 87 V4 prototype in 1936.]]
'''Prototypes'''<ref>{{harvnb|Erfurth|2004|p=40}}</ref>
* '''Ju 87 V1''' : W.Nr 4921. Flown on 17 September 1935
* '''Ju 87 V2''' : W.Nr 4922, registration D-IDQR. Flown on 25 February 1936. Flown again as registration D-UHUH on 4 June 1937
* '''Ju 87 V3''' : W.Nr 4923. Flown on 27 March 1936
* '''Ju 87 V4''' : W.Nr 4924. Flown on 20 June 1936
* '''Ju 87 V5''' : W.Nr 4925. Flown on 14 August 1936

'''Production variants'''
* '''Ju 87 A-0''' : Ten pre-production aircraft, powered by a 640&nbsp;PS ({{convert|471|kW|hp|abbr=on|disp=or}}) Jumo 210C engine.<ref name="Erfurth 2004, p. 42">{{harvnb|Erfurth|2004|p=42}}</ref>
* '''Ju 87 A-1''' : Initial production version.
* '''Ju 87 A-2''' : Production version fitted with an improved 680&nbsp;PS ({{convert|500|kW|hp|abbr=on|disp=or}}) Jumo 210E engine.

===Ju 87 B===
[[File:Een met bommen beladen Junkers Ju 87 Stuka op een gecamoufleerde opstelplaats op Fliegerhorst Schiphol (2189-01-25-002).jpg|thumb|left|Junkers Ju 87 B parked at Schiphol airport in the Netherlands, 1940.]]

The Ju 87 B series was to be the first mass-produced variant. A total of six pre-production Ju 87 B-0 were produced, built from Ju 87 A airframes.<ref name="Griehl 2001, p. 63">{{harvnb|Griehl|2001|p=63}}</ref> The first production version was the Ju 87 B-1, with a considerably larger engine, its Jumo 211D generating 1,200&nbsp;PS ({{convert|883|kW|hp|abbr=on|disp=or}}), and completely redesigned fuselage and landing gear, replacing the twin radio masts of the "A" version with a single mast mounted further forward on the "greenhouse" canopy, and much simpler, lighter-weight wheel "spats" used from the -B version onwards, discarding the transverse strut bracing of the "A" version's maingear design. This new design was again tested in Spain, and after proving its abilities there, production was ramped up to 60 per month. As a result, by the outbreak of [[World War II]], the Luftwaffe had 336 Ju 87 B-1s on hand.<ref name="Griehl 2001, p. 61"/>

The B-1 was also fitted with "Lärmgeräte", essentially [[Siren (alarm)|sirens]] driven by propellers with a diameter of {{convert|0.7|m|ft|abbr=on}}<ref name="Griehl 2001, p. 64">{{harvnb|Griehl|2001|p=64}}</ref> The devices caused a loss of 20–25&nbsp;km/h (12–15&nbsp;mph) through drag, and over time the sirens were no longer installed on many units, although they remained in use to various extent. As an alternative, some bombs were fitted with whistles on the fin to produce the noise after release.<ref>{{harvnb|Griehl|2001|pp=64–65}}</ref> The trumpets were a suggestion from Udet, but some authors say the idea originated from [[Adolf Hitler]].<ref name="Boyne 1994, p. 30">{{harvnb|Boyne|1994|p=30}}</ref>

The Ju 87 B-2s that followed had some improvements and were built in several variants that included ski-equipped versions (the B-1 also had this modification)<ref>{{harvnb|Griehl|2001|p=65}}</ref> and at the other end, with a tropical operation kit called the Ju 87 B-2 trop. Italy's [[Regia Aeronautica]] received B-2s and named them the "Picchiatello", while others went to the other members of the [[Axis powers of World War II|Axis]], including Hungary, Bulgaria and Romania. The B-2 also had an oil hydraulic system for closing the [[Aircraft engine controls|cowling flaps]]. This continued in all the later designs.<ref name="Griehl 2001, p. 66">{{harvnb|Griehl|2001|p=66}}</ref>

Production of the Ju 87 B started in 1937. 89 B-1s were to be built at Junkers' factory in Dessau and another 40 at the Weserflug plant in Lemwerder by July 1937. Production would be carried out by the Weserflug company after April 1938, but Junkers continued producing Ju 87 up until March 1940.<ref name="Griehl 2001, p. 68"/>

=== Ju 87 R ===
A long range version of the Ju 87 B was also built, known as the Ju 87 R, the letter being an abbreviation for ''Reichweite'', "(operational) range". They were primarily intended for anti-shipping missions. The Ju 87 R had a B-series airframe with an additional oil tank and fuel lines to the outer wing stations to permit the use of two {{convert|300|L|USgal}} standardised capacity under-wing [[drop tank]]s, used by a wide variety of Luftwaffe aircraft through most of the war. This increased fuel capacity to {{convert|1080|L|USgal}} (500&nbsp;litres in main fuel tank of which 480&nbsp;litres were usable + 600&nbsp;litres from drop tanks). To prevent overload conditions, bomb carrying ability was often restricted to a single {{convert|250|kg|lb|abbr=on}} bomb if the aircraft was fully loaded with fuel.

The Ju 87 R-1 had a B-1 airframe with the exception of a modification in the fuselage which enabled an additional oil tank. This was installed to feed the engine due to the increase in range with the extra fuel tanks.<ref name="Griehl 2001, p. 79">{{harvnb|Griehl|2001|p=79}}</ref>

[[File:Bundesarchiv Bild 101I-567-1523-35A, Italien, Lastensegler DFS 230, Ju 87.jpg|thumb|A Ju-87 towing a [[DFS 230]] over Italy]]
The Ju 87 R-2 had the same airframe as the B-2, and strengthened to ensure it could withstand dives of {{convert|600|km/h|mph|abbr=on}}. The Jumo 211D in-line engine was installed, replacing the R-1s Jumo 211A.<ref name="Griehl 2001, p. 79"/> Due to an increase in overall weight by {{convert|700|kg|lb|abbr=on}}, the Ju 87 R-2 was {{convert|30|km/h|mph|abbr=on}} slower than the Ju 87 B-1 and had a lower service ceiling. The Ju 87 R-2 had an increased range advantage of {{convert|360|km|mi|abbr=on}}.<ref name="Griehl 2001, p. 68">{{harvnb|Griehl|2001|p=68}}</ref> The R-3 and R-4 were the last R variants developed. Only a few were built. The R-3 was an experimental tug for gliders and had an expanded radio system so the crew could communicate with the glider crew by way of the tow rope. The R-4 differed from the R-2 in the Jumo 211J powerplant.<ref name="Griehl 2001, pp. 80-81">{{harvnb|Griehl|2001|pp=80–81}}</ref>

[[File:Bundesarchiv Bild 101I-378-0037-16A, Reichsgebiet, Wartung Ju 87.jpg|thumb|The powerplant; a Jumo 211D installed in a Ju 87 B – the "Lärmgerät" housing is faired over on the maingear leg]]
'''Known prototypes'''<ref name="Griehl 2001, p. 49">{{harvnb|Griehl|2001|p=49}}</ref>
* '''Ju 87 V6''' : W.Nr 0870027. Flown on 14 June 1937 (A-0 to B-0 conversion)
* '''Ju 87 V7''' : W.Nr 0870028. Prototype of the Ju 87B, powered by a 1,000&nbsp;PS ({{convert|735|kW|hp|abbr=on|disp=or}}) Jumo 211A. Flown on 23 August 1937 (A-0 to B-0 conversion)
* '''Ju 87 V8''' : W.Nr 4926. Flown on 11 November 1937
* '''Ju 87 V9''' : W.Nr 4927. Flown on 16 February 1938 as D-IELZ. Flown again as WL-IELZ on 16 October 1939
* '''Ju 87 V15''': W.Nr 0870321. Registration D-IGDK. Destroyed in a crash in 1942.
* '''Ju 87 V16''': W.Nr 0870279. ''Stammkennzeichen'' code of GT+AX.
* '''Ju 87 V17''' and '''Ju 87 V18''' may never have been built.<ref name="Griehl 2001, p. 63"/>

=== Ju 87 C ===
On 18 August 1937, the RLM decided to introduce the Ju 87 Tr(C). The Ju 87 C was intended to be a dive and [[torpedo bomber]] for the [[Kriegsmarine]]. The type was ordered into prototype production and available for testing in January 1938. Testing was given two months and was to begin in February and end in April 1938.<ref name="Griehl 2001, p. 240">{{harvnb|Griehl|2001|p=240}}</ref> The prototype V10 was to be a fixed wing test aircraft, while the following V11 would be modified with [[folding wing]]s. The prototypes were Ju 87 B-0 airframes powered by Jumo 211 A engines.<ref name="Griehl 2001, p. 240"/> Owing to delays, the V10 was not completed until March 1938. It first flew on 17 March and was designated Ju 87 C-1.<ref name="Griehl 2001, p. 240"/> On 12 May, the V11 also flew for the first time. By 15 December 1939, 915 arrested landings on dry land had been made. It was found that the [[arresting gear]] winch was too weak and had to be replaced. Tests showed the average braking distance was {{convert|20|–|35|m|ft}}.<ref name="Griehl 2001, p. 241">{{harvnb|Griehl|2001|p=241}}</ref> The Ju 87 V11 was designated C-0 on 8 October 1938. It was fitted out with standard Ju 87 C-0 equipment and better wing-folding mechanisms. The "carrier Stuka" was to be built at the Weserflug Company's Lemwerder plant between April and July 1940.<ref name="Griehl 2001, p. 242">{{harvnb|Griehl|2001|p=242}}</ref>

Among the "special" equipment of the Ju 87 C was a two-seat rubber [[dinghy]] with a flare gun, signal ammunition and other emergency supplies. A quick fuel dump mechanism and two inflatable 750&nbsp;L (200&nbsp;US gal) bags in each wing and a further two 500&nbsp;L (130&nbsp;US gal) bags in the fuselage enabled the Ju 87 C to remain afloat for up to three days in calm seas.<ref name="Griehl 2001, p. 242"/> On 6 October 1939, with the war already underway, 120 of the planned Ju 87 Tr(C)s on order at that point were cancelled. Despite the cancellation, the tests continued using catapults. The Ju 87 C had a takeoff weight of {{convert|5300|kg|lb|abbr=on}} and a speed of {{convert|133|km/h|mph|abbr=on}} on departure. The Ju 87 could be launched with a SC {{convert|500|kg|lb|abbr=on}} bomb and four SC {{convert|50|kg|lb|abbr=on}} bombs under the fuselage. The C-1 was to have two MG 17s mounted in the wing with a MG 15 operated by the rear gunner. On 18 May 1940, production of the C-1 was switched to the R-1.<ref name="Griehl 2001, p. 243">{{harvnb|Griehl|2001|p=243}}</ref>

'''Known prototypes'''<ref name="Griehl 2001, p. 49"/>
* '''Ju 87 V10''': Registration D-IHFH (changed to ''Stammkennzeichen'' of TK+HD). W.Nr 4928. First flown 17 March 1938
* '''Ju 87 V11''': ''Stammkennzeichen'' of TV+OV. W.Nr 4929. First flown 12 May 1938

=== Ju 87 D ===
Despite the Stuka's vulnerability to enemy fighters having been exposed during the [[Battle of Britain]], the Luftwaffe had no choice but to continue its development, as there was no replacement aircraft in sight.<ref>{{harvnb|Mondey|1996|p=114}}</ref> The result was the D-series. In June 1941, the RLM ordered five prototypes, the Ju 87 V21–25. A [[Daimler-Benz DB 603]] powerplant was to be installed in the Ju 87 D-1, but it did not have the power of the Jumo 211 and performed "poorly" during tests and was dropped.<ref name="Griehl 2001, p. 87">{{harvnb|Griehl|2001|p=87}}</ref> The Ju 87 D-series featured two coolant radiators underneath the inboard sections of the wings, while the oil cooler was relocated to the position formerly occupied by the single, undernose "chin" coolant radiator. The D-series also introduced an aerodynamically refined cockpit with better visibility and space.{{sfn|Griehl|2001|p=95}} Armour protection was increased and a new dual-barrel 7.92&nbsp;mm (.312&nbsp;in) [[MG 81 machine gun|MG 81Z machine gun]] with an extremely high rate of fire was installed in the rear defensive position. Engine power was increased again, the Jumo 211J now delivering 1,420&nbsp;PS ({{convert|1044|kW|hp|abbr=on|disp=or}}).{{sfn|Griehl|2001|p=95}}
Bomb carrying ability was nearly quadrupled from {{convert|500|kg|lb|abbr=on}} in the B-version to {{convert|1800|kg|lb|abbr=on}} in the D-version (max. load for short ranges, overload condition), a typical bomb load ranged from {{convert|500|-|1200|kg|lb|abbr=on}}.<ref name="Griehl 2001, p. 99">{{harvnb|Griehl|2001|p=99}}</ref>

[[File:Bundesarchiv Bild 101I-329-2984-05A, Russland, Junkers Ju 87 Recolored.png|thumb|Ju 87Ds, Soviet Union, January/February 1943]]

The internal fuel capacity of the Ju 87 D was raised to 800&nbsp;L (of which 780&nbsp;L were usable) by adding wing tanks while retaining the option to carry two 300&nbsp;L drop tanks. Tests at [[Rechlin-Lärz Airfield]] revealed it made possible a flight duration of 2 hours and 15 minutes. With an extra two 300&nbsp;L (80&nbsp;US gal) fuel tanks, it could achieve four hours flight time.{{sfn|Griehl|2001|p=95}}

The D-2 was a variant used as a glider tug by converting older D-series airframes. It was intended as the tropical version of the D-1 and had heavier armour to protect the crew from ground fire. The armour reduced its performance and caused the [[Oberkommando der Luftwaffe]] to "place no particular value on the production of the D-2".{{sfn|Griehl|2001|p=95}} The D-3 was an improved D-1 with more armour for its ground-attack role. Some Ju 87 D-3s were designated D-3N or D-3&nbsp;trop and fitted with night or tropical equipment.{{sfn|Griehl|2001|p=95}} The D-4 designation applied to a prototype torpedo-bomber version, which could carry a {{convert|750|–|905|kg|lb|abbr=on}} [[aerial torpedo]] on a PVC 1006 B rack—this setup would have had the capacity to carry the ''Luftorpedo'' LT 850, the German version of the well-proven Japanese [[Type 91 torpedo#Provision of the aerial torpedo technology to Germany|Type 91 aerial torpedo]] of 848&nbsp;kg (1,870&nbsp;lb). The D-4 was to be converted from D-3 airframes and, in place of the carrier-specific Ju 87C series designs, operated from the aircraft carrier ''{{ship|German aircraft carrier|Graf Zeppelin||2}}''.<ref name="Griehl 2001, p. 97">{{harvnb|Griehl|2001|p=97}}</ref> Other modifications included a flame eliminator and, unlike earlier D variants, two 20&nbsp;mm MG 151/20 cannon, while the radio operator/rear gunner's ammunition supply was increased by 1,000 to 2,000 rounds.<ref name="Griehl 2001, p. 98">{{harvnb|Griehl|2001|p=98}}</ref>

[[File:Duitse Junkers Ju 87 "Stuka" 2157 008308.jpg|thumb|right|A pair of Ju 87Ds following a landing with air brakes still deployed.]]
The Ju 87 D-5 was based on the D-3 design and was unique in the Ju 87 series as it had wings 0.6 metres (2&nbsp;ft) longer than previous variants. The two 7.92&nbsp;mm MG&nbsp;17 wing guns were exchanged for more powerful 20&nbsp;mm MG&nbsp;151/20s to better suit the aircraft's ground-attack role. The window in the floor of the cockpit was reinforced and four, rather than the previous three, aileron hinges were installed. Higher diving speeds were obtained of {{convert|650|km/h|mph|abbr=on}} up to {{convert|2000|m|ft|abbr=on}}. The range was recorded as {{convert|715|km|mi|abbr=on}} at ground level and {{convert|835|km|mi|abbr=on}} at {{convert|5000|m|ft|abbr=on}}.<ref name="Griehl 2001, p. 99"/>

The D-6, according to "Operating instructions, works document 2097", was built in limited numbers to train pilots on "rationalised versions". Due to shortages in raw materials, it did not go into mass production.<ref name="Griehl 2001, pp. 101–102"/> The D-7 was another ground attack aircraft based on D-1 airframes upgraded to D-5 standard (armour, wing cannons, extended wing panels), while the D-8 was similar to the D-7 but based on D-3 airframes.<ref name="Griehl 2001, pp. 101–102">{{harvnb|Griehl|2001|pp=101–102}}</ref> The D-7 and D-8 were both were fitted with exhaust flame dampers, and could conduct night operations.<ref name="Griehl 2001, pp. 101–102"/>

Production of the D-1 variant started in 1941 with 495 ordered. These aircraft were delivered between May 1941 and March 1942. The RLM wanted 832 machines produced from February 1941. The Weserflug company was tasked with their production. From June to September 1941, 40 Ju 87 Ds were expected to be built, increasing to 90 thereafter.<ref name="Griehl 2001, p. 102">{{harvnb|Griehl|2001|p=102}}</ref> Various production problems were encountered. One of the planned 48 was produced in July. Of the 25 the RLM hoped for in August 1941, none were delivered.<ref name="Griehl 2001, p. 102"/> In September did the first two of the planned 102 Ju 87s came off the production lines.<ref name="Griehl 2001, p. 103">{{harvnb|Griehl|2001|p=103}}</ref> The shortfalls continued to the end of 1941. During this time, the WFG plant in Lemwerder moved production to Berlin. Over 165 Ju 87s had not been delivered and production was only 23 Ju 87 Ds per month out of the 40 expected. By the spring of 1942 to the end of production in 1944, 3,300 Ju 87s, mostly D-1s, D-2s and D-5s had been manufactured.<ref name="Griehl 2001, p. 103"/>

In January 1943, a variety of Ju 87 Ds became "test beds" for the Ju 87 G variants. At the start of 1943, the coastal Luftwaffe [[Tarnewitz test site|''Erprobungsstelle'' test centre at Tarnewitz]] tested this combination from a static position. ''Oberst'' G. Wolfgang Vorwald noted the experiments were not successful, and suggested the cannon be installed on the [[Messerschmitt Me 410]].<ref name="Griehl 2001, p. 284">{{harvnb|Griehl|2001|p=284}}</ref> Testing continued, and on 31 January 1943, Ju 87 D-1 W.Nr 2552 was tested by ''[[Hauptmann]]'' [[Hans-Karl Stepp]] near the [[Briansk]] training area. Stepp noted the increase in drag, which reduced the aircraft's speed to {{convert|259|km/h|mph|abbr=on}}. Stepp also noted that the aircraft was also less agile than the existing D variants. D-1 and D-3 variants operated in combat with the {{convert|37|mm|in|abbr=on}} BK 37 cannon in 1943.<ref name="Griehl 2001, p. 284"/>

'''Known prototypes'''
* Ju 87 V 21. Registration D-INRF. W.Nr 0870536. Airframe conversion from B-1 to D-1. First flown on 1 March 1941.
* Ju 87 V 22 ''Stammkennzeichen'' of SF+TY. W.Nr 0870540. Also airframe conversion from B-1 to D-1. First flown on 1 March 1941.
* Ju 87 V 23 ''Stammkennzeichen'' of PB+UB. W.Nr 0870542. Also airframe conversion from B-1 to D-1. First flown on 1 March 1941.
* Ju 87 V 24 ''Stammkennzeichen'' of BK+EE. W.Nr 0870544. Also airframe conversion from B-1 to D-1/D-4. First flown on 1 March 1941.
* Ju 87 V 25 ''Stammkennzeichen'' of BK+EF. W.Nr 0870530. Also airframe conversion from B-1 to D-4 trop. First flown on 1 March 1941.
* Ju 87 V 30, the only known prototype of the Ju 87 D-5. W.Nr 2296. First flown on 20 June 1943.
* Ju 87 V 26-28, Ju 87 V 31, and V 42-47 were experiments of unknown variants.<ref name="Griehl 2001, p. 49"/>

=== Ju 87 G ===
[[File:Bundesarchiv Bild 101I-646-5184-26, Russland, Flugzeug Junkers Ju 87 edit 1.jpg|thumb|left|Ju 87 G-1 "''Kanonenvogel''" with its twin Bordkanone {{convert|3.7|cm|in|abbr=on|2}} underwing gun pods]]

With the G variant, the ageing airframe of the Ju 87 found new life as an anti-tank aircraft. This was the final operational version of the Stuka, and was deployed on the Eastern Front. The reversal in German military fortunes after 1943 and the appearance of [[Soviet armoured fighting vehicle production during World War II|huge numbers of well-armoured Soviet tanks]] caused Junkers to adapt the existing design to combat this new threat. The [[Henschel Hs 129]] had proved a potent ground attack weapon, but its large fuel tanks made it vulnerable to enemy fire, prompting the RLM to say, "that in the shortest possible time a replacement of the Hs 129 type must take place."<ref>{{harvnb|Griehl|2001|p=274}}</ref> With Soviet tanks the priority targets, the development of a further variant as a successor to the Ju 87D began in November 1942. On 3 November, Milch raised the question of replacing the Ju 87, or redesigning it altogether. It was decided to keep the design as it was, but the power-plant was upgraded to a [[Junkers Jumo 211#Variants|Junkers Jumo 211J]], and two {{convert|37|mm|in|abbr=on}} cannons were added. The variant was also designed to carry a {{convert|1000|kg|lb|abbr=on}} free-fall bomb load. Furthermore, the armoured protection of the [[Ilyushin Il-2]] ''Sturmovik''{{Efn|a feature pioneered by the 1916–17 origin [[Junkers J.I]] all-metal sesquiplane of World War I [[German Empire|Imperial Germany]]'s [[Luftstreitkräfte]]}} was copied to protect the crew from ground fire now that the Ju 87 would be required to conduct low level attacks.{{sfn|Griehl|2001|pp=274–275}}

[[File:Niemiecki samolot bojowy na polu startowym (2-13035).jpg|thumb|right|Hans-Ulrich Rudel's Ju 87 G-1 in May 1944]]
[[File:Niemiecki samolot bojowy na polu startowym (2-13036).jpg|thumb|left|A technician servicing the 3.7 cm gun pod. The barrel can be seen near the left border of the photo.]]
[[Hans-Ulrich Rudel]], a Stuka ace, had suggested using two [[3.7 cm Flak 18/36/37|37&nbsp;mm (1.46&nbsp;in) Flak 18 guns]], each one in a self-contained under-wing [[gun pod]], as the [[BK 37|''Bordkanone BK 3,7'']], after achieving success against Soviet tanks with the 20&nbsp;mm MG 151/20 cannon. These gun pods were fitted to a Ju 87 D-1, W.Nr 2552. The first flight of the machine took place on 31 January 1943, piloted by Stepp.<ref name="Griehl 2001, p. 284"/> The continuing problems with about two dozen of the Ju 88P-1 and slow development of the [[Henschel Hs 129#Hs 129 B-3|Henschel Hs 129 B-3]], both designs using the large, [[7.5 cm Pak 40]]-based, autoloading Bordkanone 7,5 7.5&nbsp;cm (2.95&nbsp;in) cannon in a conformal gun pod beneath the fuselage, meant the Ju 87G was put into production. In April 1943, the first production Ju 87 G-1s were delivered to front line units.<ref name="Griehl 2001, p. 284"/> The two 37&nbsp;mm (1.46&nbsp;in) [[BK 3,7|''Bordkanone'' BK 3,7]] cannons were mounted in under-wing gun pods, each loaded with two six-round magazines of [[Armor-piercing ammunition#APCR and HVAP|armour-piercing tungsten carbide-cored ammunition]]. With these weapons, the ''Kanonenvogel'' ("cannon-bird"), as it was nicknamed, proved very successful in the hands of Stuka aces such as Rudel. The G-1 was converted from older D-series airframes, retaining the smaller wing, but without the dive brakes. The G-2 was similar to the G-1 except for use of the extended wing of the D-5. 208 G-2s were built and at least a further 22 more were converted from D-3 airframes. Only a handful of production Gs were committed in the [[Battle of Kursk]]. On the opening day of the offensive, Hans-Ulrich Rudel flew the only "official" Ju 87 G, although a significant number of Ju 87 D variants were fitted with the 37&nbsp;mm (1.46&nbsp;in) cannon, and operated as unofficial Ju 87 Gs before the battle. In June 1943, the RLM ordered 20 Ju 87Gs as production variants.<ref name="Griehl 2001, p. 286.">{{harvnb|Griehl|2001|p=286}}</ref>

=== Night-harassment variants ===
The Ju 87 had been used in the [[intruder (air combat)|night intruder]] role in 1940 and 1941 during [[The Blitz]],<ref>{{harvnb|Smith|2011|p=349}}</ref> but the [[Soviet Air Force]] practice of [[Night Witches|harassing German ground forces]] using antiquated [[Polikarpov Po-2]] and [[Polikarpov R-5|R-5]] [[biplane]]s at night to drop flares and fragmentation bombs, inspired the Luftwaffe to form its own ''Störkampfstaffeln'' (harassment squadrons). On 23 July 1942, Junkers offered the Ju 87 B-2, R-2 and R-4s with ''Flammenvernichter'' ("flame eliminators"). On 10 November 1943, the RLM GL/C-E2 Division finally authorised the design in directive No. 1117.<ref>{{harvnb|Griehl|2001|p=209}}</ref>

The need to equip night units and the phasing out of Ju 87s from ground attack groups in favour of the Fw 190, enabled the use of D-5 airframes awaiting repair and D-7 and 8s already in conversion units. The latter variants were either conversions or modified D-1 and D-3 air frames. Adding the necessary equipment, radios and dampeners was a requirement regardless of whether the aircraft was a production D-5 or a D-1 or 3 that had undergone wing changes. The change in designations due to conversions was not readily apparent, for with wing changes, the serial number and designation was applied to the fuselage by the manufacture which remained unaltered by wing changes. Some sub-contractors added an "N" designation (Nacht) for clarity on D-3 and 5s . Others added the roman numeral VII to the D-7s, perhaps to reflect that the aircraft was fitted with the [[Luftwaffe radio equipment of World War II|FuG 7]] radio. A great deal of confusion exists concerning the D-7. Its existence has been questioned, but the type is listed in Junkers company records and in the ''Der Reichsminister der Luftfahrt'' and ''Oberbefehlshaber der Luftwaffe Technisches Amt''.  There was no production "nacht stuka", and modifications could vary according to the sub-contractor and depending on what parts were available.<ref name="Smith 2011 352–353">{{harvnb|Smith|2011|pp=352–353}}</ref>

A Stuka repair centre was set up at Wels-Lichtenegg. From May 1940 to November 1944, 746 were repaired and flight-tested there. In the winter 1943/44, the ''Metal Works Lower Saxony Brinckmann und Mergell'' company (Menibum) converted approximately 300 Ju 87D-3 and 5s to night versions. Dive-brakes were removed there, while gun muzzles and dampers were installed to eliminate exhaust and muzzle flash. The [[Jumo 211]]P engine was installed in some cases. It took 2,170 technicians and workers to carry out the conversions. Total figures for conversions to night flying operations are unknown. The company's equipment was seized by the [[Soviet Union]] at the end of the war, and the records were lost or destroyed.<ref name="Smith 2011 352–353"/> A main piece of equipment, hereto not installed in the Ju 87, was the FuG 101 Electronic Radio Altimeter. This was used to measure height. Some Ju 87s also used FuG 16Z transmitter/receiver set to augment the FuG 25 IFF (Identification Friend or Foe).<ref name="Smith 2011 352–353"/>

Pilots were also asked to complete the new "Blind Flying Certificate 3", which was especially introduced for this new type of operation. Pilots were trained at night, over unfamiliar terrain, and forced to rely on their instruments for direction. The Ju 87's standard Revi C12D gunsight was replaced with the new ''Nachtrevi'' ("Night revi") C12N. On some Ju 87s, the Revi 16D was exchanged for the Nachtrevi 16D. To help the pilot see his instrument panel, a violet light was installed.<ref>{{harvnb|Griehl|2001|p=210}}</ref>

On 15 November 1942, the Auxiliary ''Staffel'' was created. By mid-1943, [[Luftflotte 1|''Luftflotte'' 1]] was given four ''Staffeln'' while [[Luftflotte 4|''Luftflotte'' 4]] and ''Luftwaffe Kommando Ost'' (Luftwaffe Command East) were given six and two respectively. In the first half of 1943, 12 ''Nachtschlachtgruppen'' ("night battle groups"—NSGr) had been formed, flying a multitude of different types of aircraft, including the Ju 87, which proved itself ideally suited to the low-level slow flying needed.<ref>{{harvnb|Griehl|2001|pp=210–212}}</ref> NSGr 1 and 2 fought with some success on the [[Western Front (World War II)|Western Front]] during the [[Battle of Normandy]] and [[Battle of the Bulge]].<ref>{{harvnb|Parker|1998|p=208}}</ref><ref>{{harvnb|Ward|2004|p=200}}</ref> NSGr 7 operated in "anti-partisan" role from bases in [[Albania]] from July 1944, replacing their use of German trainers.<ref>{{harvnb|Smith|2011|p=354}}</ref> The 3rd and 4th group served on the Eastern Front, the 8th in the [[Arctic]] and the 9th in Italy.<ref>{{harvnb|Smith|2011|pp=356, 363}}</ref> NSGr 20 fought against the [[Western Allied invasion of Germany]] in 1945. Photographic evidence exists of 16 NSGr 20 Ju 87s lining up to take-off in the woods circling the Lippe airfield, Germany while under attack from [[Republic P-47 Thunderbolt]]s of the USAAF [[IX Tactical Air Command]]. The unit operated against the [[Ludendorff Bridge]] during the [[Battle of Remagen]].<ref>{{harvnb|Smith|2011|p=364}}</ref>