The design and evolution of one of Germany’s most versatile World War Two bombers is examined by Chris Goss
Initially envisaged as a dive bomber with a crew of three, the Junkers Ju 88 became operational in September 1939 and was first seen over Great Britain on October 16, 1939. It then served throughout the war in all theatres in many different roles, including night-fighter, long-range intruder, tank-buster, reconnaissance and torpedo bomber. It is consequently an excellent example of a multi-role combat aircraft, with its basic airframe successfully modified for many different mission types.
Development and into battle
In 1934, a specification was issued by the Reichsluftfahrtministerium (RLM) for a heavily-armed, multipurpose aircraft capable of being used as a bomber, heavy fighter, close support and reconnaissance aircraft. However, in 1935, this proposal was modified – now a ‘schnellbomber’ (high-speed bomber) was sought. This resulted in a specification calling for an aircraft that was defensively armed, had a maximum bombload of 1,760lbs, a maximum speed of 310mph, the ability to climb (with load) to 23,000ft in 25 minutes and a short take-off and landing capability. The proposal was issued to Focke-Wulf, Henschel, Messerschmitt and Junkers, but it was the last of these – Junkers Flugzeug-und Motorenwerke AG – that wanted to use the latest structural techniques.
Working to a tight deadline at its Dessau factory, Junkers began the project in mid-January 1936. It was focusing on two designs: a twin tailfin aircraft known as the Ju 85 and a single fin variant known as the Ju 88. It was the latter that was selected by the RLM in May 1936, after which work began on three prototypes, the first of which was completed and flown on December 21, 1936.
The initial prototype was powered by two Daimler-Benz DB600Aa engines, as was prototype V2, which had modified radiator intakes. The V3, which first flew in September 1937, was powered by Junkers Jumo 211A engines, had a raised cabin roof, an additional rear-firing machine gun and an offset gondola housing a bomb sight. This aircraft performed so well that contracts were placed in early 1938.
However, as was common at the time, the RLM had already made changes to the initial requirement. They now wanted the Ju 88 to be a dive-bomber with increased defensive armament. This resulted in V4, which looked more like the eventual Ju 88 with its distinctive glazed nose. The V5 version then reverted to having no gondola, a solid nose cone and Jumo 211B engines. But it was V6, which first flew in June 1938, that turned out to be the first production prototype. Subtle modifications followed with the fitting of dive brakes and bomb racks and, after the V10, the first production Ju 88A-1s began to leave the assembly line in March 1939. Even with completed aircraft rolling out of the factory, development continued – there were another five prototypes after the V10.
The first Ju 88s were assigned to Erprobungskommando 88 in spring 1939 – this became I Gruppe/Kampfgeschwader 25 (I./ KG 25) in August of that year and, soon after, I./KG 30. This Gruppe was commanded by experienced pilot and engineer Hptm Helmut Pohle. Twelve aircraft of I./KG 25 based at Jever in northern Germany were declared part of Luftflottenkommando 2 at the outbreak of war, but it was I/.KG 30 which would be the first to fly an operational mission, over the North Sea on September 26, 1939.
It lost its first Ju 88A-1, flown by Oblt Konrad Kahl, during an attack on British warships on October 9, 1939. Hit by flak, the aircraft came down in the sea – Kahl and one other of the crew of four were rescued. Seven days later, the Ju 88 became better known to the British when two were shot down by RAF fighters while attacking warships in the Firth of Forth. These aircraft were flown by Helmut Pohle and the 1 Staffelkapitän Oblt Sigmund Storp, both of whom were captured. Command of I./KG 30 was now taken on by Maj Fritz Doensch. By the end of 1939, II./KG 30 under Hptm Claus Hinkelbein, had been formed, with III./KG 30, commanded by Hptm Siegfried Mahrenholtz, forming in January 1940. The Geschwader as a whole was led by Obstlt Walter Loebel. By April 8, 1940, KG 30 was able to operate as a full Geschwader in Norway during both the campaign over that nation and later in the Battle of France.
In the spring and early summer of 1940, a number of Heinkel He 111 units, including KG 51 and KG 54, and Dornier Do 17 units such as KG 77, began converting to the newer and faster bomber as more Ju 88s became available. By August 13, 1940, Ju 88 bomber units comprised III./KG 4, KG 30, KG 51, KG 54, II./KG 76 and Kampfgruppe 806, with KG 77 undergoing conversion training until September 1940. At the same time, a number of Do 17 reconnaissance units were also converting to the Ju 88.
Time for change
Despite some early successes, the rapid pace of the war made it clear that performance deficiencies in the A-1 would require some major upgrades. The outcome was the Ju 88A-4, which had improved engines, was longer (65ft 10in) and had improved wings and a strengthened undercarriage. At the same time, A-1s were now modified to A-4 specification and became the Ju 88A-5, many units being equipped with this variant before the arrival of the bespoke A-4. Production of the A-4 was being hampered by a lack of Jumo 211J engines.
Junkers Ju 88A-1s were also having single 20mm MG FF cannon and three 7.92mm MG 17 machine guns fixed into a solid nose – those modified in this way were renamed Ju 88C-1 and C-2. The first unit to receive these new aircraft was Oblt Herbert Boensch’s Zerstörerstaffel KG 30, which saw action in Norway in April to June 1940, before returning to Germany and being re-designated II./ Nachtjagdgeschwader 1 (II./NJG 1), a night-fighter unit, in July 1940. This unit soon became I./NJG 2 and was used on intruder missions over Britain until October 1941.
The Ju 88C-2 would evolve into the Ju 88C-4 – featuring different engines, with bomb equipment removed and new propellers added – and ultimately the Ju 88C- 6, which was purpose-built as a night-fighter. Despite this new, nocturnal guise, it was frequently used in daylight as a heavy fighter over Russia, the Mediterranean and, most notably, the Bay of Biscay with the unit V./KG 40. Meanwhile, the Ju 88A-4s and A-5s continued to perform bomber and reconnaissance tasks wherever Germany was in action.
“The proposal was issued to Focke-Wulf, Henschel, Messerschmitt and Junkers, but it was the last of these that wanted to use the latest structural techniques”
Given the pace of change, it was inevitable that there would be further developments and modifications to the type. Based on the A-5, the Ju 88A-6 was a bomber fitted with a balloon cutter (kutonase). The A-7 was a dual-control trainer, the A-8 was another balloon cutter based on the A-4, the A-9 was a tropicalised A-1 for operations in the desert and the A-10 was a tropicalised A-5. The A-11 had an increased bombload and a modified weapons bay, the A-12 was a trainer based on the A-4 and the A-13 was modified from the A-1 specifically for ground attack, with increased armour plating, bomb capacity and new gun pods.
The A-14 was based on the A-4 and fitted with larger wings and balloon cutters – it also had an increased range of 1,560 miles, increased ordnance capacity and an operating altitude of 26,500ft. An even bigger bomb load could be carried by the A-15, while the A-16 was a trainer based on the A-14. Finally, the A-17 was a torpedo bomber based on the A-4. Each variant was still powered by the Jumo 211, but these were usually improved sub-variants of the original powerplant.
Junkers also began to refine and improve on the basic Ju 88A versions. The Ju 88D-1 to D-5 were purpose-built for reconnaissance missions, powered initially by the Jumo 211 and then, with the D-6, by BMW 801 engines. The Ju 88H was designed for long range reconnaissance and bombing missions – the H-1 to H-3 were powered by BMW 801 engines, while the H-4 was fitted with Jumo 213s.
The Ju 88 P-1 to P-4 was a range of heavily-armed and armoured tank destroyers powered by Jumo 211 engines, with each sub-variant having different armament. The Ju 88S (with four subvariants) was a high-speed, more aerodynamically refined bomber and, finally, the Ju 88T was a highspeed reconnaissance aircraft, with the T-1 powered by BMW 801s and the T-3 by Jumo 213s.
Ultimate night-fighter
There would also be two purpose built variants of the Ju 88 night fighter, which were intended to replace the Ju 88C-6. The Ju 88R was both a night-fighter and heavy day-fighter – it was essentially a Ju 88C-6 fitted with BMW 801A engines, designed to have more power and speed than the C-6, although the armament remained the same. The RAF managed to obtain a pristine example of a Ju 88R-1 when a crew from 10./NJG 3 defected and landed a nearly new aircraft in Scotland on May 9, 1943.
Although intended for night missions, the aircraft were frequently operated in daylight, especially by V./KG 40 (which, in October 1943, became I./ Zerstörergeschwader 1) over the Bay of Biscay and the Mediterranean. This unit used the R-2 variant, which was powered by BMW 801D engines, as opposed to the BMW 801A fitted to its predecessor. Use of the new powerplants also necessitated some modifications to the engine cowlings. The armament was unchanged, but the R-2 had increased armour, including a strengthened windscreen. The unit lost its first of these aircraft in an accident on January 29, 1944.
The ultimate Ju 88 night-fighter, however, was the Ju 88G, a variant specifically designed and built to operate after dark. This version was not only cleaner looking, but it was faster and more heavily armed, utilising the Ju 188 fuselage and tail plane. The Ju 88G-1 was powered by two BMW 801G engines and thus looked similar to the Ju 88R-1, apart from the improved, more angular tail. In addition to increased protective armour, it was equipped with six belt-fed 20mm MG151 cannon – two in the nose and four in an offset belly pack – and an MG 131 for rearward defensive fire. It could also be fitted with the Schräge Musik obliquely-mounted cannon behind the cockpit, and was equipped to carry bombs. The RAF again managed to obtain an example when a Ju 88G-1 from 7./ NJG 2 landed in error at an airfield in East Anglia on July 13, 1944.
This specialised variant began leaving the production line in late 1943, followed in mid-1944 by the Ju 88G-6, which was powered by Jumo 213E engines. This would be succeeded by the final production model, the Ju 88G-7, which was powered by Jumo 213E-1 engines and had extended wings derived from the Ju 188. However, the first G-7 was not allocated until the end of March 1945, too late to make any impact in the air war. All the night-fighters were equipped with various types of airborne radar, either the FuG 202, 212 or 220 Lichtenstein, FuG 227 Flensburg, FuG 350 Naxos, FuG 218 Neptun or FuG 240 Berlin.
Twilight
With the tide of war turning against Germany, another unusual and perhaps rather desperate use for the Ju 88 was considered. Preparing the so-called ‘Mistel’ flights, mechanics set about placing a Messerschmitt Bf 109 single-seat fighter on top of a Ju 88 – the latter was unmanned and controlled by the pilot in the cockpit of the uppermost aircraft. In this remarkable configuration, the Junkers was effectively operating as an unmanned drone, with its nose filled with explosives that would be released near its target, allowing the smaller aircraft to return to base.
“The rapid pace of the war made it clear that performance deficiencies in the A-1 would require some major upgrades”
At the same time, static tests were being carried out against captured French warships, with a hollow-charged warhead. When detonated, the munition drove through the vessels’ armour, which had been strengthened to make the tests more thorough. In another trial, a warhead successfully blasted through a 59ft wall of concrete. Impressed by the results, Junkers began to devise a process whereby a similar warhead could be fitted to a Ju 88 by specialist armourers in the field. Controlled by the Bf 109 pilot, the Mistel Ju 88 would be a formidable weapon and they were used operationally from mid-1944, sometimes with a Fw 190 on top, but with limited success and in very small numbers.
In various different forms, the Ju 88 was still in frontline service at the end of the war – and not just with the Luftwaffe, but also in Finland, Hungary, Romania and Italy. It was even used by the French Air Force after the war.
More than 15,000 Ju 88s were produced and several aircraft – or their remains – can be found in museums and private collections around the world. Complete and partial survivors currently comprise two A-1s, three A-4s, three A-5s, two C-2s, three D-1s, an R-1 and a G-1. The most impressive examples can be found at Hendon’s RAF Museum and at the National Museum of the USAF in Dayton, Ohio – both of these were flown by defecting aircrew. The UK attraction has Ju 88R-1 Wk Nr 360043 coded D5+EV of 10/NJG 3 – this was the machine surrendered at RAF Dyce in Scotland in 1943. The US example is Ju 88D-1/Trop Wk Nr 430658, originally NP+MK but now coded White 1 of the Romanian Air Force’s Escadrilla 2 – it was flown by a lone crew member to RAF Akrotiri in Cyprus on July 22, 1943. FP
“In various forms, the Ju 88 was still in frontline service at the end of the war”
