Medium Bombers Chapter III

The Early War Years


It has become traditional to see the death of Lieutenant-General Walther Wever, in an air accident in June 1936, as a turning point in the history of the Luftwaffe. Wever, so holds the story, was the main proponent of heavy long-range bombers in the Luftwaffe, and the decision after his death (actually some time later, in April 1937) to abandon these aircraft in favour of smaller bombers and dive bombers was a fatal strategic mistake that doomed Germany to defeat. But that version of events probably reflects the prejudices of Allied strategists more than the reality of the German position. For a start, it is wrong to infer from the cancellation of the Dornier Do 19 and Junkers Ju 89 that the Luftwaffe entirely abandoned the idea of acquiring long-range bombers, as a few weeks later, Heinkel received a contract for what would become the He 177. That was to be an unlucky aircraft, but its specification in significant ways paralleled the British specification P.13/36, which would lead to the Lancaster and Halifax.

It is true that Wever gave his support to the development of two large four-engined bombers, built to a specification issued in the summer of 1935. But it is important to consider that these prototypes were not all that impressive. The program is often referred to as the “Ural Bomber” program, an evocative name that suggests the ability to cover the entirety of Europe and brings to mind the evacuation of Soviet industrial plants to the Ural Mountains and beyond in 1941. (A need accurately envisaged by Wever.) But the Ural is about 3000 km east of Berlin. The Dornier Do 19 and Junkers Ju 89 had a maximum range of 2000 km, not even enough for a round-trip to the Ural Mountains starting from Moscow! With the intended bomb load of 1600 kg (modest enough, by heavy bomber standards) range was cut to 1600 km. From bases in Germany, that wasn’t even enough to fully cover Britain or France. Even before these types made their first flights, the air force realised that it needed more, and drafted a new “Bomber A” specification with a maximum range of 5000 km.

When they made their first flights in 1936 and 1937, the Do 19 and Ju 89 were both obsolescent technology, not unlike the American XB-15. Both aircraft were underpowered, the Ju 89 by four DB600 in-line inverted V-12 engines, the Do 19 by four 9-cylinder radials, in the first prototype the 715 hp Bramo 322H-2, but intended to be replaced by the BMW 132F. The unarmed Ju 89V1 had a top speed of 389 km/h, the projected speed of a putative Do 19A production aircraft with lighter defensive armament was 370 km/h. Both had been designed to have 20-mm MG-FF cannon in hydraulically powered dorsal and ventral turrets, an advanced feature that turned out to be impracticably heavy, especially as these turret designs required two men to operate them (presumably a gunner and a loader, as the MG FF was fed with drums). The Luftwaffe rightly considered that these types might be useful as transport aircraft (the Ju 89 did have an impressive potential to carry large and heavy loads) but were unfit for combat. Continued development of the Ju 89 would, by 1942, result in the very useful Ju 290 long-range reconnaissance aircraft. But this process involved a step-wise replacement of the fuselage, engines, wing, and landing gear, so that the Ju 290 did not have much in common with the Ju 89.

American and British critics of Luftwaffe policy with hindsight saw the decision to cancel the “Ural bomber” as a shift towards a tactical role for the Luftwaffe, and away from a strategic role. RAF and USAAF theorists saw the strategic role as the proper role for an independent air force, the role in which it could make its own independent contribution to victory. But unlike the Germans, they did not have a direct land border with the enemy to worry about. The Luftwaffe could hardly avoid given direct and indirect support to the Army, certainly not after combat experience in Spain had demonstrated the value of this.

From the perspective of the RLM, Germany’s rapidly expanding aircraft industry had enough difficulty producing a sufficient number of smaller aircraft, and the production of a small number of heavy bombers of dubious operational usefulness was not desirable. Machine tools, raw materials and fuel were already scarce. It seems implausible that the Do 19 or Ju 89, if they had been put in production, would have been very effective in the battle of Britain. They could carry more bombs farther than the medium bombers, but the available escort fighters were short ranged. The greater likelihood is that they would have suffered heavy losses if they had ventured beyond escort range, or would have been used for inaccurate night bombing raids only. The decision to focus on the mass production of the available medium bomber designs in 1937 was probably the technically correct one, as several modern designs with good performance were available.

The least successful of these designs was the Junkers Ju 86. This type had made its first flight in January 1935, but bomber production was ended in 1938 and the type was phased out from combat duties. The Ju 86 had been designed to have dual civilian and military roles, as outlined in a specification issued in 1933. Unlike its contemporaries, it was large enough to be a useful airliner in civil guise, carrying ten passengers in reasonable comfort, and even enjoyed modest export success as such. The bomber version had defensive gunnery positions in the nose, and open dorsal position, and a ventral “dustbin” turret. It could carry 1000 kg of bombs internally. In combat in Spain the innovative Jumo 205D Diesel engines of the Ju 86D proved a liability, as they were unreliable and responded poorly to the stresses of combat use. The Ju 86E adopted the BMW 132F radial, and Sweden built the type as the B3 bomber with Bristol Mercury engines. But even the Ju 86E was clearly outperformed by later types, and the last would be retired from bomber units after the brief campaign in Poland. The Ju 86 survived in Luftwaffe service in a handful of specialised high-altitude versions with Jumo 207 engines, increased wing span, and pressurised cabins, the Ju 86P of 1940 and the Ju 86R of 1943.

The direct competitor of the Ju 86 was the Heinkel He 111 and this design would have a long career, by some standards an excessively long one. As it made its first flight in February 1935, the He 111V1 prototype was a beautiful aircraft, with elliptical wings and tail surfaces and a streamlined fuselage. It was unpractical and uneconomical as a commercial transport and would be operated only in limited numbers by DHL. The initial He 111A-0 bomber as evaluated in 1936 was also unsuitable as a bomber, because with BLW VI 6,0Z liquid-cooled engines it was decidedly underpowered and sluggish when fully loaded. However, the BMW VI was regarded as little more than an interim engine, and a version powered by the new Daimler-Benz DB600 engine was already being tested. This He 111B entered service in late 1936. It was armed with the traditional three rifle-calibre machine guns (7.9mm MG15) in nose, dorsal, and ventral positions. It carried its bombs in vertical cells in the internal bay between the wings, from which they were released with a characteristic rotating drop, familiar from wartime footage as this feature was retained by all later He 111s. The He 111B-2 was the first major production version, with 950 hp DB 600CG engines. But the Daimler-Benz inverted V-12 was much in demand for fighter applications. Consequently, the Luftwaffe did not accept the He 111D with 1050 hp DB600Ga engines in a much improved, more streamlined installation. Instead, from January 1938 production switched the He 111E with 1075 hp Jumo 211A-1 engines. Although technologically advanced, the Jumo 211 would always be a “bomber engine” while the DB600 and DB601 were prioritised for fighter applications.

The He 111B was very quickly sent to fight in the Spanish Civil War, where the Ju 52/3m had clearly shown its limitations as a bomber, followed by the He 111E as soon as these became available. In various deliveries a total of 95 Heinkels would be sent, of which 58 survived the war and were handed over to the new Spanish air force. They quickly proved to be the best of the German bombers in Spain, being superior to the Do 17 and Ju 86 and far superior to the Ju 52/3m. The He 111 had a good performance, had fine handling characteristics and carried a decent bomb load. Despite its speed it was vulnerable to interception by modern fighters, in particular the I-16, but combat losses were still relatively light.

Meanwhile, the wing of the He 111 had been redesigned to simplify production, abandoning the elliptical contours in favour of straight leading and trailing edges, with rounded wing tips. This resulted in the production of the He 111F, with Jumo 211 engines, and the He 111J, its equivalent with DB 600 engines, as the supply situation of the latter had improved. The F and J were to prove interim models as another major redesign was in the works, in the form of a new, fully glazed, and somewhat asymmetrical, nose. The pilot moved from a traditional stepped cockpit to the left seat position in the nose, with the gunner and bomb aimer to his right. This the gun mount in the tip of the nose was offset to the right. The ventral “dustbin” turret was replaced by a permanent ventral fairing, and the dorsal gunnery position was redesigned, but the same three 7.9 mm machine guns still constituted its defensive armament. In this form, the He 111 now looked as it is most familiar from WWII pictures. With 1175 hp DB 601Aa engines this He 111P-1 had a maximum speed of 400 km/h, though this decreased to 325km/h with a maximum load. It could carry 2000 kg of bombs.

The new cockpit design fell in with the trend of Luftwaffe bombers. Bulbous cockpits with extensive glazing, usually a large number of small panels, and often without a “step” for the pilot’s windscreen, appeared not only on the He 111 but also on the Do 17, Ju 88, Ju 188, He 177, and even the reconnaissance models of the Ju 86. They put several crew members in close proximity in the nose of the aircraft and provided a good all-around view. This strongly contrasted with the RAF design philosophy of designing bombers with a nose gun turret, which necessarily put the cockpit farther back. The German preference thus emphasised ergonomics over defensive firepower.

Initially, the Luftwaffe initiated parallel production of the He 111P with DB 601 engines and the He 111H with Jumo 211 engines. First the He 111P entered service in the spring of 1939, with the He 111H following a little later. The production rate was quite high, as three factories were building the He 111P and three more the He 111H, with the latter being built at a rate of about 100 per month! Older He 111 models were quickly replaced and the Luftwaffe entered the war with 389 P-series aircraft and 400 H-series, as well as a small number of older models to make a total of 808 He 111 bombers. From early on in 1940 only the He 111H would be built, as there was a more plentiful supply of the Jumo 211, and standardisation had its advantages.

But despite the substantial design modernisation that the He 111H and P series represented, the He 111 was fundamentally an older bomber design. Its performance was no longer fully adequate and its defensive armament was weak. The He 111P-4 and H-2 had an additional gun in the nose plus two more firing through side windows, with an increase of the crew from three to five, but this was still an inadequate defence. The H-3 introduced an MG FF cannon in the front of the ventral gondola. The opposition encounter over Poland and France was largely ineffective, but the losses encountered over Britain were high. The He 111 was in fact being gradually phased out in favour of the faster, superior Ju 88, for which the Reich had adopted mass production methods, while the Luftwaffe also looked forward to receiving the Ju 288 and He 177. If production had been 1399 aircraft in 1939, it decreased to 827 in 1940 and 930 in 1941. By August 1941, attrition had reduced the total frontline strength to 190.

But the He 111 nevertheless remained in production until late 1944, well beyond the initial plan of phasing out production in early 1942. Instead production increased again to 1337 in 1942 and 1408 in 1943. It was fundamentally a good aircraft with excellent flying characteristics, it was easy to produce and maintain, and it was well-liked and versatile. The He 111H-6 with Jumo 211F-1 engines and broad-bladed propellers became a major production model, as was the H-16 with Jumo 211F-2 engines and various improvements. Defensive armament was somewhat reinforced by moving the MG FF into the fuselage nose, and replacing the MG15 with the newer MG81 or the 13mm MG131. Some late production aircraft had a small electrically powered dorsal turret with a single MG131. But the He 111 was increasingly seen in supporting roles: As a transport, as a carrier for guided missiles or an air-launched V-1, as a paratroop aircraft, a glider tug, or a sweeper of magnetic mines. A proliferation of subtypes had various defensive armament improvements or special mission equipment. If nothing else, the He 111H proved adaptable. Because the Jumo 211 was being phased out of production, the He 111H-21 of early 1944 was fitted with the 1750hp Jumo 213E-1, and the final version was the He 111H-23 with Jumo 213A-1 engines. The 714 aircraft built in 1944 ended a production run of over 7000 He 111s, the majority of which had been built after the type became obsolescent.

Dornier Do 17

Junkers Ju 88