The Heinkel 111 series was one of the many ‘undercover’ pre-war German aircraft designed by Siegfried and Walter Günter at Heinkel Flugzeugwerke in 1934. After its defeat in World War I, Germany was banned from operating an air force by the Treaty of Versailles. German re-armament began earnestly in the 1930s and was initially kept secret because it violated the treaty. The early development of military bombers was disguised as a development program for civilian transport aircraft. For this reason, throughout development it was described as a "wolf in sheep's clothing” because the project masqueraded the machine as civilian transport, though from conception the Heinkel was intended to provide the fledgling Luftwaffe with a fast medium bomber.
Perhaps the best-recognised German bomber due to the distinctive, extensively glazed "greenhouse" nose of later versions, the Heinkel He 111 was the most numerous Luftwaffe bomber during the early stages of World War II. The bomber fared well during the Spanish campaign as part of the Condor Legion.
While the first prototypes of the Heinkel 111B were found to be underpowered, as they were equipped with 578 hp, it was not until these were replaced at the start of the Spanish Cival War with the more powerful Daimler-Benz 600 engines that the variant settled into front line service with successive variations going on to be used in a variety of roles on every front in the European theatre. It was used as a strategic bomber during the Battle of Britain, a torpedo bomber in the Atlantic and Arctic, and a medium bomber and a transport aircraft on the Western, Eastern, Mediterranean, Middle Eastern, and North African Front theatres.
Only ten He 111 A-0 models based on the V3 were built, but they proved to be underpowered and were eventually sold to China. The type had been lengthened by 1.2 m (3.9 ft) due to the added 7.92 mm (.312 in) MG 15 machine gun in the nose. Another gun position was installed on top of the fuselage, and another in a ventral position as a "dustbin" exposed turret, which could retract. The bomb bay was divided into two compartments and could carry 680 kg (1,500 lb) of bombs. The problem with these additions was that the weight of the aircraft reached 8,200 kg. The He 111's performance was seriously reduced; in particular, the BMW VI 6.0 Z engines were not now powerful enough. The increased length also altered the 111's aerodynamic strengths and reduced its excellent handling on takeoffs and landings.
The crews found the aircraft difficult to fly, and its top speed was reduced significantly. Production was shut down after the pilots reports reached the Ministry of Aviation. However, a Chinese delegation was visiting Germany and they considered the He 111 A-0 fit for their needs and purchased seven machines.
The first He 111B made its maiden flight in the autumn of 1936, with the first production batch rolled off the production lines that summer, at Rostock. Seven B-0 pre-production aircraft were built, bearing the Werknummern (Works numbers) 1431 to 1437. The B-0s were powered by DB 600C engines fitted with variable pitch airscrews which increased the underpowered engines by a further 200 hp. The B-0 had a MG 15 machine gun installed in the nose and could also carry 1,500 kg bombs in their vertical cells.
The B-1 had some minor improvements, including the installation of a revolving gun-mount in the nose and a flexible Ikaria turret under the fuselage. Once these were added, the RLM ordered 300 He 111 B-1s; the first were delivered in January 1937. In the B-2 variant, engines were upgraded to the supercharged to almost 925 hp. The B-2 began to roll off the production lines at Oranienburg in 1937.
The He 111 B-3 also saw service as a modified trainer. However, the production orders were impossible to fulfill and only 28 B-1s were built. Owing to the production of the new He 111E, only a handful of He 111 B-3s were produced. Due to insufficient capacity, Dornier, Arado and Junkers built the He 111B series at their plants in Wismar, Brandenburg and Dessau, respectively. The B series compared favourably with the capacity of the A series. The bomb load increased to 1,500 kg while there was also an increase in maximum speed and altitude to 215 mph and a ceiling of 6,700 m
The design of the He 111 initially had a conventional stepped cockpit, with a pair of windscreen-like panels for the pilot and co-pilot. Subsequent production variants were fitted with fully glazed cockpits and a laterally asymmetric nose, with the port side having the greater curvature for the pilot, offsetting the bombardier to starboard. The resulting stepless cockpit, which was a feature on a number of German bomber designs during the war years in varying shapes and formats, no longer had the separate windscreen panels for the pilot. Pilots had to look outside through the same bullet-like glazing that was used by the bombardier and navigator.
The pilot was seated on the left and the navigator/bomb aimer on the right. The navigator went forward to the prone bomb-aiming position or could tilt his chair to one side, to move into the rear of the aircraft. In later models with teh introduction of the full ‘Greenhouse’ canopy, there was no cockpit floor below the pilot's feet—the rudder pedals being on arms—giving very good visibility below. Sliding and removable panels were manufactured into the nose glazing to allow the pilot, navigator and or bomb aimer to exit the aircraft quickly, without a time-consuming retreat into the fuselage.
For the German pilots, overall impression of space within the cockpit area and the great degree of visual sighting afforded by the Plexiglas panelling were regarded as positive factors, with one important provision in relation to weather conditions. Should either bright sunshine or rainstorms be encountered, the pilot's visibility could be dangerously compromised either by glare throwback or lack of good sighting.
Taxiing was easy and was only complicated by rain, when the pilot needed to slide back the window panel and look out to establish direction. On take off, pilots experienced very little "swing" and the aircraft appeared well balanced. On landing, pilots were advised to keep the approach speed above 145 km/h until touchdown. This was to avoid a tendency by the He 111 to drop a wing, especially on the port side.
The fuselage contained two major bulkheads, with the cockpit at the front of the first bulkhead. The nose was fitted with a rotating machine gun mount, offset to allow the pilot a better field of forward vision. The cockpit was fully glazed, with the exception of the lower right section, which acted as a platform for the bombardier-gunner. The commonly-used Lotfernrohr-series bombsight penetrated through the cockpit floor into a protective housing on the external side of the cockpit
Between the forward and rear bulkhead was the bomb bay, which was constructed with a double-frame to strengthen it for carrying the bomb load. The space between the bomb bay and rear bulkhead was used up by Funkgerät radio equipment and contained the dorsal and flexible casemate ventral gunner positions. The rear bulkhead contained a hatch which allowed access into the rest of the fuselage which was held together by a series of stringers. The wing was a two spar design. The fuselage was formed of stringers to which the fuselage skin was riveted. Internally the frames were fixed only to the stringers, which made for simpler construction at the cost of some rigidity.
The wing leading edges were swept back to a point inline with the engine nacelles, while the trailing edges were angled forward slightly. The wing contained two 700lt fuel tanks between the inner wing main spars, while at the head of the main spar the oil coolers were fitted. Between the outer spars, a second pair of reserve fuel tanks were located, carrying an individual capacity of 910lt of fuel. The outer trailing edges were formed by the ailerons and flaps, which were met by smooth wing tips which curved forward into the leading edge.
The control systems also featured numerous innovations. The control column was centrally placed and the pilot sat on the port side of the cockpit. The column had an extension arm fitted and had the ability to be swung over to the starboard side in case the pilot was incapacitated. The control instruments were located above the pilot's head in the ceiling, which allowed viewing and did not block the pilot's vision. The fuel instruments were electrical. The He 111 used the inner fuel tanks, closest to the wing root, first. The outer tanks acted as reserve tanks.
* Images shown are a guide and references only to show how the kit can be assembled allowing for modellers to add extra detail as required