Aichi E16A1 Zuiun

The design of a twin-float reconnaissance seaplane, to supersede the E13A1 in service, was initiated by Aichi in October 1940. This had the company designation AM-22, and in early 1941 the Imperial Japanese navy drew up a specification based upon this design. The first of three prototypes was flown for the first time during May 1942, but the resolution of stability problems, and of buffeting from the dive brakes occupied 15 months, the navy ordering the E16A1 into production in August 1943 as the Navy Reconnaissance Seaplane Zuiun Model 11.

Of low-wing monoplane configuration, the E16A1 had wings that incorporated trailing-edge flaps, and which could be folded for shipboard stowage. Basic structure was of metal, but the tailplane and wingtips were of wood, and all control surfaces were fabric covered. The single-step floats each included a controllable rudder to assist in on-water operation, and the forward mounting strut of the floats incorporated by hydraulically-actuated dive brakes to allow the E16A1 to operate as a dive-bomber. Accommodation for the crew of two was provided in tandem cockpits, enclosed by a long transparent canopy. Powerplant of the prototype and of early production Zuiun (auspicious cloud) aircraft consisted of a 1,300-hp (969-kW) Mitsubishi Kinsei 51 radial engine, driving a three-blade propeller. A single prototype of an improved E16A2 was being flight tested at the time of the Japanese surrender, powered by a 1,560-hp (1163-kW) Mitsubishi MK8P Kinsei 62 radial engine.

Production totalled 193 by Aichi and 59 by Nippon. Unfortunately for the navy, by the time the E16A1 entered service the Allies had gained air superiority and in consequence these aircraft, allocated the Allied codename 'Paul', suffered very heavy losses during 1944. The majority which survived were used for kamikaze operations in the Okinawa area.

Specification

Aichi E16A1 (late production)

Type: long-range reconnaissance floatplane

Powerplant: one 1,300-hp (969-kW) Mitsubishi MK8D Kinsei 54 14-cylinder radial piston engine

Performance: maximum speed at 18,045 ft (5500 m) 273 mph (440 km/h); cruising speed at 16,405 ft (5000 m) 208 mph (335 km/h); service ceiling 32,810 ft (10000 m); maximum range, 1,504 miles (2420 km)

Weights: empty 6,4931b (2945 kg); maximum take-off 10,038 lb (4553 kg)

Dimensions: span 42 ft 0 ¼ in (12.81 m); length 35 ft 6 ½ in (10.83 m); height 15 ft 8 ½ in (4.79 m); wing area 301.40 sq ft (28.00 m2)

Armament: two 20-mm wing-mounted Type 99 Model 2 cannon and one 13-mm (0.51-in) Type 2 machine-gun on flexible mount in aft position, plus one 551-lb (250-kg) bomb on under fuselage mounting

Operator: Japanese navy

Variants

E16A1

    Main production version.

E16A2

    Single prototype with Kinsei 62 piston engine.

Kawanishi H8K

Soon after the first three Kawanishi H6K2s entered service in January 1938, the Imperial Japanese Navy issued a development contract to the company for a new large flying-boat to serve as a replacement for that aircraft, appreciating that it would be two or three year before a prototype would emerge. The estimate was fairly accurate, the Kawanishi H8K1 prototype making a first flight on the last day of December 1940, and while like its predecessor it was powered by four engines, in other respects it differed considerably. The high-set cantilever monoplane wing tapered in both chord and thickness from wing root to wingtip and served also to mount strutted and braced underwing stabilising floats at about two-thirds span. The hull was more conventional, losing the graceful lines of the H6K, and mounted at its rear a tail unit with single fin and rudder. Power for the three prototypes and early production aircraft was provided by four Misubishi MK4A Kasei (Mars) 11 radial engines mounted in nacelles at the wing leading edge. Accommodation was provided for a crew of 10, and defensive armament comprised five 20-mm cannon in port and starboard blisters and in nose, dorsal and tail turrets, supplemented by three 7.7-mm (0.303-in) machine-guns in two side hatches and a ventral position. Comprehensive armour protection was provided and the bulk fuel tanks within the hull were partially self-sealing and incorporated a carbon dioxide fire-extinguishing system.

The H8K was, therefore, an advanced aircraft, and designed to a specification that called for performance superior to that of the Short Sunderland. Not surprisingly, Kawanishi was greatly disappointed with early tests which showed that the first of the H8K1 prototypes was dangerously unstable on the water. Modifications were begun immediately to rectify this situation, including an increase in hull depth of 1 ft 9 3/4 in (0.55 m). New tests showed considerable improvement, but the second and third prototypes introduced the deeper hull and additional less major hull modifications, as well as an enlarged vertical tail fin. Service trials conducted with the modified flying-boats showed acceptable water performance, still not as good as that of the H6K, but they demonstrated such marked improvement in flight characteristics that the navy had no hesitation in ordering the type into production in late 1941 under the designation Navy Type 2 Flying Boat, which acquired subsequently the Allied codename 'Emily'. The type remained in operational use until the end of the war, by which time construction of all versions totalled 167.

The initial H8K1 production version (16 built), which was the same as the second and third prototypes, was soon superseded by the major series version, the H8K2 (112 built) which introduced more powerful Mitsubishi MK4Q engines. a revised tail unit, more extensive armament and ASV radar. After being used for service trials, the original H8K1 prototype was given Mitsubishi MK4Q engines and converted for use in a transport role, then being redesignated H8K1-L; it was later developed as a production transport accommodating 29 to 64 passengers according to role, being powered by the MK4Q engines and having armament reduced to one 20-mm cannon and one 13-mm (0.51-in) machine-gun. Ordered into production as the Navy Type 2 Transport Flying-Boat Seiku (clear sky), the variant was built to the extent of 36 aircraft. Two early production examples were used as development aircraft for an improved version with retractable wingtip floats and a retractable dorsal turret, being redesignated H8K3; they were later tested with 1,825-hp (1361-kW) Mitsubishi MK4T-B Kasei 25b engines under the changed designation H8K4, but no production aircraft were built.

Early production aircraft entered service in 1942, the type's operational debut being made on the night of 4-5 March 1942 when two aircraft based at Watje Atoll in the Marshall Islands, some 2,300 miles (3700 km) east of Pearl Harbor, were despatched to make a bombing attack on Oahu Island. This operation involved refuelling from a submarine at French Frigate Shoals, and it seemed unjust that such an ambitious piece of planning was frustrated by heavy cloud cover over the target area. Nevertheless, H8Ks proved highly effective, and the type was deployed on bombing, reconnaissance and transport missions, its heavy defensive armament making it a formidable adversary.

Variants

H8K1 Prototype
    One experimental prototype and two evaluation aircraft.
H8K1 (Navy Flying Boat type 2, Model 11)
    First operative model of series, 14 built.
H8K1-L
    Redesignation of the first prototype, after it was converted into a transport aircraft.
H8K2 (Model 12)
    Version with more powerful engines and major armament, equipped with search radar, 120 built.
H8K2-L Seiku ("Clear Sky"),(Model 32)
    Transport version of H8K1. Armed examples were equipped with two 20 mm Type 99 cannons and transport capacity of 29-64 passengers (36).
H8K3 (Model 22)
    Experimental version, H8K2 modified. Equipped with retractable floats in wingtips, sliding hatch side gun locations in place of the blisters, and a retractable dorsal turret all in an effort to increase speed, 2 prototypes.
H8K4 (Model 23)
    H8K3 with different engines, 2 converted.

Specifications (Kawanishi H8K2)

General characteristics

    * Crew: 10
    * Length: 28.15 m (92 ft 4 in)
    * Wingspan: 38.00 m (124 ft 8 in)
    * Height: 9.15 m (30 ft)
    * Wing area: 160 m² (1,721 ft²)
    * Empty weight: 18,380 kg (40,436 lb)
    * Loaded weight: 24,500 kg (53,900 lb)
    * Max takeoff weight: 32,500 kg (71,500 lb)
    * Powerplant: 4× Mitsubishi Kasei 22 radial engines, 1,380 kW (1,850 hp) each

Performance

    * Maximum speed: 465 km/h (290 mph)
    * Range: 7,150 km (4,440 mi)
    * Service ceiling: 8,760 m (28,740 ft)
    * Rate of climb: 8.1 m/s (1,600 ft/min)
    * Wing loading: 153 kg/m² (31 lb/ft²)
    * Power/mass: 0.22 kW/kg (0.14 hp/lb)

Armament

    * Guns:
          * 5 × 20 mm Type 99 cannon (one each in bow, dorsal, and tail turrets, plus one each in two waist blisters)
          * 5 × 7.7 mm (.303 in) Type 97 machine guns in fuselage hatches
    * Bombs: 2 × 800 kg (1,764 lb) torpedoes or 1,000 kg (2,205 lb) of bombs or depth charges

Avionics

    * Radar: Type 3 Mark 6 Model 4 (Type H6)

Aichi E13A

Numerically the most important of all Japanese float seaplanes during World War II, the Aichi E13A monoplane (of which 1,418 were produced) originated in a naval staff specification issued to Aichi, Kawanishi and Nakajima in 1937 for a three-seat reconnaissance seaplane to replace the six-year-old Kawanishi E7K2 float biplane. A prototype was completed late in 1938 and after competitive trials with the Kawanishi E13K in December 1940 was ordered into production as the Navy Type 0 Reconnaissance Seaplane Model 1. Early aircraft were embarked in Japanese cruisers and seaplane tenders the following year and, carrying a single 250kg bomb apiece, flew a series of raids on the Hankow-Canton railway. Soon afterwards E13A1 floatplanes accompanied the Japanese 8th Cruiser Division for reconnaissance patrols during the strike against Pearl Harbor in December 1941.

Thereafter, as production switched to Kyushu Hikoki KK at Zasshonokuma and accelerated, the seaplanes (codenamed 'Jake' by the Allies) were embarked in the battleships and cruisers of the Kantais (fleets), including the battleship Haruna and cruisers Chikuma and Tone of Vice Admiral Nagumo's Carrier Striking Force at the Battle of Midway. Because of mechanical problems with the ships' catapults there were delays in launching one of the four E13Als to search for the American carriers at dawn on the crucial 4 June 1942, depriving the Japanese of the vital initiative during the early stages of the assault on Midway. Furthermore the Chikuma's E13A1 was forced to return early when it suffered engine trouble, further reducing the all-important search area. One of the other 'Jake' pilots, from the cruiser Tone, eventually sighted the American fleet but at first failed to report the presence of carriers, causing a further 30-minute delay in arming the strike aircraft awaiting orders to launch from Japanese carriers. As it was, when the Americans launched their first strike, the pilots found the decks of the carriers Akagi, Kaga, Soryu and Hiryu clogged with aircraft which should have been attacking the American fleet.

In all, it is estimated that by mid-1943 more than 250 E13A1s were at sea aboard Japanese ships, though their use was severely curtailed whenever American fighters were in evidence. Nevertheless they continued to serve right up to the end of the war, many of them being ultimately used in suicide attacks on the huge American invasion fleets closing on the Japanese homeland.

H8K 'Emily'

The Kawanishi H8K flying boat (Allied code name "Emily") was an all-metal, four-engine, large-size, Type 2 Flying Boat used by the Imperial Japanese Navy and was considered to be the best flying boat of World War II. It was built to replace the Kawanishi H6K and to exceed the performance of the Short S.25 Sunderland and Sikorsky XPBS-1 Patrol Bomber. The Navy specification 13-Shi called for a top speed of 276 mph (444 km/h), a cruising speed of 207 mph (333 km/h) and a maximum range of 5,180 miles (8,336 km). It was ordered in 1938 the same time its predecessor, the Kawanishi H6K, went into service. A total of 167 of the type were built and it made its inaugural flight in January, 1941.

    The H8K had good performance, impressive speed and range, and was well armed and provided armor protection for the crew. Its offensive capability was very effective in anti-submarine campaigns and was the scourge of American submarines during the war.

    The cockpit sat high just forward of a cantilever wing and was powered by was powered by four 1,530 hp (1,140 kW) Mitsubishi MK4A Kasei 11 engines. The later version, the H8K2, was powered by four 1,850 hp (1,380 kW) Mitsubishi MK4Q Kasei 22 engines with water injection driving four-blade propellers.

    It had eight small unprotected fuel tanks in the wings and six large, partially self-sealing, fuel tanks in the hull. It used a Co2 inert gas system for fuel tank fire protection and had a unique feature that if a hull fuel tank was pierced, the fuel would drain into the bilge and could be pumped back into the undamaged tanks. The fuel capacity was 4,500 gallons (17,040 liters).

 The prototype was heavily armed with three 7.7 mm machine guns in the ventral position and each side-hatch. Five 20 mm cannons were provided in the nose, tail, dorsal and waist blisters. Armament on the H8K1 was reduced to two 20 mm cannons in the dorsal and tail turrets and four flexible 7.7 mm machine guns and carried two 800 kg (1,764 lb) torpedoes or sixteen 60 kg (132 lb) bombs or depth charges. The H8K2 carried the same armament as the H8K1 plus two additional 7.7 mm machine guns in either side of the cockpit. Most late production aircraft utilized a Mark VI Air to Surface Vessel radar system for submarine detection and served with first-line units. It was also heavily armored and was considered to be the most difficult Japanese aircraft to shoot down.

    The H8K was involved in a second raid on Pearl Harbor on March 4-5, 1942 and this was the longest distance ever undertaken by a two-plane bombing mission, and the longest bombing sortie ever planned without fighter escort. Two airplanes left Wotje Atoll in the Marshall Islands and were refueled by submarine at the French Frigate Shoals. However due to cloud cover, the raid did not accomplish any significant damage and there were no American casualties. Another long distance mission had been planned for Midway, but was cancelled after the refueling submarine discovered that the French Frigate Shoals were occupied by American Forces.

    The H8K was used on a wide range of patrol, reconnaissance, bombing, and transport missions throughout the Pacific war. As a troop carrier, it could hold up to 64 soldiers. Only four aircraft survived to the end of the war.

Mitsubishi Ki-46

The Mitsubishi Ki-15, which entered service in 1937, confirmed very quickly the value of high-speed reconnaissance aircraft. Used operationally in the Sino-Japanese conflict, it provided the Imperial Japanese Army with invaluable intelligence of enemy concentrations and movements. Impressed by the capability of the Ki-15, and considering its requirements when the moment came for the expansion of the Japanese empire, the army drew up the specification of a higher performance long-range aircraft of this category. This would be essential considering the vast area over which operations might develop, and early and accurate knowledge of enemy countermoves would be vital if quick and effective response was to be made.

At the end of 1937 Mitsubishi received the army's specification, which made speed and range paramount to any other consideration, leaving the company free to adopt any configuration/powerplant combination that would achieve the desired performance. The resulting aircraft, first flown in prototype form in late November 1939, was a cantilever low-wing monoplane, its thin-section wings incorporating considerable dihedral. A slender fuselage mounted a conventional tail unit, landing gear was of retractable tailwheel type and power was provided by two 900-hp (671-kW) Mitsubishi Ha-26-I radial engines which were wing-mounted in very clean nacelles. In fact, considerable efforts had been made to keep drag to a minimum and the Mitsubishi Ki-46, as the type was designated, was undoubtedly one of the best-looking aircraft of World War II.

Flight testing went well, but a maximum speed some 10 per cent below that specified caused some concern. However, as the Ki-46 was faster than the most recent army and navy fighters to enter service, it was ordered into production under the official designation Army Type 100 Command Reconnaissance Plane Model 1, this version being identified by Mitsubishi as theKi-46I. Early production aircraft, which began to enter service in early 1940, were found to have a number of teething problems. While these took considerable time to rectify, at no time was production status in doubt and the development of an improved Ki-46-II was soon under way. This introduced the 1,080-hp (805-kW) Mitsubishi Ha-102 engine with two-stage supercharger, and when tested in early 1941 this new version was found just able to exceed the originally specified maximum speed of 373 mph (600 km/h). Production Ki46- IIs were delivered to operational units as quickly as production would allow, and by the beginning of the Pacific war units with small numbers of these aircraft were dispersed throughout the entire area of intended operations.

Initially the high speed of the Ki-46-IIs at their optimum altitude made them immune from interception by Allied fighters, which were then operating without the benefits of ground control radar. However, as soon as US and British forces re-established themselves and began to introduce new-generation fighters, Ki-46-II losses began to mount rapidly. Such a situation had been foreseen by the army, and by the time that it arose the Ki-46-III with more powerful Mitsubishi Ha-112-II engines was almost ready to enter service. This new reconnaissance aircraft, which supplemented rather than replaced the Ki-46-IIs, was to be virtually free from interception until the closing stages of the Pacific war. In fact, its performance was such that a fighter interceptor version was produced in small numbers under the designation Ki-46-III KAI, these being conversions from standard Ki-46-III production aircraft. They carried an armament of two nose-mounted 20mm cannon plus an obliquely-mounted 37-mm cannon in the upper fuselage, but they were not particularly successful and not many conversions were made. A small number of ground-attack aircraft was also produced by conversions of Ki-46-IIIs and these, designated Ki-46-IIIb, were armed with only nose-mounted 20-mm cannon. An improved Ki-46-IV was planned in both reconnaissance and fighter versions, but did not progress beyond the prototype stage by the war's end. Allocated the Allied codename 'Dinah', the Ki-46 was in service from the beginning to end of the Pacific war, and its significance to the Japanese army can be judged by a production total no smaller than 1,742 of all versions.
Variants
(note:- The Shiki designations must be used in full, as written below, because the Type number only refers to the year of the designs inception.)
Army Type 100 Command Reconnaissance Plane
    The Shiki designation for the Ki-46 Command Reconnaissance Plane
Army Type 100 Air Defence Fighter
    The Shiki designation for the Ki-46 Interceptor Fighter
Army Type 100 Assault Plane
    The Shiki designation for the Ki-46 Assault Plane
Ki-46
    Prototype.
Ki-46 I
    Reconnaissance version of the Ki-46.
Ki-46 II
    The first operational model of the series.
Ki-46 II KAI
    Three-seat training version of the Ki-46. Used for radio and navigation training, with a redesigned cabin, dorsal echeloned extension. Conversions of the Ki-46 II.
Ki-46 III
Ki-46 III-KAI
    Defense interceptor/night fighter version of the Ki-46. Equipped with two 20 mm cannons in the nose and one 37 mm (1.46 in) cannon in the "Schräge Musik"-style dorsal frontal position.
Ki-46 III
    Land strike version of the Ki-46, without 37 mm (1.46 in) cannon armament.
Ki-46 IIIb
    Ground-attack version.
Ki-46 IIIc
    Not built design project.
Ki-46 IV
    Prototype, equipped with two turbocharged 1,119 kW (1,500 hp) Mitsubishi Ha-112-II RU engines, and more gasoline store capacity.
Ki-46 IVa/b
    Series models of reconnaissance/fighter aircraft, Not built design projects

Specification
Mitsubishi Ki-46-III
Powerplant: two 1,500-hp (1119-kW) Mitsubishi Ha112-II 14-cylinder radial piston engines
Performance: maximum speed 391 mph (630 km/h) at 19,685 ft (6000 m); service ceiling 34,450 ft (10500 m); range 2,485 miles (4000 km)
Weights: empty 8,444 Ib (3,830 kg); maximum takeoff 14,330 lb (6500 kg)
Dimensions: span 48 ft 2 3/4 in (14.70 m); length 36 ft 1 in (11.00 m); height 12 ft 8 3/4 in (3.88 m); wing area 344.46 sq ft (32.00 m2)
Armament: none, but some Ki-46-I and Ki-46-II aircraft carried a single 7.7-mm (0.303-in) Type 89 machine-gun on a trainable mount in the rear cockpit
Operators: Japanese Army, plus a small number used by the Japanese Navy

LINK

Mitsubishi Ki-15

The Ki-15-I was almost immediately placed into operational service at the beginning of the war with China in 1937. The aircraft proved useful in the early period of the Second Sino-Japanese War and performed missions deep into Chinese strategic rear areas, as far as reaching Lanzhou. Its high speed gave it a distinct advantage until the Chinese Air Force acquired Soviet Polikarpov I-16 fighters. This aircraft was used for level bombing, close support and photo reconnaissance before being eventually replaced by the Mitsubishi Ki-30.

Plans were already in hand to improve the Ki-15-I, and in September 1939 the Ki-15-II was put into production with the 671 kW (900 hp) Mitsubishi Ha-26-1; the smaller diameter of this both reduced drag and overcame one of the major shortcomings of the initial version: poor forward field of view past the large-diameter of the initial Nakajima Kotobuki engine. The improved version entered production in September 1939 as the Ki-15-II.

The Japanese Navy, impressed by the performance of this aircraft, ordered 20 examples of the Ki-15-II under the designation “Navy Type 98 Reconnaissance Plane Model 1," or Mitsubishi designation C5M1, even before the Army. The Navy acquired subsequently 30 C5M2 aircraft which had an even more powerful 708 kW (949 hp) Nakajima Sakae 12 engine. They were used for reconnaissance duties. In a subsequent upgrade, the army also experimented with an even more powerful engine with 783 kW (1,050 hp) Mitsubishi 102 radial in the Ki-15-III which did not enter production.

When production ended, approximately 500 examples of all versions of the Ki-15 had been built, the majority in front-line service when the Pacific War began. By 1943, the Ki-15 had been relegated to second-line roles, but numbers were expended in kamikaze attacks in the closing stages of World War II.

Variants
    Karigane I : Prototype version for civilian use
    Ki-15-I (Army Type 97 Command Reconnaissance Plane Model 1) : Initial production variant for the Japanese Army, with Nakajima Ha-8 (Army Type 94) 640 hp at take-off, 900 hp at 11,810 ft (3,600 m)
    Ki-15-II (Army Type 97 Command Reconnaissance Plane Model 2) : Improved Army production version with smaller, more powerful engine 14-cilinder Mitsubishi Ha-25-I (Army Type 99 Model 1) , with 850 hp at take-off, 900 hp at 11,810 ft. This gave an increased maximum speed of 317 mph at 14,205 ft (510 km/h at 4,300 m), roughly comparable with fighters like Hawker Hurricane or the Nakajima Ki-43 Hayabusa. The climb was even more improved: 16,405 ft (5,000 m) in 6 min 49 sec (6,83 min). This was archived despite the increase in weight (empty, normal, max: 3,510 vs 3,084 lb, normal 4,826 vs 4,482 and max 5,470 vs 5,071 lb). Maiden flight in June 1938, production started in September 1939[5]
    Ki-15-III  : Proposed upgraded version, did not enter production version. It had the Mitsubishi Ha-102 engine (1,080 hp at take-off, 1,055 hp at 9,185 ft and 950 hp at 19,030 ft), with a top speed of 329 mph (530 km/h), rougly the same of Ki-46 Dinah. But this latter was expected to be far better in other ways (endurance, two engine, etc), so this version never went in production, even if it was proposed since 1939
    C5M1 (Navy Type 98 Reconnaissance Plane Model I) : Improved version of Ki-15-I for the Japanese Navy
    C5M2 (Navy Type 98 Reconnaissance Plane Model 2) : Upgraded version of C5M1 with more powerful engine for the Japanese Navy

Mitsubishi Ki-15

The Ki-15-I was almost immediately placed into operational service at the beginning of the war with China in 1937. The aircraft proved useful in the early period of the Second Sino-Japanese War and performed missions deep into Chinese strategic rear areas, as far as reaching Lanzhou. Its high speed gave it a distinct advantage until the Chinese Air Force acquired Soviet Polikarpov I-16 fighters. This aircraft was used for level bombing, close support and photo reconnaissance before being eventually replaced by the Mitsubishi Ki-30.

Plans were already in hand to improve the Ki-15-I, and in September 1939 the Ki-15-II was put into production with the 671 kW (900 hp) Mitsubishi Ha-26-1; the smaller diameter of this both reduced drag and overcame one of the major shortcomings of the initial version: poor forward field of view past the large-diameter of the initial Nakajima Kotobuki engine. The improved version entered production in September 1939 as the Ki-15-II.

The Japanese Navy, impressed by the performance of this aircraft, ordered 20 examples of the Ki-15-II under the designation “Navy Type 98 Reconnaissance Plane Model 1," or Mitsubishi designation C5M1, even before the Army. The Navy acquired subsequently 30 C5M2 aircraft which had an even more powerful 708 kW (949 hp) Nakajima Sakae 12 engine. They were used for reconnaissance duties. In a subsequent upgrade, the army also experimented with an even more powerful engine with 783 kW (1,050 hp) Mitsubishi 102 radial in the Ki-15-III which did not enter production.

When production ended, approximately 500 examples of all versions of the Ki-15 had been built, the majority in front-line service when the Pacific War began. By 1943, the Ki-15 had been relegated to second-line roles, but numbers were expended in kamikaze attacks in the closing stages of World War II.

Variants
    Karigane I : Prototype version for civilian use
    Ki-15-I (Army Type 97 Command Reconnaissance Plane Model 1) : Initial production variant for the Japanese Army, with Nakajima Ha-8 (Army Type 94) 640 hp at take-off, 900 hp at 11,810 ft (3,600 m)
    Ki-15-II (Army Type 97 Command Reconnaissance Plane Model 2) : Improved Army production version with smaller, more powerful engine 14-cilinder Mitsubishi Ha-25-I (Army Type 99 Model 1) , with 850 hp at take-off, 900 hp at 11,810 ft. This gave an increased maximum speed of 317 mph at 14,205 ft (510 km/h at 4,300 m), roughly comparable with fighters like Hawker Hurricane or the Nakajima Ki-43 Hayabusa. The climb was even more improved: 16,405 ft (5,000 m) in 6 min 49 sec (6,83 min). This was archived despite the increase in weight (empty, normal, max: 3,510 vs 3,084 lb, normal 4,826 vs 4,482 and max 5,470 vs 5,071 lb). Maiden flight in June 1938, production started in September 1939[5]
    Ki-15-III  : Proposed upgraded version, did not enter production version. It had the Mitsubishi Ha-102 engine (1,080 hp at take-off, 1,055 hp at 9,185 ft and 950 hp at 19,030 ft), with a top speed of 329 mph (530 km/h), rougly the same of Ki-46 Dinah. But this latter was expected to be far better in other ways (endurance, two engine, etc), so this version never went in production, even if it was proposed since 1939
    C5M1 (Navy Type 98 Reconnaissance Plane Model I) : Improved version of Ki-15-I for the Japanese Navy
    C5M2 (Navy Type 98 Reconnaissance Plane Model 2) : Upgraded version of C5M1 with more powerful engine for the Japanese Navy

Kawanishi E7K

In March 1932 Aichi and Kawanishi began the competitive design of a new three-seat long-range reconnaissance f1oatplane. This was required by the Imperial Japanese Navy air force as a replacement for the Navy Type 90-3 Reconnaissance Seaplane which, built as the Kawanishi E5K, had proved to be disappointing in service use. A fabric-covered equal-span single-bay biplane of conventional design and construction, the Kawanishi E7K1 was carried on large strut-mounted twin floats, accommodated a crew of three in tandem open cockpits, and was powered by a 620-hp (462-kW) Hiro Type 91 'arrow' engine. First flown on 6 February 1933, the prototype passed its manufacturer's tests satisfactorily and in late May 1933 was handed over to the Japanese navy for service trials in competition with the AB-6 developed by Aichi to meet the same requirement. Navy evaluation left little doubt that Kawanishi's new floatplane was the better of the two, but no production order was forthcoming until after the receipt of a second prototype in late 1933. Some six months later, during May 1934, the E7K1 was ordered into production and given the designation Navy Type 94 Reconnaissance Seaplane. When it began to enter service in early 1935, the E7K1 very soon gained a good reputation for ease of handling, both on the water and in the air, but performance of the Hiro engine, derived from a French Lorraine powerplant, was disappointing. As a result, late production aircraft had a more powerful (750hp/ 559-kW) version of the Hiro Type 91 installed, but this proved no more reliable and with E7K1 production then totalling 183 (57 built by Nippon) Kawanishi began to look at alternatives.

During 1938 the company built a prototype E7K2 which was generally similar to the earlier production aircraft, but with the unreliable Hiro engine replaced by a Mitsubishi Zuisei (holy star) 11 radial engine. Flown for the first time during August 1938, this was ordered into production by the navy some three months later under the designation Navy Type 94 Reconnaissance Seaplane Model 2; at the same time the E7K1 version was retrospectively redesignated as the Navy Type 94 Reconnaissance Seaplane Model 1. Production of the E7K2 totalled about 350 aircraft, some 60 built by Nippon, and the E7K as a type saw extensive use for both beach- and ship-based operations from 1935 until the beginning of the Pacific war. By that time the E7K1s had been relegated to second-line duties, but the radial-engined higher-performance (some 23 mph/37 km/h faster) E7K2s remained in first-line roles until early 1943. These included antisubmarine patrol and inshore convoy escort, tasks for which they had never been intended, and many were still in use in liaison and training roles when the war ended. One more job remained, for like many obsolete types the E7Ks were pressed into service during the late stages of the war to take part in desperate kamikaze attacks. When, in the second half of 1942, codenames began to be allocated to Japanese aircraft to provide a simple and easily pronounceable means of referring to a type, the E7K2 became known as 'AIf', male Christian names being allocated to aircraft that were deployed basically as fighters or reconnaissance seaplanes.

Variants
E7K1
    Production version with a Hiro Type 91 engine, 183 built (including 57 built by Nippon Hikoki K.K.)
E7K2
    Re-engined version with a Mitsubishi Zuisei 11 radial engine, about 350 built (including 60 built by Nippon Hikoki K.K.)

Specifications (E7K2)
General characteristics
    Crew: 3
    Length: 34 ft 5½ in (10.50 m)
    Wingspan: 45 ft 11¼ in (14.00 m)
    Height: 15ft 10½ in (4.85 m)
    Wing area: 469.305 ft² (43.60 m²)
    Empty weight: 4,630 lb (2100 kg)
    Loaded weight: 7,275 lb (3300 kg)
    Powerplant: 1× Mitsubishi MK2 Zuisei 11 14 cylinder radial engine, 870 hp (649 kW)
Performance
    Maximum speed: 275 km/h (171 mph)
    Cruise speed: 100 kt at 1000 m (115 mph at 3,280 ft)
    Service ceiling: 7,060 m (23,165 ft)
    Wing loading: 15.5 lb/ft² (75.7 kg/m²)
Armament
    Guns: 1× fixed and 2× trainable 7.7mm (0.303in) Type 92 machine guns
    Bombs: 120 kg (265 lb) of bombs

Nagato-class On-board Aircraft

The Nagato class carried three observation planes launched by catapult forward of the "C" turret.

Mitsubishi F1M
Under the designation Mitsubishi Ka-17 the company designed during 1935 a two-seat aircraft to meet an Imperial Japanese Navy requirement for a catapult-launched short-range observation floatplane. A very clean equal-span single-bay biplane, the Ka-17 had a large central float and strut-mounted stabilising floats beneath the lower wings, adjacent to the wingtips. The fuselage accommodated the crew of two in tandem open cockpits, the pilot seated forward beneath a large cut-out in the trailing edge of the upper wing. Powerplant of the first prototype, flown during June 1936, was an 820-hp (611-kW) Nakajima Hikari (splendour) 1 radial engine, but early tests showed that performance on the water left much to be desired. After four F1M1 prototypes had been completed a number of changes were introduced to eradicate the shortcomings revealed in flight testing, including redesigned wings and increased vertical tail surface area, plus installation of the more powerful Mitsubishi Zuisei (holy star) 13 radial engine. Subsequent company testing showed that the remedial action had been successful, and service trials led to the type being ordered into production as the Navy Type 0 Observation Seaplane Model 11, Mitsubishi designation F1M2. A total of 1,118 was built by Mitsubishi (528) and the Sasebo Naval Air Arsenal (590), and in addition to the standard production aircraft, a small number was converted to serve as two-seat trainers under the designation F1M2-K. Allocated the Allied codename 'Pete', and used extensively from both ships and shore bases, because of their excellent performance F1M2s found employment in the unexpected roles of fighter and dive-bomber, as well as their intended use for coastal patrol, convoy escort and reconnaissance. In addition to those delivered to the Japanese navy, a small number was supplied to Thailand for use on coastal patrol duties.

Kawanishi E7K2
During 1938 the company built a prototype E7K2 which was generally similar to the earlier production aircraft, but with the unreliable Hiro engine replaced by a Mitsubishi Zuisei (holy star) 11 radial engine. Flown for the first time during August 1938, this was ordered into production by the navy some three months later under the designation Navy Type 94 Reconnaissance Seaplane Model 2; at the same time the E7K1 version was retrospectively redesignated as the Navy Type 94 Reconnaissance Seaplane Model l. Production of the E7K2 totalled about 350 aircraft, some 60 built by Nippon, and the E7K as a type saw extensive use for both beach- and ship-based operations from 1935 until the beginning of the Pacific war. By that time the E7K1s had been relegated to second-line duties, but the radial engined higher-performance (some 23 mph/37 km/h faster) E7K2s remained in first-line roles until early 1943. These included antisubmarine patrol and inshore convoy escort, tasks for which they had never been intended, and many were still in use in liaison and training roles when the war ended. One more job remained, for like many obsolete types the E7Ks were pressed into service during the late stages of the war to take part in desperate kamikaze attacks. When, in the second half of 1942, codenames began to be allocated to Japanese aircraft to provide a simple and easily pronounceable means of referring to a type, the E7K2 became known as 'AIf', male Christian names being allocated to aircraft that were deployed basically as fighters or reconnaissance seaplanes.

Nakajima E4N
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 floats 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.

Mitsubishi Ki 46 Profiles

The beautiful Ki 46 was the among the most capable reconnaissance aircraft of World War II. It performed critical intelligence work prior to the outbreak of hostilities by mapping invasion routes and Allied defenses.

Commencing in 1937, the Japanese army employed the Mitsubishi Ki 15 in China for reconnaissance purposes. This single-engine craft did extremely useful photographic work, although war planners realized a more modern airplane would be needed for a war with Western powers. Therefore, that same year they authorized Mitsubishi to commence research on a new twin-engine replacement for the Ki 15, with speed, altitude, and range taking precedence over all other considerations. A design team headed by Tomio Kubo then originated a prototype that first flew in November 1939. This new machine, the Ki 46, was startlingly beautiful to behold. It was a low-wing, all-metal affair with extremely rakish lines, a sharply pointed nose, and cleanly cowled engines. Test flights revealed it fell about 10 percent short of required performance, but it was still faster than any Japanese fighter in service. The following year more powerful motors were installed, and the Ki 46 easily reached 35,000 feet at 350 miles per hour, with endurance of seven hours. When the Ki 46 entered production in 1941, it was the most outstanding reconnaissance craft in the world. During World War II it received the Allied designation Dinah.

Prior to the Pacific war, the Dinah flew clandestine intelligence missions throughout Southeast Asia and the Pacific, carefully photographing Allied installations and the best invasion routes to reach them. It continued this work well into 1942, being so fast and high-flying that interception was virtually impossible. Eventually, improved Allied fighters began to take a toll on the earlier machines, so a new variant, the Ki 46 III, was introduced. It featured a front canopy that was completely fared into the fuselage. This model flew so high and fast that a special bomber-interceptor version was introduced late in 1944. Dinahs continued excellent reconnaissance work up through the end of hostilities. It was a truly outstanding aircraft for its time.