Heinkel A7He
Encyclopedia
The A7He Type He Air Defense Fighter was the Japanese designation for a variant of the German Heinkel He 112
.
In the late 1930s, with its military at war in China
, Japan
saw a need for aircraft with higher performance than then available. A number of foreign aircraft were imported and tested to discover the technology and manufacturing techniques that were used abroad. One of the aircraft that was tested was the Heinkel He 112. Japan placed an order for 24 aircraft. Once they arrived in Japan, the Imperial Japanese Navy
designated these aircraft as A7He Type He Air Defense Fighter.
sent out a letter requesting aircraft companies to design a "high speed courier aircraft" - a thinly veiled request for a new fighter. In May 1934, this was made official and the Technisches Amt sent out a request for a single-seat interceptor
for the Rüstungsflugzeug IV role, this time under the guise of a "sports aircraft". The specification was first sent to the three most experienced fighter designers, Heinkel, Arado, and Focke-Wulf. It was also sent to newcomer Bayerische Flugzeugwerk (Bavarian Aircraft Manufacturers or BFW) on the strength of their Bf 108
Taifun advanced sportsplane design. Each company was asked to build three prototype
s for run-off testing.
radial engine. Work was already under way when the official request went out on 2 May. On 5 May the design was renamed He 112
.
("Lightning") design. The Blitz was a single-engine, four-passenger aircraft inspired by the famous Lockheed Model 9 Orion mail plane. The Blitz was originally designed for use by Deutsche Lufthansa
, but it was pressed into military service and was used as a two-seat bomber
(although mostly for reconnaissance) and served in this role in Spain.
The Blitz introduced a number of new construction techniques to the Heinkel company; it was their first low-wing monoplane
, their first with retractable landing gear, their first all-metal monocoque design, and its elliptical, reverse-gull wing
planform
all of which would be seen on a number of later projects. The Blitz could almost meet the new fighter requirements itself, so it is not surprising that the Günters would choose to work with the existing design as much as possible.
inverted V12 engine mounting a two-blade propeller and were armed with two 7.9 mm MG 17 machine guns. V4 (D-IZMY) mounted a 690 hp Junkers Jumo 210Da
inverted V12 engine and mounted three MG 17s, becoming the production prototype for the proposed He 112A.
In many ways, the resulting He 112 design was a scaled-down He 70. Like the He 70, the He 112 was constructed entirely of metal, using a two-spar wing and a monocoque fuselage with flush-head rivets. The landing gear retracted outward from the low point of the wing's gull-bend, which resulted in a fairly wide 9 m (30 ft) track, giving the aircraft excellent ground handling. Its only features from an older era were its open cockpit
and fuselage spine behind the headrest, which provided excellent vision and made the biplane-trained pilots feel more comfortable.
By spring 1935, both the Arado
and Focke-Wulf
aircraft were ready for run-off testing, the BFW arriving in March, and the He 112 in April. Testing continued until October, at which point some of the additional A-0 series aircraft had arrived.
At the end of September, there were four He 112s undergoing test, yet none was a match for the Bf 109. From October on, the Bf 109 appears to have been selected as the winner of the contest. Although no clear date is given, in Stormy Life Ernst Udet
himself delivered the news to Heinkel that the Bf 109 had entered series production in 1936. He is quoted as saying, "Pawn your crate off on the Turks or the Japs or the Rumanians. They'll lap it up." With a number of air forces looking to upgrade from biplanes and various designs from the early 1930s, the possibility for foreign sales was promising.
Prototypes V5 (D-?), V6 (D-ISJY), and V7 (D-IKIK) were powered by the 690 hp Junkers Jumo 210Da
inverted V12 engine and were prototypes for the He 112A. The last of the prototype He 112A-0 series was V8 (D-IXRO), which was completed in October. It mounted the Daimler-Benz DB 600Aa inverted V12 engine, along with a three-blade, fully adjustable, all-metal propeller. The engine was a huge change for the aircraft, producing 716 kW (960 hp) for takeoff and had 33.9 L (2,069 in³) displacement weighing 686 kg (1,510 lb), compared to the Junkers Jumo 210Da's
514 kW (690 hp) from 19.7 L (1,202 in³) at about the same weight.
Prototype V8 was seen primarily as a testbed for the new engine, and more importantly, its cooling systems. The DB engine used a dry type cylinder liner that resulted in poor heat flow, so more of the heat was removed by oil as opposed to water, this in turn required changes to the cooling systems.
These aircraft were used in a varied a manner as were the earlier V series aircraft. A-01 flew in October 1936 and was used as the prototype for a future 112C-0 carrier-based aircraft
. A-02 flew in November, and then joined the earlier V models at Rechlin-Lärz Airfield
for further testing in the contest. A-03 and A-04 were both completed in December, A-03 was a show aircraft and was flown by Heinkel pilots at various air shows and exhibitions, A-04 was kept at Heinkel for various tests.
The last two models of the He 112A-0 series, A-05 and A-06, were completed in March 1937. They were shipped to Japan as the initial aircraft of the 30 ordered by the Imperial Japanese Navy. Like all of the other He 112As, they had Jumo 210C engine and open cockpits.
inverted V12 engine. V9 can be considered to be the "real" B series prototype. The entire surface was now flush riveted and the aircraft had several other aerodynamic cleanups, including a bubble canopy
. The radiator was again changed, this time to a semi-retractable design for reduced drag in flight. The aircraft also underwent a weight reduction program which reduced the empty weight to 1,617 kg (3,565 lb).
As a result of all of these changes, the V9 had a maximum speed of 485 km/h (301 mph) at 4,000 m (13,120 ft), and 430 km/h (270 mph) at sea level. This was a full 20 km/h (10 mph) faster than the contemporary Bf 109B
. Nevertheless, by this time, the Bf 109 was already ramping up production, and the RLM saw no need for another largely similar aircraft. It is also worth noting that users of the aircraft generally found it impossible to reach this speed, and rarely managed to exceed 418 km/h (260 mph).
In order to show off the He 112, prototype V9 spent much of the later half of 1937 being flown by pilots from all over the world. It was also sent around Europe for tours and air shows. The effort was a success and orders quickly started coming in. However, a variety of problems meant few of these were ever delivered.
bombers over China. After seeing V9 in flight, they quickly placed an order for 24 112Bs, with an option for 48 more. The first four were shipped in December 1937, another eight in the spring of 1938, and promises for the rest to arrive in May. A 13th aircraft, He 112-V12 (D-IYWE) with its DB 600Aa engine, was also purchased by Japan.
Before the last 12 could be delivered to Japan, the Luftwaffe unexpectedly confiscated them to bolster its forces during the Sudetenland Crisis. The aircraft were returned to Heinkel in November, but the Japanese were unhappy with the high maintenance workload and lower maneuverability of the He 112 when compared to fighters like the Mitsubishi A5M, refusing to accept them this late, leaving Heinkel holding the aircraft.
Although the Japanese rejected the He 112 as a fighter. Those that did arrive in Japan were assigned to mechanic training duties at Tsuchiura Naval Station.
Heinkel He 112
The Heinkel He 112 was a fighter aircraft designed by Walter and Siegfried Günter. It was one of four aircraft designed to compete for the Luftwaffes 1933 fighter contract, which was eventually won by the Messerschmitt Bf 109...
.
In the late 1930s, with its military at war in China
Second Sino-Japanese War
The Second Sino-Japanese War was a military conflict fought primarily between the Republic of China and the Empire of Japan. From 1937 to 1941, China fought Japan with some economic help from Germany , the Soviet Union and the United States...
, Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
saw a need for aircraft with higher performance than then available. A number of foreign aircraft were imported and tested to discover the technology and manufacturing techniques that were used abroad. One of the aircraft that was tested was the Heinkel He 112. Japan placed an order for 24 aircraft. Once they arrived in Japan, the Imperial Japanese Navy
Imperial Japanese Navy
The Imperial Japanese Navy was the navy of the Empire of Japan from 1869 until 1947, when it was dissolved following Japan's constitutional renunciation of the use of force as a means of settling international disputes...
designated these aircraft as A7He Type He Air Defense Fighter.
Design and development
In October 1933, Hermann GöringHermann Göring
Hermann Wilhelm Göring, was a German politician, military leader, and a leading member of the Nazi Party. He was a veteran of World War I as an ace fighter pilot, and a recipient of the coveted Pour le Mérite, also known as "The Blue Max"...
sent out a letter requesting aircraft companies to design a "high speed courier aircraft" - a thinly veiled request for a new fighter. In May 1934, this was made official and the Technisches Amt sent out a request for a single-seat interceptor
Interceptor aircraft
An interceptor aircraft is a type of fighter aircraft designed specifically to prevent missions of enemy aircraft, particularly bombers and reconnaissance aircraft. Interceptors generally rely on high speed and powerful armament in order to complete their mission as quickly as possible and set up...
for the Rüstungsflugzeug IV role, this time under the guise of a "sports aircraft". The specification was first sent to the three most experienced fighter designers, Heinkel, Arado, and Focke-Wulf. It was also sent to newcomer Bayerische Flugzeugwerk (Bavarian Aircraft Manufacturers or BFW) on the strength of their Bf 108
Messerschmitt Bf 108
-Popular culture:Bf 108s and postwar Nord 1000s, played the role of Messerschmitt Bf 109 fighters in war movies, including The Longest Day, 633 Squadron, Von Ryan's Express and Indiana Jones and the Last Crusade.-See also:-References:Notes...
Taifun advanced sportsplane design. Each company was asked to build three prototype
Prototype
A prototype is an early sample or model built to test a concept or process or to act as a thing to be replicated or learned from.The word prototype derives from the Greek πρωτότυπον , "primitive form", neutral of πρωτότυπος , "original, primitive", from πρῶτος , "first" and τύπος ,...
s for run-off testing.
Projeckt 1015
Heinkel's design was created primarily by twin brothers Siegfried and Walter Günter, whose designs would dominate most of Heinkel's work. They started work on Projekt 1015 in late 1933 under the guise of the original request for a courier aircraft that was based around the BMW XVBMW 117
The BMW 117 was a piston aircraft engine developed by BMW in the 1930s. Development work stopped in 1937. The BMW 117 engine was initially known as the BMW XV.-Specifications :-See also:|lists=*List of aircraft engines...
radial engine. Work was already under way when the official request went out on 2 May. On 5 May the design was renamed He 112
Heinkel He 112
The Heinkel He 112 was a fighter aircraft designed by Walter and Siegfried Günter. It was one of four aircraft designed to compete for the Luftwaffes 1933 fighter contract, which was eventually won by the Messerschmitt Bf 109...
.
He 70 Blitz
The primary source of inspiration for the He 112 is their earlier He 70 BlitzHeinkel He 70
The Heinkel He 70 was a German mail plane and fast passenger aircraft of the 1930s, that also saw use in auxiliary bomber and reconnaissance roles. It had a relatively brief commercial career before it was replaced by types which could carry more passengers...
("Lightning") design. The Blitz was a single-engine, four-passenger aircraft inspired by the famous Lockheed Model 9 Orion mail plane. The Blitz was originally designed for use by Deutsche Lufthansa
Deutsche Luft Hansa
Deutsche Luft Hansa A.G. was a German airline, serving as flag carrier of the country during the later years of the Weimar Republic and throughout the Third Reich.-1920s:Deutsche Luft Hansa was founded on 6 January 1926 in Berlin...
, but it was pressed into military service and was used as a two-seat bomber
Bomber
A bomber is a military aircraft designed to attack ground and sea targets, by dropping bombs on them, or – in recent years – by launching cruise missiles at them.-Classifications of bombers:...
(although mostly for reconnaissance) and served in this role in Spain.
The Blitz introduced a number of new construction techniques to the Heinkel company; it was their first low-wing monoplane
Monoplane
A monoplane is a fixed-wing aircraft with one main set of wing surfaces, in contrast to a biplane or triplane. Since the late 1930s it has been the most common form for a fixed wing aircraft.-Types of monoplane:...
, their first with retractable landing gear, their first all-metal monocoque design, and its elliptical, reverse-gull wing
Gull wing
The gull wing is an aircraft's wing configuration with a prominent bend in the wing somewhere along the span, generally near the wing root. Its name is derived from the seabirds which it resembles. It has been incorporated in aircraft for many reasons....
planform
Planform
In aviation, a planform is the shape and layout of a fixed-wing aircraft's fuselage and wing. Of all the myriad planforms used, they can typically be grouped into those used for low-speed flight, found on general aviation aircraft, and those used for high-speed flight, found on many military...
all of which would be seen on a number of later projects. The Blitz could almost meet the new fighter requirements itself, so it is not surprising that the Günters would choose to work with the existing design as much as possible.
He 112 Prototypes
The He 112 prototypes were named He 112V1 through V4. He 112V1 (D-IADO) was powered with a 695 hp Rolls-Royce Kestrel V engine, and was completed in the summer of 1935. Prototype V2 (D-?) had its wingspan reduced from 41 ft 4 in to 37 ft 8 3/4 in, which became the standard wingspan for all future airframes. Prototypes V2 and V3 (D-IDMO) received a 620 hp Jumo 210CJunkers Jumo 210
The Jumo 210 was Junkers Motoren's first production inverted V12 gasoline aircraft engine, produced just before the start of World War II. Depending on version it produced between 610 and 700 PS and can be considered a counterpart of the Rolls-Royce Kestrel in many ways...
inverted V12 engine mounting a two-blade propeller and were armed with two 7.9 mm MG 17 machine guns. V4 (D-IZMY) mounted a 690 hp Junkers Jumo 210Da
Junkers Jumo 210
The Jumo 210 was Junkers Motoren's first production inverted V12 gasoline aircraft engine, produced just before the start of World War II. Depending on version it produced between 610 and 700 PS and can be considered a counterpart of the Rolls-Royce Kestrel in many ways...
inverted V12 engine and mounted three MG 17s, becoming the production prototype for the proposed He 112A.
In many ways, the resulting He 112 design was a scaled-down He 70. Like the He 70, the He 112 was constructed entirely of metal, using a two-spar wing and a monocoque fuselage with flush-head rivets. The landing gear retracted outward from the low point of the wing's gull-bend, which resulted in a fairly wide 9 m (30 ft) track, giving the aircraft excellent ground handling. Its only features from an older era were its open cockpit
Cockpit
A cockpit or flight deck is the area, usually near the front of an aircraft, from which a pilot controls the aircraft. Most modern cockpits are enclosed, except on some small aircraft, and cockpits on large airliners are also physically separated from the cabin...
and fuselage spine behind the headrest, which provided excellent vision and made the biplane-trained pilots feel more comfortable.
By spring 1935, both the Arado
Arado Flugzeugwerke
Arado Flugzeugwerke was a German aircraft manufacturer, originally established as the Warnemünde factory of the Flugzeugbau Friedrichshafen firm, that produced military hydroplanes during the First World War.-History:...
and Focke-Wulf
Focke-Wulf
Focke-Wulf Flugzeugbau AG was a German manufacturer of civil and military aircraft before and during World War II. Many of the company's successful fighter aircraft designs were slight modifications of the Focke-Wulf Fw 190.-History:...
aircraft were ready for run-off testing, the BFW arriving in March, and the He 112 in April. Testing continued until October, at which point some of the additional A-0 series aircraft had arrived.
At the end of September, there were four He 112s undergoing test, yet none was a match for the Bf 109. From October on, the Bf 109 appears to have been selected as the winner of the contest. Although no clear date is given, in Stormy Life Ernst Udet
Ernst Udet
Colonel General Ernst Udet was the second-highest scoring German flying ace of World War I. He was one of the youngest aces and was the highest scoring German ace to survive the war . His 62 victories were second only to Manfred von Richthofen, his commander in the Flying Circus...
himself delivered the news to Heinkel that the Bf 109 had entered series production in 1936. He is quoted as saying, "Pawn your crate off on the Turks or the Japs or the Rumanians. They'll lap it up." With a number of air forces looking to upgrade from biplanes and various designs from the early 1930s, the possibility for foreign sales was promising.
Prototypes
The remaining prototypes (V5 through V12) received bubble canopies with lowered upper fuselage spines.Prototypes V5 (D-?), V6 (D-ISJY), and V7 (D-IKIK) were powered by the 690 hp Junkers Jumo 210Da
Junkers Jumo 210
The Jumo 210 was Junkers Motoren's first production inverted V12 gasoline aircraft engine, produced just before the start of World War II. Depending on version it produced between 610 and 700 PS and can be considered a counterpart of the Rolls-Royce Kestrel in many ways...
inverted V12 engine and were prototypes for the He 112A. The last of the prototype He 112A-0 series was V8 (D-IXRO), which was completed in October. It mounted the Daimler-Benz DB 600Aa inverted V12 engine, along with a three-blade, fully adjustable, all-metal propeller. The engine was a huge change for the aircraft, producing 716 kW (960 hp) for takeoff and had 33.9 L (2,069 in³) displacement weighing 686 kg (1,510 lb), compared to the Junkers Jumo 210Da's
Junkers Jumo 210
The Jumo 210 was Junkers Motoren's first production inverted V12 gasoline aircraft engine, produced just before the start of World War II. Depending on version it produced between 610 and 700 PS and can be considered a counterpart of the Rolls-Royce Kestrel in many ways...
514 kW (690 hp) from 19.7 L (1,202 in³) at about the same weight.
Prototype V8 was seen primarily as a testbed for the new engine, and more importantly, its cooling systems. The DB engine used a dry type cylinder liner that resulted in poor heat flow, so more of the heat was removed by oil as opposed to water, this in turn required changes to the cooling systems.
He 112A Production models
At this point, the prototype stage was winding down. Heinkel continued building the A-0 as production line models. The model naming scheme changed by adding a production number to the end of the model name, so the next six examples were known as He 112A-01 through A-06. All of these included the Jumo 210C engine and were essentially identical to V6, with the exception of the radiator.These aircraft were used in a varied a manner as were the earlier V series aircraft. A-01 flew in October 1936 and was used as the prototype for a future 112C-0 carrier-based aircraft
Carrier-based aircraft
Carrier-based aircraft are military aircraft designed specifically for operations from aircraft carriers. The term is generally applied only to fixed-wing aircraft, as naval helicopters are able to operate from a wider variety of aviation-capable ships. Carrier-based aircraft must be relatively...
. A-02 flew in November, and then joined the earlier V models at Rechlin-Lärz Airfield
Rechlin-Lärz Airfield
Rechlin-Lärz Airfield is an airfield in the village of Rechlin, Mecklenburg-Western Pomerania, Germany, which is certified for aviation equipment up to 14 tons weight...
for further testing in the contest. A-03 and A-04 were both completed in December, A-03 was a show aircraft and was flown by Heinkel pilots at various air shows and exhibitions, A-04 was kept at Heinkel for various tests.
The last two models of the He 112A-0 series, A-05 and A-06, were completed in March 1937. They were shipped to Japan as the initial aircraft of the 30 ordered by the Imperial Japanese Navy. Like all of the other He 112As, they had Jumo 210C engine and open cockpits.
Prototypes
The next prototype airframe, V9 (D-IJSI), first flown in July 1937, was powered by the 507 kW (680 hp) Jumo 210EaJunkers Jumo 210
The Jumo 210 was Junkers Motoren's first production inverted V12 gasoline aircraft engine, produced just before the start of World War II. Depending on version it produced between 610 and 700 PS and can be considered a counterpart of the Rolls-Royce Kestrel in many ways...
inverted V12 engine. V9 can be considered to be the "real" B series prototype. The entire surface was now flush riveted and the aircraft had several other aerodynamic cleanups, including a bubble canopy
Bubble canopy
A bubble canopy is a canopy made like a soap bubble, which attempts to provide 360° vision to the pilot.-History:Bubble canopies have been in use since World War II. The British had already developed the "Malcolm hood", which was a bulged canopy, but the British Miles M.20 was one of the first...
. The radiator was again changed, this time to a semi-retractable design for reduced drag in flight. The aircraft also underwent a weight reduction program which reduced the empty weight to 1,617 kg (3,565 lb).
As a result of all of these changes, the V9 had a maximum speed of 485 km/h (301 mph) at 4,000 m (13,120 ft), and 430 km/h (270 mph) at sea level. This was a full 20 km/h (10 mph) faster than the contemporary Bf 109B
Messerschmitt Bf 109
The Messerschmitt Bf 109, often called Me 109, was a German World War II fighter aircraft designed by Willy Messerschmitt and Robert Lusser during the early to mid 1930s...
. Nevertheless, by this time, the Bf 109 was already ramping up production, and the RLM saw no need for another largely similar aircraft. It is also worth noting that users of the aircraft generally found it impossible to reach this speed, and rarely managed to exceed 418 km/h (260 mph).
In order to show off the He 112, prototype V9 spent much of the later half of 1937 being flown by pilots from all over the world. It was also sent around Europe for tours and air shows. The effort was a success and orders quickly started coming in. However, a variety of problems meant few of these were ever delivered.
Production models
The first production order was from the Imperial Japanese Navy, who had a requirement for a fast climbing interceptor to deal with Tupolev SBTupolev SB
The Tupolev ANT-40, also known by its service name Tupolev SB , and development co-name TsAGI-40, was a high speed twin-engined three-seat monoplane bomber, first flown in 1934....
bombers over China. After seeing V9 in flight, they quickly placed an order for 24 112Bs, with an option for 48 more. The first four were shipped in December 1937, another eight in the spring of 1938, and promises for the rest to arrive in May. A 13th aircraft, He 112-V12 (D-IYWE) with its DB 600Aa engine, was also purchased by Japan.
Before the last 12 could be delivered to Japan, the Luftwaffe unexpectedly confiscated them to bolster its forces during the Sudetenland Crisis. The aircraft were returned to Heinkel in November, but the Japanese were unhappy with the high maintenance workload and lower maneuverability of the He 112 when compared to fighters like the Mitsubishi A5M, refusing to accept them this late, leaving Heinkel holding the aircraft.
Although the Japanese rejected the He 112 as a fighter. Those that did arrive in Japan were assigned to mechanic training duties at Tsuchiura Naval Station.