The Heinkel He 111 was a German aircraft designed by Siegfried and Walter Günter in the early 1930s in violation of the Treaty of Versailles. Often described as a "wolf in sheep's clothing", it masqueraded as a transport aircraft, though its actual purpose was to provide the Luftwaffe with a fast medium bomber.
Perhaps the best-recognised German bomber due to the distinctive, extensively glazed, bullet-shaped "greenhouse" nose of later versions, the Heinkel was the most numerous and the primary Luftwaffe bomber during the early stages of World War II. It fared well until the Battle of Britain, when its weak defensive armament, relatively low speed, and poor manoeuvrability were exposed. Nevertheless, it proved capable of sustaining heavy damage and remaining airborne. As the war progressed, the He 111 was 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 during the Battle of the Atlantic, and a medium bomber and a transport aircraft on the Western, Eastern, Mediterranean, Middle Eastern, and North African Fronts.
Although constantly upgraded, the Heinkel He 111 became obsolete during the latter part of the war. It was intended to be replaced by the Luftwaffe's Bomber B project, but the delays and eventual cancellation of the project forced the Luftwaffe to continue using the He 111 until the end of the war. Manufacture ceased in 1944, at which point, piston-engine bomber production was largely halted in favour of fighter aircraft. With the German bomber force defunct, the He 111 was used for transport and logistics.
The design of the Heinkel endured after the war in the CASA 2.111. The Spanish received a batch of He 111H-16s in 1943 along with an agreement to licence-build Spanish versions. Its airframe was produced in Spain under license by Construcciones Aeronáuticas SA. The design differed significantly in powerplant only. The Heinkel's descendant continued in service until 1973.
Design and development
Heinkel He 111 in flight.
After its defeat in World War I, Germany was banned from operating an air force by the Treaty of Versailles. German re-armament began in the 1930s and was initially kept secret because it violated the Treaty. Therefore, the early development of military bombers was disguised as a development program for civilian transport aircraft.
In the early 1930s Ernst Heinkel decided to build the world's fastest passenger aircraft, a goal met with scepticism by Germany's aircraft industry and political leadership. Heinkel entrusted development to Siegfried and Walter Günter, both fairly new to the company and untested. In June 1933 Albert Kesselring visited Heinkel's offices. Kesselring was head of the Luftwaffe Administration Office: at that point Germany did not have a State Aviation Ministry but only an aviation commissariat, the Luftfahrtkommissariat. Kesselring was hoping to build a new air force out of the Flying Corps being constructed in the Reichswehr and convinced Heinkel to move his factory from Warnemünde to Rostock and turn it over to mass production with a force of 3,000 employees who would produce the first He 111. Heinkel began a new design for civil use in response to new American types that were appearing, the Lockheed 12, Boeing 247 and Douglas DC-2.
The first single-engined Heinkel He 70 Blitz ("Lightning") rolled off the line in 1932 and the type immediately started breaking records. In its normal four-passenger version its speed reached 380 km/h (230 mph), powered by a 447 kW (600 hp) BMW VI engine. The elliptical wing that the Günther brothers had already used in the Bäumer Sausewind sports plane before they joined Heinkel became a feature in this and many subsequent designs they developed. The design drew the interest of the Luftwaffe, which was looking for an aircraft with dual bomber/transport capabilities.
The He 111 was a twin-engine version of the Blitz, preserving the elliptical inverted gull wing, small rounded control surfaces and BMW engines, so that the new design was often called the Doppel-Blitz ("Double Blitz"). When the Dornier Do 17 displaced the He 70, Heinkel needed a twin-engine design to match its competitors. Heinkel spent 200,000 hours developing it. The fuselage length was extended to just over 17.4 m/57 ft (from 11.7 m/38 ft 4½ in) and wingspan to 22.6 m/74 ft (from 14.6 m/48 ft).
The first He 111 flew on 24 February 1935, piloted by chief test pilot Gerhard Nitschke, who was ordered not to land at the company's factory airfield at Rostock-Marienehe (today's Rostock-Schmarl neighbourhood), as this was considered too short, but at the central Erprobungstelle Rechlin test facility. He ignored these orders and landed back at Marienehe. He said that the He 111 performed slow manoeuvres well and that there was no danger of overshooting the runway. Nitschke also praised its high speed "for the period" and "very good-natured flight and landing characteristics", stable during cruising, gradual descent and single-engined flight and having no nose-drop when the undercarriage was operated. However during the second test flight Nitschke revealed there was insufficient longitudinal stability during climb and flight at full power and the aileron controls required an unsatisfactory amount of force.
By the end of 1935, prototypes V2 V4 had been produced under civilian registrations D-ALIX, D-ALES and D-AHAO. D-ALES became the first prototype of the He 111 A-1 on 10 January 1936, and received recognition as the "fastest passenger aircraft in the world", as its speed exceeded 402 km/h (250 mph). The design would have achieved a greater total speed had the DB 600 engines of 746 kW (1,000 hp) been added. However, German aviation industries lacked power plants with more than 447 kW (600 hp). Heinkel were forced to use the BMW VI glycol-cooled engine.
During the war, test pilot Eric Brown evaluated many Luftwaffe aircraft. Among them was a He 111 H-1 of Kampfgeschwader 26 which was forced to land at the Firth of Forth on 9 February 1940. Brown described his impression of the He 111s unique greenhouse nose:
The 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, Brown reported very little "swing" and the aircraft was well balanced. On landing, Brown noted that approach speed should be above 145 km/h (90 mph) and should be held until touch down. This was to avoid a tendency by the He 111 to drop a wing, especially on the port side.
In the mid-1930s, Dornier Flugzeugwerke and Junkers competed with Heinkel for Ministry of Aviation contracts. The main competitor to the Heinkel was the Junkers Ju 86. In 1935, comparison trials were undertaken with the He 111. At this point, the Heinkel was equipped with two BMW VI engines while Ju 86A was equipped with two Jumo 205Cs, both of which had 492 kW (660 hp). The He 111 had a slightly heavier takeoff weight of 8,220 kg (18,120 lb) compared to the Ju 86's 8,000 kg (17,640 lb) and the maximum speed of both aircraft was 311 km/h (193 mph). However the Ju 86 had a higher cruising speed of 177 mph (285 km/h), 9 mph (14 km/h) faster than the He 111. This stalemate was altered drastically by the appearance of the DB 600C, which increased the He 111's power by 164 kW (220 hp). The Ministry of Aviation awarded both contracts, and Junkers sped up development and production at a breathtaking pace, but the financial expenditure for the Junkers was huge. In 1934-1935, 3,800,000 RM (4½% of annual turnover) was spent. The Ju 86 appeared at many flight displays all over the world which helped sales to the Ministry of Aviation and abroad. Dornier, which was also competing with their Do 17, and Heinkel were not as successful. However, in production terms, the He 111 dominated with 8,000 examples produced. Just 846 Ju 86s were produced, and the Ju 86's weak performance could not match that of the He 111. Having dropped out of the race, Junkers concentrated on their Ju 88 design. It would be the He 111 that entered the Luftwaffe as the numerically dominant type at the beginning of the Second World War.
In view of this disaster [failure of the Ju 86], it was understandable that the Luftwaffe encouraged with particular urgency and attention conversion of the He 111 into a standard bomber. This was pursued in a similar manner to the Ju 86. Three machine-gun stands were installed that, spacewise, were more favourable, especially when the entire fuselage nose, including the cockpit, was later expanded to make provision for an all-round-vision canopy. Nobody sang praises to my fast commercial aircraft, something that eventually happened.
"The sheep": early civilian variants
The first prototype, He 111 V1 (W.Nr. 713, D-ADAP), first flew from Rostock-Marienehe on 24 February 1935. It was followed by the civilian-equipped V2 and V4 in May 1935. The V2 (W.Nr. 715, D-ALIX) used the bomb bay as a four-seat "smoking compartment", with another six seats behind it in the rear fuselage. V2 entered service with Deutsche Luft Hansa in 1936, along with six other newly built versions known as the He 111C. The He 111 V4 was unveiled to the foreign press on 10 January 1936. Nazi propaganda inflated the performance of the He 111C, announcing its maximum speed as 400 km/h (249 mph), in reality its performance standing at 360 km/h (224 mph). The He 111 C-0 was a commercial version and took the form of the V4 prototype design. The first machine, designated D-AHAO "Dresden". It was powered by the BMW VI engine and could manage a range (depending on the fuel capacity) of 1,000 km (621 mi) to 2,200 km (1,367 mi) and a maximum speed of 310 km/h (193 mph). The wing span on the C series was 22.6 m (74 ft 1¾in). The fuselage dimensions stood at 17.1 m (56 ft 1¾in) in the He 111 V1, but changed in the C to 17.5 m (57 ft 5 in). The Jumo 205 diesel-type powerplant engine replaced the BMW VI. Nevertheless, the maximum speed remained in the 220–240 km/h (137–149 mph) bracket. This was increased slightly when the BMW 132 engines were introduced.
A general problem existed in powerplants. The He 111 was equipped with BMW VI glycol-cooled engines. The German aviation industry lacked powerplants that could produce more than 600 hp. Engines of suitable quality were kept for military use, frustrating German airline Luft Hansa and forcing it to rely on the BMW VI or 132s.
He 111G - see Wikipedia
From the nose gunner's view
He 111 A - D - see Wikipedia
He 111 E - see Wikipedia
He 111 F - see Wikipedia
He 111 J - see Wikipedia
He 111 P - see Wikipedia
He 111H, the main variant
A Heinkel He 111H bomber, which was abandoned by the Luftwaffe during the retreat after the Battle of El Alamein.
He 111 H-1 to H-10
The H variant of the He 111 series was more widely produced and saw more action during World War II than any other Heinkel variant. Owing to the uncertainty surrounding the delivery and availability of the DB 601 engines, Heinkel began tests with the 820 kW (1,100 hp) Junkers Jumo 211 powerplants. The somewhat larger size and greater weight of the Jumo 211 engines were unimportant considerations for a twin engine design, and the Jumo was used on almost all early-war bomber designs. When the Jumo was fitted to the P model it became the He 111 H.
He 111H on a torpedo
training exercise, 10 October 1941
The He 111 H-1 was fitted with a standard set of three 7.92 mm (.312 in) MG 15s and eight SC 250 250 kg (550 lb) or 32 SC 50 50 kg (110 lb) bombs. The same armament was used in the H-2 which started production in August 1939. The P-series was gradually replaced on the eve of war with the new the H-2, powered by improved Jumo 211 A-3 engines of 820 kW (1,100 hp). A count on 2 September 1939 revealed that the Luftwaffe had a total of 787 He 111s in service, with 705 combat ready, including 400 H-1 and H-2s that had been produced in a mere four months. Production of the H-3, powered by the 895 kW (1,200 hp) Jumo 211 D-1, began in October 1939. The experiences during the Polish Campaign led to an increase in defensive armament. MG 17s were fitted whenever possible and the number of machine guns was increased to seven. Normally one MG 17 would be installed in the nose, one in the ventral position, dorsal position and one in each waist window position. The two waist positions received an additional MG 15 or 17. On some Heinkels a permanent belt-fed MG 17 was installed in the tail.
After the Battle of Britain, smaller scale production of the H-4s began. The H-4 was virtually identical to the He 111 P-4 with the DB 600s swapped for the Jumo 211D-1s. This variant also differed from the H-3 in that it could either carry 2,000 kg (4,410 lb) of bombs internally or mount one or two external racks to carry one 1,800 kg (3,970 lb) or two 1,000 kg (2,210 lb) bombs. As these external racks blocked the internal bomb bay doors, a combination of internal and external storage was not possible. A PVR 1006L bomb rack was fitted externally and an 835 L (221 US gal) tank added. The PVR 1006L was capable of carrying a SC 1000 1,000 kg (2,210 lb) bomb. Some H-4s had their PVC racks modified to drop torpedoes. Later modifications enabled the PVC 1006 to carry a 2,500 kg (5,510 lb) "Max" bomb. But 1,000 kg (2,200 lb) "Hermann" or 1,800 kg (3,970 lb) "Satans" were used more widely.
The H-5 series followed in February 1941, with heavier defensive armament. Like the H-4, it retained a PVC 1006 L bomb rack to enable it to carry heavy bombs under the fuselage. The first ten He 111 H-5s were pathfinders, and selected for special missions. The aircraft sometimes carried 25 kg flashlight bombs which acted as flares. The H-5 could also carry heavy fire bombs, either heavy containers or smaller incendiary devices attached to parachutes. The H-5 also carried LM A and LM B aerial mines for anti-shipping operations. After the 80th production aircraft, the PVC 1006 L bomb rack was removed and replaced with a heavy-duty ETC 2000 rack, enabling the H-5 to carry the SC 2500 "Max" bomb, on the external ETC 2000 rack, which enabled it to support the 5,000 lb (2,300 kg) bomb.
Some H-3 and H-4s were equipped with barrage balloon cable-cutting equipment in the shape of cutter installations forward of the engines and cockpit. They were designated H-8, but later named H8/R2. These aircraft were difficult to fly and the production stopped. The H-6 initiated some overall improvements in design. The Jumo 211 F-1 engine of 1,007 kW (1,350 hp) increased its speed while the defensive armament was upgraded with one 20 mm MG FF cannon in the nose position, one MG 15 in the ventral turret, and in each of the fuselage side windows (optional). Some H-6 variants carried tail-mounted MG 17 defensive armament. The performance of the H-6 was much improved. The climb rate was higher and the machine could reach a slightly higher ceiling of 8,500 m (27,200 ft). When heavy bomb loads were added, this ceiling was reduced to 6,500 m (20,800 ft). The weight of the H-6 increased to 14,000 kg (30,600 lb). Some H-6s received Jumo 211F-2s which improved a low-level speed of 226 mph (365 km/h). At an altitude of 6,000 m (19,200 ft) the maximum speed was 270 mph (435 km/h). If heavy external loads were added, the speed was reduced by 21.75 mph (35 km/h)
Other designs of the mid-H series included the He 111 H-7 and H-8. The airframes were to be rebuilds of the H-3/H-5 variant. Both were designed as night bombers and were to have two Jumo 211F-1s installed. The intention was for the H-8 to be fitted with cable-cutting equipment and barrage ballon deflectors on the leading edge of the wings. The H-7 was never built. The H-9 was intended as a trainer with dual control columns. The airframe was a H-1 variant rebuild. The powerplants consisted of two JumoA-1s or D-1s. The H-10 was also designated to trainer duties. Rebuilt from an H-2 or H-3 airframe, it was installed with full defensive armament including 13 mm (.51 in) MG 131 and 7.92 mm (.312 in) MG 81Z machine guns. It was to be powered by two Jumo 211A-1s, D-1s or F-2s.