Japanese light bombers and reconnaissance aircrafts

The "Glen" was used for several Japanese reconnaissance missions during the Pacific War. It also has the distinction of being the only aircraft to drop bombs on the United States mainland during World War II, in an incident known as The Lookout Air Raid. On 9 September 1942 , Chief Warrant Officer Nobuo Fujita, a pilot in the Japanese Imperial Navy, and his crewman, Petty Officer Shoji Okuda, surfaced in submarine I-25 off the coast of Oregon near Brookings. His tiny seaplane had folding wings and was transported in a small hangar attached to the deck of the submarine. The bombs - 76 kg (168 lb) incendiaries intended to cause forest fires - caused no injuries or real damage. A total of 126 planes were produced.

The E2N was developed in the 1920s for the Imperial Japanese Navy as a short range reconnaissance floatplane suitable for catapult launch from cruisers and battleships. It was a wooden twin-float sesquiplane, carrying a crew of two in open cockpits and having folding wings. This layout gave better downwards view than the monoplanes proposed by Aichi and Yokosuka, and the design was selected becoming Japan's first locally-designed shipboard reconnaissance aircraft. The E2N served with the Navy as the Type 15 Reconnaissance Floatplane (一五式水上偵察機). 80 examples were produced between 1927 and 1929 by Nakajima and Kawanishi; of these, two were bought for civil fishery patrol duties. The Navy machines were withdrawn from front-line units in the 1930s, being replaced by the Nakajima E4N, and either being reassigned to training duties or sold to civil buyers.

The first prototype of this equal-span biplane reconnaissance aircraft appeared in 1930 as the Type 90-2 Reconnaissance Floatplane, company designation NZ. Intended for navy service as the Nakajima E4N1, it had twin flpats and an uncowled Kotobuki radial engine. This first prototype, however, was rejected in favour of the NJ or Navy Type 90-2-2 Reconnaissance Floatplane. This was a complete redesign, with a single main float and twin wingtip stabilising floats. It closely resembles the US Vought O3U-1 Corsair biplane and, like it, was intended for shipboard use and catapult launching. Powered by a 336kW Nakajima Kotobuki radial engine, the Type 90-2-2 had a maximum speed of 222km/h and 85 went into service with the Japanese navy as the E4N2 between 1931 and 1933, a version with fixed wheel landing gear going into service as the E4N2-C; 67 of the latter were completed. In 1933 nine of the E4N2-C landplanes were converted as night mail carriers, for use between the main islands of Japan. Designated P-1, the mail carrier was a single-seater with the pilot accommodated in an enclosed cockpit.

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The E8N was developed as a replacement for the same company's E4N and was essentially an evolutionary development of the earlier type, with revised wings of lesser area and taller tail surfaces. Seven prototypes were constructed, under the company designation MS, first flying in March 1934. These were duly engaged in comparative trials against competitors from Aichi and Kawanishi. The MS was ordered into production, designated Navy Type 95 Reconnaissance Seaplane Model 1 in October 1935.[2] A total of 755 E8Ns were built by Nakajima and Kawanishi, production continuing until 1940. It was subsequently shipped aboard all the capital ships then in service, 16 cruisers and five seaplane tenders.

It was used successfully in the Second Sino-Japanese War not only for reconnaissance, but also for dive-bombing and artillery spotting. One E8N was purchased in early 1941 by the German Naval Attache to Japan, Vice-Admiral Wenneker, and dispatched on board KM MUNSTERLAND to rendezvous with the German auxiliary cruiser Orion at Maug Island in the Marianas. The meeting occurred on 1 FEB 1941, and Orion thus became the only German naval vessel of the Second World War to employ a Japanese float plane. Some aircraft remained in service with the fleet at the outbreak of the Pacific War but they were soon replaced by more modern aircraft such as the Aichi E13A and the Mitsubishi F1M, being reassigned to second-line duties.

Roughly equivalent to the American Curtiss SOC Seagull observation float biplane, the smaller Mitsubishi F1M was of more compact and neater design, its development starting about two years later in 1934. First flown in June 1936, the F1M1 embodied all the efforts of its designers to achieve an exceptionally clean aerodynamic shape, including low-drag float mountings, single interplane struts and all-metal construction, only the control surfaces being fabric-covered. The early aircraft displayed poor water handling and a lack of in-flight directional stability, however, but after fairly extensive alterations the production F1M2 emerged as a thoroughly efficient aircraft, acceptable in all respects.

Initial production by Mitsubishi, which got under way in 1938, amounted to 524 aircraft before it was transferred to the 21st Naval Air Arsenal (Dai-Nijuichi Kaigun Kokusho) at Sasebo, where a further 590 were built. In due course the F1M2 equipped all but one of the K-Maru (6,900-ton) and S-Maru (7,200/8,300-ton) classes of converted merchant seaplane tenders, as well as numerous battleships and cruisers of the Imperial Japanese Navy. Codenamed 'Pete' by the Allies, FlM2s were present at the Battle of Midway, two aircraft being launched from the battleship Kirishima (but being lost when the Japanese scuttled the sorely-crippled ship at the end of the Battle of the Solomons). The giant superbattleships Musashi and Yamato each carried several 'Petes' to spot for their 460mm main gun armament at the time of the Marianas battles, but none was used in earnest; instead the Musashi succumbed to American bombs and torpedoes in the Sibuyan Sea; the Yamato, bent on a suicide mission to Okinawa, followed her to the bottom on 7 April 1945.

Nevertheless 'Pete' seaplanes were widely used throughout the Pacific war, accompanying every seaborne landing by Japanese forces, providing gunnery spotting during preliminary bombardment by supporting warships and subsequently serving as covering fighters (and even dive-bombers) once the assault forces were ashore. It was also flown on convoy escort duties with the many supply convoys sailed by the Japanese during the mid-war period. In the last stages of the war, the type was committed to the unequal task of defending the Japanese homeland from the devastating American raids, serving alongside 'Rex' and 'Rufe' seaplane fighters with the Otsu Kokutai in 1945.

In 1932 the Imperial Japanese Navy requested the Kawanishi Aircraft Company to produce a replacement for the companies Kawanishi E5K. The resulting design, designated the Kawanishi E7K1, was an equal span biplane powered by a 462kW (620hp) Hiro Type 91 W-12 liquid-cooled inline engine. The first aircraft flew on 6 February 1933 and was handed over the navy for trials three-months later. It was flown in competition with the Aichi AB-6 which was designed to meet the same 7-Shi requirement. The E7K1 was ordered into production as the Navy Type 94 Reconnaissance Seaplane (九四式水上偵察機) and entered service in early 1935. It became a popular aircraft, but was hindered by the unreliability of the Hiro engine. Later production E7K1s were fitted with a more powerful version of the Hiro 91, but this did not improve the reliability. In 1938 Kawanishi developed an improved E7K2 with a Mitsubishi Zuisei 11 radial engine, it first flew in August 1938 and was ordered by the Navy as the Navy Type 94 Reconnaissance Seaplane Model 2. The earlier E7K1 was renamed to Navy Type 94 Reconnaissance Seaplane Model 1.

The type was used extensively by the Japanese Navy from 1938 until the beginning of the Pacific War, when E7K1 were relegated to second-line duties. The E7K2 continued in front-line service until 1943 and both versions were used in Kamikaze operations in the closing stages of the war.

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Thanks! Great stuff. The serial photos of the Kawanishi E7K in the middle are official IJN photographs but none of the type designation or service name as well as the other technical details were attached, and captioned only as "A newest naval recon-plane." This is an example of how the military before and during WW2 informed of the general public as "subordinate citizens."

The Aichi M6A Seiran is the only aircraft to have been designed as a submarine-based attack aircraft and to have entered service, although its only military operation was ended prematurely by the end of the Second World War. The idea of building large submarines capable of carrying attack aircraft across the Pacific first emerged late in 1941, and originated with Admiral Isoroku Yamamoto. The design of the I-400 class submarines was completed by March 1942, and in June 1942 it was decided to build 18 of these submarines, each of which would be able to carry three aircraft to any point on the planet. Yamamoto had planned to use these submarines to attack the east coast of the United States, but he was killed in April 1943, only three months after the first submarine – I-400 – was laid down at Kure. Work would eventually begin on five of the submarines, of which three would be completed, but only the first two would ever go to sea. Three M6A Seiran attack aircraft were to be carried in a long watertight cylindrical hanger built into the submarine's superstructure, with the wings folded back against the fuselage and the floats detached.

Aichi were ordered to produce a prototype for the special attack aircraft early in 1942. The new aircraft had to fit within the small submarine hanger, have detachable floats and folding wings, and be capable of being launched by catapult. The floats would be used on training missions, but would be detached on operations. The surviving aircraft would ditch close to their submarines, and the crew would swim back to safety. Aichi's first response was to attempt to modify the D4Y1 Suisei ('Judy'), which they were then producing in large numbers, but this effort failed, and a completely new aircraft had to be developed. The new aircraft looked similar to the Judy, but had a rather more simple structure, to compensate for the limited space on the submarine. It used the Aichi Atsuta Type 32 engine, a licence-built version of the Daimler Benz DB-601A that was never entirely reliable. It would carry a crew of two – pilot and radio operator/ observer/ rear gunner. The folding wings were hydraulically operated, and eventually four trained men could get the aircraft ready for flight in seven minutes.

The M6A prototype made its first flight on 8 December 1943. A number of problems with the design were discovered, and eventually eight prototypes were completed before the aircraft was considered satisfactory. Eighteen production M6A1 aircraft were built between October 1944 and July 1945, only enough to equip a third of the submarines originally planned. Two M6A1-K training aircraft were produced, with retractable landing gear in place of the floats. These aircraft were given the popular name Nanzan meaning either "Southern Mountain" (the intended meaning) or "Difficult Delivery".

By 1943 the target for the M6A had changed from American cities to the lock gates at the Atlantic end of the Panama Canal. Two I-400s and two standard fleet submarines (I-13 and I-14) would carry ten aircraft (three each on the I-400s and two each on the other submarines) to a position to the south west of the canal. The aircraft would then cut across the top of South American and dive bomb the lock gates. Work on this plan reached a very advanced stage, and the mission was timetabled for the autumn of 1945, but just before it was due to take place the operation was cancelled in favour of an attack on US Task Force 38, at Ulithi Atoll. This time the submarines left port. I-400 actually reached the rendezvous point off Ulithi Atoll on 16 August and was preparing to launch its M6A1s on the following morning, but at 21.00hrs that evening the Japanese Sixth Fleet formally confirmed the news of the Japanese surrender. The two I-400 class submarines made their way most of the way back to Japan before surrendering to the Americans, having never launched their M6A1s in anger.

In June 1937, The Imperial Japanese Navy issued a specification to the Aichi, Nakajima, and Kawanishi companies calling for a two-seat reconnaissance floatplane of monoplane configuration to replace the aging Kawanishi E7K2 three-seat twin-float seaplane. The three manufacturers responded with three prototype designs designated E12A, E12N, and E12K, respectively. But even as these three designs were being created, a new specification was issued calling for a larger, three-seat monoplane reconnaissance seaplane, with higher speed and longer range for convoy escort duty. Three additional designs were created by the engineering teams of the companies involved, intending to compliment rather than replace earlier designs. These were designated Aichi E13A, Nakajima E13N, and Kawanishi E13K. Aichi was the only one to build both of its designs with Nakajima deciding to concentrate on the two-seat version while Kawanishi concentrated on the three-seat version.

Kishiro Matsuo's design team created both the E12A and the E13A, the latter being merely a larger and more powerful version of the former. The first E13A was completed in late 1938 add powered by a 1,080 hp (805 kW) Mitsubishi Kinsei 43 14-cylinder air-cooled radial (which was retained throughout the life of the type). During manufacturer's test flights, it became plain that the E13A was superior to the smaller E12A. Not withstanding its larger size and heavier weight, it was much more stable and manoeuvrable, and also had far better performance. By this time, the Navy had decided they wanted a three-seat aircraft and not a two-seater, so development of the two-seat E12A and E12N was halted. Service test pilots flew the prototype E13A in competition against two prototype E13Ks built by Kawanishi. In December 1940, the E13A was formally declared the winner and was accepted for production as the Navy Type 0 Reconnaissance Seaplane Model 11, or E13A1 Model 11. Aichi built 133 E13A1s through early 1942, when they were ordered to concentrate on building the Yokosuka-designed D4Y carrier dive bomber and recon plane. At that time, primary builder of the E13A became the Watanabe Tekkosho (Watanabe Ironworks Company Limited) which in 1943 was re-organized as Kyushu Hikoki KK (Kyushu Airplane Company Limited). Total aircraft production was 1,418 aircraft. Aichi Tokei Denki KK building 133 aircraft from 1939-42, Watanabe/Kyushu building 1,237 aircraft from 1942-45 and Dai-Juichi Kaigun Kokusho (11th Naval Air Arsenal) building 48 aircraft from 1940-42.

The Aichi E13A1 made its combat debut over China in the autumn of 1941. Operating from the catapults of cruisers and seaplane tenders, aircraft of this type made air attacks on the Canton-Hankow Railroad, and also flew anti-shipping patrols along the China coast. Its next combat sorties were flown over Hawaii, launched from the cruisers Tone, Chikuma, and Kinugasa. Aichi E13A1s flew reconnaissance over the area of Pearl Harbour shortly before the attack, pinpointing the positions of the American ships in the harbour and noting that all was quiet, and the Americans were not on alert. From then on, E13A1s were committed wherever the Japanese Navy was operating. Flying from either ships or shore bases, as required, the E13A1 was quite successful as long as Allied fighter opposition was limited, despite its poor fuel and crew protection and its pitiful defensive armament (a single 7.7 mm (0.303 in) machine gun in the rear cockpit). It could carry either one 551 lbs (250 kg) bomb under the fuselage between the floats, or four wing-mounted 132 lbs (60 kg) bombs or depth charges. Its maximum endurance was almost fifteen hours, giving it a useful range for patrol and reconnaissance missions. In addition to limited bombing strikes and long-range patrol sorties, the "Jake" as she was code-named, also was used for staff transport, air-sea rescue, anti-shipping attack, and, later in the war Kamikaze attacks.

For nearly four years, the Jake was built without any changes from the original prototype. In November 1944, two new subtypes were introduced, differing externally from the regular E13A1 only by the additions of a propeller spinner for the three-bladed propeller, and two extra pairs of inward-sloping bracing struts for the twin underwing floats. The E13A1a Model 11A received improved radio equipment, while the E13A1b Model 11B was fitted with an air-to-surface search radar, with antennae protruding from the fuselage sides and from the wing leading edges. Either of these versions could be fitted with exhaust flame dampers for night operations, and for anti-shipping attack (usually against surfaced submarines or PT boats), a single flexible Type 99 20 mm cannon, firing downwards and forwards from the fuselage belly, could be mounted, as well. Some Jakes were also fitted with an aerial magnetic submarine detection device, called Jikitanchiki, which required the aircraft to fly at a very low 30-40 ft (9-12 m) above the sea's surface to get any decent results.

Due to the theatre the Japanese operated in and the vast expanses of ocean it encompassed, long range seaplanes were crucial to the Japanese war effort. The Aichi E13A served from Pearl harbour to some of the last Kamikaze attacks of the war. Although easy fodder for Allied fighters the Aichi E13A and its crews performed their missions well throughout the Pacific War.

The Aichi E16A originated from a 1939 specification for an replacement for the Aichi E13A, which at that time had yet to be accepted by the Imperial Japanese Navy Air Service (IJNAS).[2] Disagreements about the requirements in the 14-Shi specification prevented most manufacturers from submitting designs, but in 1941 a new 16-Shi specification was drafted by the IJNAS around the Aichi AM-22 design which had already been made by Aichi engineers Kishiro Matsuo and Yasuhiro Ozawa.[2] The first AM-22, which first got the experimental designation Navy Experimental 16-Shi Reconnaissance Seaplane and later the short designation E16A1, was completed by May 1942 and was a conventional, low-wing monoplane equipped with two floats and had the unusual (for a seaplane) feature of being equipped with dive brakes, located in the front legs of the float struts, to allow it to operate in a secondary role as a dive bomber.

In mid-1938 the Japanese Imperial Navy requested a twin-engine fighter designed to escort the principal bomber used at the time, Mitsubishi G3M "Nell". The operating range of the standard Navy fighter, the Mitsubishi A5M "Claude", was only 1,200 km (750 mi), insufficient compared with the 4,400 km (2,730 mi) of the G3M. Moreover, at the time, the potential of the "Zero", then still under development, remained to be evaluated, stressing the need for a long-range escort fighter. In March 1939, Mitsubishi and Nakajima began the development of a project 13-Shi. The prototype left the factory in March 1941 equipped with two 843 kW (1,130 hp) Nakajima Sakae 21/22, 14-cylinder radial engines. There was a crew of three, and the aircraft was armed with a 20 mm Type 99 cannon and six 7.7 mm (.303 in) Type 97 machine guns. Four of these machine guns were mounted in a powered turret, the weight of which reduced the performance of the aircraft considerably. Because of the sluggish handling, being used as ae escort fighter had to be abandoned. Instead, production was authorized for a lighter reconnaissance variant, the J1N1-C, also known by the Navy designation Navy Type 2 Reconnaissance Plane. One early variant, the J1N1-F, had a spherical turret with one 20 mm Type 99 Model 1 cannon mounted immediately behind the pilot. In 1943, Commander Yasuna Kozono（小園 安名） of the 251st Kokutai in Rabaul came up with the idea of installing 20 mm cannons at 30 degree angle in the fuselage. Against orders of central command which was skeptical of his idea, he tested his idea on a J1N1-C as a night fighter. The field-modified J1N1-C KAI shot down two B-17s of 43rd Bomb Group attacking air bases around Rabaul on 21 May 1943.

The Navy took immediate notice and placed orders with Nakajima for the newly designated J1N1-S nightfighter design. This model was christened the Model 11 Gekko (月光, "Moonlight"). It required only two crew and like the KAI, had a twin 20 mm pair of Type 99 Model 1 cannon firing upward in a 30° upward angle and a second pair firing downward at a forward 30° angle, placed in the fuselage behind the cabin, similar to the German Schräge Musik configuration, but also in a ventral mode-the original German Schräge Musik mount was strictly upward-firing only. Development of both Japanese and German night fighters were independent of each other. This arrangement was effective against B-17 Flying Fortress bombers and B-24 Liberators, and its existence was not quickly understood by the allies who assumed the Japanese did not have the technology for night fighter designs. Early versions had nose searchlights in place of radar. Later models omitted the two lower-firing guns and added one 20 mm cannon to face upward as with the other two (J1N1-Sa Model 11a). Other variants without nose antennae or searchlight added a 20 mm cannon to the nose.

The J1N1-S was used against B-29 Superfortresses in Japan, though the lack of good radar and insufficient high-altitude performance handicapped it, since usually only one pass could be made against the higher-speed B-29s. However, some skillful pilots had spectacular successes, such as Lieutenant Sachio Endo, who was credited with destroying eight B-29s and damaging another eight before he was shot down by a B-29 crew, Shigetoshi Kudo (nine victories), Shiro Kuratori (six victories), and Juzo Kuramoto (eight victories); the last two claimed five B-29s during the night of 25–26 May 1945. Another Gekko crew shot down five B-29's in one night, but these successes were rare. Many Gekkos were also shot down or destroyed on the ground. A number of Gekkos were relegated to "Tokko" missions, the Japanese term for kamikaze attacks, using 250 kg (550 lb) bombs attached to the wings.

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Excellent!

Although not a particularly powerful, or technologically advanced aircraft the Aichi D3A Val managed to come as a shock to the Americans when it spearheaded the attack on the American Fleet at Pearl Harbour on 7th December 1941. For the year following Pearl Harbour the Val (protected by Zero fighters) ruled supreme devastating Allied shipping in the South-West Pacific and Indian oceans. This was to last only until it started to come across well defended ships and better Allied fighters and by 1943 the Val had had its day and was no longer feared. The initial shock was mainly due to very poor allied intelligence which had virtually no information on Japanese aircraft and grossly underestimated them. The 'Val' gained its code name from the American system of naming enemy fighters after short boys names, trainers after trees and giving girl's names to bombers. The Val was designed by Tokuhishiro Goake and had an elliptical wing, and no internal bomb storage it also had non retractable landing gear much like the German Stuka dive bomber. Since it was intended as a carrier aircraft the tips of the wings folded for storage. The prototype first flew in 1938 with carrier trials in 1940 and flew operationally during missions in China and Indo-China a fact missed by US intelligence. At Pearl Harbour 126 Val dive bombers took part and the Japanese had over 250 in service by mid 1942. By this period losses were heavy and by 1944 only kamikaze suicide versions were in frontline service. Around 1,495 were finally produced.

In mid-1936, the Japanese Navy issued the 11-Shi specification for a monoplane carrier-based dive bomber to replace the existing D1A biplane currently in service. Aichi, Nakajima and Mitsubishi all submitted designs, and Aichi and Nakajima were both asked for two prototypes each. The Aichi design started with low-mounted elliptical wings inspired by the Heinkel He 70 Blitz. It flew slowly enough that the drag from the landing gear was not a serious issue, so fixed gear were used for simplicity. The aircraft was to be powered by the 529 kW (710 hp) Nakajima Hikari 1 nine-cylinder radial engine. The first prototype was completed in December 1937, and flight trials began a month later. Initial tests were disappointing. The aircraft was underpowered and suffered from directional instability in wide turns, and in tighter turns, it tended to snap roll. The dive brakes vibrated heavily when extended at their design speed of 370 km/h (200 kn), and the Navy was already asking for a faster diving speed of 240 kn (440 km/h). The second aircraft was extensively modified prior to delivery to try to address the problems. Power was increased by replacing the Hikari with the 626 kW (840 hp) Mitsubishi Kinsei 3 in a redesigned cowling, and the vertical tail was enlarged to help with the directional instability. The wings were slightly larger in span and the outer sections of the leading edges had wash-out to combat the snap rolls, and strengthened dive brakes were fitted. These changes cured all of the problems except the directional instability, and it was enough for the D3A1 to win over the Nakajima D3N1.

In December 1939, the Navy ordered the aircraft as the Navy Type 99 Carrier Bomber Model 11 (kanjō bakugekiki, usually abbreviated to 艦爆 kanbaku). The production models featured slightly smaller wings and increased power in the form of the 746 kW (1,000 hp) Kinsei 43 or 798 kW (1,070 hp) Kinsei 44. The directional instability problem was finally cured with the fitting of a long dorsal fin, and the aircraft actually became highly maneuverable. Armament was two forward-firing 7.7 mm (.303 in) Type 97 machine guns, and one flexible 7.7 mm (.303 in) Type 92 machine gun in the rear cockpit for defense. Normal bombload was a single 250 kg (550 lb) bomb carried under the fuselage, which was swung out under the propeller on release by a trapeze. Two additional 60 kg (130 lb) bombs could be carried on wing racks located under each wing outboard of the dive brakes.

The D3A1 commenced carrier qualification trials aboard the Akagi and Kaga during 1940, while a small number of aircraft made their combat debut from land bases over China. Starting with the attack on Pearl Harbor, the D3A1 took part in all major Japanese carrier operations in the first 10 months of the war. They achieved their first major success against the Royal Navy during their Indian Ocean raid in April 1942. Val dive bombers scored over 80% hits with their bombs during attacks on two heavy cruisers and an aircraft carrier during the operation. During the course of the war, Val dive bombers had to frequently combine their attacks upon enemy warships with the IJN Kate torpedo plane; consequently enemy vessels were often sunk by a combination strike of bombs and torpedoes. However, there were occasions when just the Vals would make the attacks, or at least score the sinking hits.

As the war progressed, there were instances when the dive bombers were pressed into duty as fighters, their maneuverability being enough to allow them to survive in this role. In June 1942, an improved version of the D3A powered by a 969 kW (1,300 hp) Kinsei 54 was tested as the Model 12. The extra power reduced range, so the design was further modified with additional fuel tanks to bring the total tankage to 900 L (240 US gal, giving it the range needed to fight effectively over the Solomon Islands. Known to the Navy as the Model 22, it began to replace the Model 11 in front-line units in autumn 1942, and most Model 11s were then sent to training units. When the Yokosuka D4Y Suisei became available, the D3A2s ended up with land-based units or operating from the smaller carriers, which were too small to handle the fast-landing Suisei. When American forces recaptured the Philippines in 1944, land-based D3A2s took part in the fighting, but were hopelessly outdated and losses were heavy. By then, many D3A1s and D3A2s were operated by training units in Japan, and several were modified with dual controls as Navy Type 99 Bomber Trainer Model 12s (D3A2-K). During the last year of the war, the D3A2s were pressed back into combat for kamikaze missions.

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