Experimental 7-Shi Carrier Attack Aircraft (Nakajima B4N1, Y3B)

In April 1932, the Navy issued instructions to Mitsubishi and Nakajima to prototype a new carrier-based attack aircraft to replace the unpopular Type 89 Carrier Attacker. Nakajima, with Engineer Yoshida Takao as chief designer, developed the distinctive biplane Y3B equipped with the newly designed “Hikari” 73O engine. Two prototypes were built in 1933 and submitted for Navy evaluation. This aircraft featured a Gal-type upper wing and an inverted Gal-type lower wing, with the central section crossing in an X-shape relative to the slender fuselage. Furthermore, the landing gear struts were cantilevered from the lower wing's bend, representing an extremely bold structural design. The fuel tanks were exposed and removable, mounted on both sides of the fuselage, similar to those on the Nakajima E4N2 Reconnaissance Seaplane and the Nakajima A2N Carrier Fighter Model 2. At the time, the development of tri-seat carrier-based attack aircraft was a major challenge not only for Mitsubishi and Nakajima but also for Aichi and the Naval Technical Arsenal. Particularly, the selection of a reliable, high-horsepower engine proved difficult, preventing the establishment of a definitive design. Two prototypes were built in 1933 with the short designation B4N1*, and delivered to the Navy for evaluation but they failed to win Navy approval. Mitsubishi submitted its 7-Shi Carrier Attack Aircraft but it crashed on takeoff due to engine failure. Because of these failings, the Navy began with a new design competition for a 9- Shi Carrier Attack Aircraft.

Check this amazing scratch-built model here.

General characteristics
Crew: 3 (pilot, navigator/bomb aimer and gunner)
Length: 10 m (32 ft 10 in)
Wingspan: 14 m (45 ft 11 in)
Height: 3.80 m (12 ft 6 in)
Wing area: 50.0 m2 (538 sq ft)
Empty weight: 2,000 kg (4,409 lb)
Gross weight: 3,800 kg (8,378 lb)
Powerplant: 1 × Nakajima Hikari 2 9-cylinder radial engine, 520 kW (700 hp)
Propellers: 3-bladed

Performance
Maximum speed: 220 km/h (140 mph, 120 kn)
Stall speed: 93 km/h (58 mph, 50 kn)
Endurance: 6 hr
Service ceiling: 5,500 m (18,000 ft)
Time to altitude: 12 minutes to 3,000 m (9,800 ft)
Armament
Guns: 1 × flexibly mounted 7.7 mm machine gun
Bombs: 1 × 800 kg (1,760 lb) torpedo, or 1 × 800 kg bomb, or 2 × 250 kg bombs

*Francillon, Model Art #327 and others mention that the designation was "B4N1", only Mikesh-Abe mention that it was "B3N1". Considering that the Mitsubishi entry in the 7-Shi competition was designated B4M1 agreed by everyone including Mikesh-Abe and that the officially adopted type was the B4Y1 (also agreed by everyone), it is safe to conclude that the "B3N1" designation mentioned in the Mikesh-Abe book was a missprint. The Wiki entry needs correcting...

Nakajima Bulldog Fighter

Nakajima's design for a parasol-wing fighter, along with those of other companies competing for the Army's requirement for a new fighter, met with early uncertainties. Eventually, Nakajima's design was further developed and became the successful Army Type 91 Fighter, but in the interim, Nakajima, in 1930, bought the licence-manufacturing rights for the Bristol Bulldog. This aircraft was thought by Nakajima to be an ideal replacement for the ageing Type Ko 4 Fighters. Like the earlier N-35 Reconnaissance Aircraft, this project was supervised by the same French team headed by Andre Marie, assisted by Maxime Robin and others. Because this was a British-designed aircraft, Leslie G. Frise of the Bristol Aeroplane Co and his assistant H.W. Dunn were invited to Japan to assist. The first prototype was completed in June 1930, followed soon after by the second prototype. The design was based upon the Bristol Bulldog Mk. II, but differed by having each engine cylinder covered by separate fairings, the interplane struts were changed to the N type as used on the Bristol Bullpup, and struts were used to brace the tailplane. The Nakajima Jupiter engine was substituted for the Bristol-built Jupiter. After two prototypes were built, some of the parts were found to have insufficient strength for safe flight, therefore Nakajima Chikuhei grounded them. As a consequence, they were never submitted to the Army for evaluation; however, Nakajima's design for the parasol-wing Type 91 Fighter had by now achieved success. The two Bulldogs were eventually donated to the Navy, at the outbreak of the Shanghai Incident, for structural research purposes.

General characteristics

Single-engine single-seat fighter biplane. Metal structure with fabric covering.

Crew: Pilot in open cockpit.

Length: 7.54m (24ft 9in)

Span: 10.36m (34ft)

Height: 2.99m (9ft 91/2in)

Wing area: 28.5sq m (306.781sq ft)

Wing loading 56.1kg/sq m (11.51b/sq ft)

Power loading 3.55kg/hp (7.81b/hp)

Empty weight: 1,000kg (2,2041b)

Gross weight: 1,600kg (3,5271b)

Powerplant: 450-520hp Nakajima Jupiter VII nine-cylinder air-cooled radial engine, driving a two-bladed wooden propeller.

Performance

Maximum speed: 148kt (170.3mph) at 3,000m (9,843ft)

Climb to 5,000m (16,404ft) in 11 min

Service ceiling: 7,650m (25,098ft)

Aichi B7A1 "Ryusei" (Grace) by Jan Voorbij

Aichi B7A1 "Ryusei" (Grace)

Dive bomber / Torpedobomber

Pre-production plane: 1 of 9 prototypes

Imperial Japanese Navy, Kougeki (attack) 5th Hikotai, 752nd Kokutai, April/May 1945 and later 1945 Katori Naval Air Base April 1945 till the end of May 1945, then moved to Kisarazu Naval Air base. Captured by US troops in August 1945.

Fujimi 7AF1, 1:72

- Jan Voorbij, Holand -

Kawasaki Experimental Carrier Reconnaissance Aircraft

In March 1927, the Navy decided to manufacture an experimental aircraft funded by a program sponsored by the Kaibo Gikai (Maritime Defense Volunteer Association), and named the project: 'Research of Material for All-metal Aircraft'. Kawasaki was awarded the project by the Navy. It was to be a single-engine carrier reconnaissance aircraft having an all-metal structure with fabric covering. It had a fully cantilever parasol wing with marked sweepback, and large area slotted flaps, the first in Japan and probably the first in the world. At that time, no monoplane existed for carrier-based aircraft and there were certainly none with cantilever wings and slotted flaps. The fuselage was unusual being almost triangular in the cross section. The structure of the aircraft was heavily influenced by Dornier design practices. 

Design begun in March 1927 and completed in June 1928 under the leadership of Junichiro Nagahata and his assistant Hiroshi Sato. Both engineers had been in charge of aircraft design at the Aviation Research Department, Naval Technical Research Institute. The aircraft was built at the Kawasaki Dockyard, with the construction being completed in September 1928. Flight tests began in March 1929 at Kasumigaura under the control of Navy Cdr Sakae Yamamoto. However, tests were suspended after very few flights because of problems with flap operation. The flaps were considered to be a major feature of this aircraft and their use at such an early date deserves to be recorded in aeronautical engineering history. But early suspension of the tests without further refinements to the flaps, coupled with top-secret security, resulted in the lack of public awareness and has deprived this design of its rightful place in history. With this aircraft Kawasaki's affiliation with the Japanese Navy ended, and the company became solely a manufacturer of Army aircraft and a few civil types.

General characteristics

Single-engine cantilever parasol-monoplane with slotted flap system. All-metal construction with fabric covering.

Crew: two in open cockpits

Length: 10.65m (34ft 111/2in)

Span: 16.60m (54ft 51/2in)

Height: 3.18m (10ft 51/4in)

Wing area: 43.70sq m (470.3 98sq ft)

Wing loading: 41.2kg/sq m (8.41b/sq ft)

Power loading: 4kg/hp (8.81b/hp)

Empty weight: 1,200kg (2,6451b)

Gross weight: 1,800kg (3,9681b)

Powerplant: 450-600hp Mitsubishi-Hispano-Suiza twelve-cylinder vee water-cooled engine, driving a two-bladed wooden propeller.

Performance

Maximum speed: 142kt (164mph) at sea level

Service ceiling: 10,000m (32,808ft)

Endurance 3 hours

Multi-view illustration from Encyclopedia Vol.4

Mitsubishi Type 10 Torpedo Bomber 1MT1

An 1MT1N belonging to the Kasumigaura Kokutai as indicated by the letter "R2 on its tail.

The Type 10 Torpedo Bomber (company code: 1MT1. The number ten refers to the 10th year of the reign of Emperor Taisho, i.e. 1921) was the third* aircraft designed by former Sopwith designer Engineer Herbert Smith in Japan and was Japan's first domestically produced torpedo bomber. The first prototype was completed at the Nagoya Factory on August 9, 1922. On the same day, it was test flown by pilot William Jordan and armed with a 908  lb dummy torpedo, it successfully completed its maiden flight of approximately 30 minutes at the factory airfield. Subsequently, the second prototype was completed, and further trials were conducted at Kasumigaura Airfield in November. 

It was a fixed-landing-gear, single-engine, single-seat aircraft with a wooden frame covered in fabric. The first prototype was fitted with a 450-horsepower Napier Lion engine (hence the letter N in the 1MT1N designation), while the second aircraft was equipped with a 370-horsepower Lorraine engine (indicated by the L in the 1MT1L designation).
The first model was approximately 7 kg heavier due to the engine's weight, but its greater power enabled a maximum speed 13.5 knots faster under light load (1,605 kg) and a climb time to 3,048 meters reduced by 4 minutes and 12 seconds. Consequently, the type equipped with the Napier Lion engine (1MT1N) entered production, with 10 aircraft manufactured in fiscal year 1922 and 10 in fiscal year 1923, totaling 20 units. 
This Type 10 Torpedo Bomber was characterized by its adoption of a triplane configuration and its single-seat design, which meant it possessed absolutely no defensive armament against enemy fighters or other threats. The triplane configuration had been employed during the First World War in aircraft such as the British Sopwith Triplane fighter and the German Fokker Dr I fighter. It offered advantages in terms of reducing airframe size, improving maneuverability, and increasing payload capacity. The 1MT was adopted precisely for these advantages. It surpassed the biplane Blackburn Swift carrier-based torpedo bomber and Sopwith Cuckoo carrier-based torpedo bomber in agility and maneuverability, while its speed and climb rate exceeded those of the Type 10 Carrier Reconnaissance Plane (Mitsubishi 2MR). However, the triplane configuration also presented the problem of increased overall height. In the case of the 1MT, when loaded onto the aircraft carrier Hosho, its height proved excessive, leaving insufficient clearance beneath the hangar ceiling and causing difficulties in handling within the ship. Being single-seat and lacking machine guns was a trait shared with the imported Swift and Cuckoo, but practical trials demonstrated the necessity for defensive armament. Consequently, development of its successor, the biplane, two-seat Model 13 Carrier-based Attack Aircraft (Mitsubishi B1M), commenced urgently and the 1MT disappeared from the list of aircraft in service in 1924. 
Among the three Type 10 models designed by Engineer Smith, this was the shortest-lived. However, during its service, LTJG Kikuchi Tomozo(?), an instructor at Kasumigaura Air School, successfully ascended to an altitude of 7,620 meters in an 1MT equipped with an oxygen inhalation apparatus on July 4, 1923. This surpassed the Japanese altitude record set five days earlier by LTJG Ohashi in a Type 10 carrier fighter. Furthermore, on December 5 of the same year, this aircraft achieved the first successful aerial launch test of the 18-inch (45cm) domestically produced torpedo. This torpedo, developed at the Yokosuka Naval Arsenal based on the Type 44 45cm naval torpedo, saw its prototype completed in 1921. Following over fifty launch trials conducted by LT Akashiba and LTJG Kikuchi using the Type 10 Torpedo Bomber, it was confirmed that both the diving and running performance were significantly superior to the existing 14-inch short torpedo, leading to its adoption as the Type 44 Aerial Torpedo. It remained in service until around 1934, when it was replaced by the Type 91 Aerial Torpedo, developed from the outset as an aerial torpedo. This torpedo was transitional in nature for an air-launched type, and the 1MT itself proved short-lived. Nevertheless, its contribution in paving the way for air-launched torpedo attacks, which later achieved numerous combat successes, cannot be forgotten.

General characteristics
Single-engine triplane carrier-borne torpedo carrier. Wooden structure with fabric covering. Non-folding wings.
Crew: One pilot in open cockpit
Length: 9.779m (32ft lin)
Wingspan: 13.259m (43ft 6in)
Height: 4.457m (14ft 71/2in)
Wing area: 43sq m (462.863sq ft)
Wing loading 36.1kg/sq m (7.31b/sq ft)
Power loading 5.56kg/hp (12.21b/hp)
Empty weight: 1,370kg (3,0201b)
Gross weight: 2,500 kg (5,511 lb)
Powerplant: 1 × Napier Lion , 336 kW (450 hp)

Performance
Maximum speed: 209 km/h (130 mph, 113 kn)
Cruising speed 130 km/h (81 mph, 70 kn)
Climb to 3,050m (10,000ft) in 13min 30sec
Service ceiling: 6,000 m (19,680 ft)
Endurance 2.3 hours

Armament
1 × 457 mm (18 in), 800 kg (1,764 lb) torpedo

*The other two aircraft were the Mitsubishi 1MF carrier fighter and the Mitsubishi 2MR carrier-based reconnaissance aircraft.

Artwork by Nohara Shigeru of a Kasumigaura Kokutai 1MT1N featured in Model Art #553.

A photo of an 1MT1 without a tail marking I spotted on the net. Is it undergoing trials? Could it be the 1MT1N prototype with pilot William Jordan climbing in the cockpit and the dummy torpedo hanging on the belly? Note the two smaller oppenings under the exhausts and the bigger one behind them mirroring the port side seen in the previous photo.

On the other hand in this photo from Wiki, the cowling openings are different. Could this be one of the 1MT1L aircraft with the Napier Lion engine?

One of the 1MTs was converted into a seaplane by Ando Aeroplane Research Studio at Shin-Maiko beach, Chita Peninsula, Aichi Prefecture, in 1926 and was used as a passenger transport and pilot trainer.

In the 2015 Modelling Show in Shizuoka, I spotted a fantastic 1MT1 built by Tanaka Yoshihiro of Stall. (Marusan 1/50 kit seen below)

Mitsubishi A5M "Claude" by Fabio Balzano

Here's another Mitsubishi A5M in 1/72, this time a Mk.4, obtained by modifying the less-than-perfect Hobby Boss A5M2b kit. The new shape of the windscreen is a home made vacuform.

This is a very worn aircraft from the Omura Kokutai, Omura Airbase, Nagasaki Prefecture, in August 1945.

I hope you like it!

Fabio Balzano - Italy

Mitsubishi MC-20 - video

A vintage video introducing the latest civilian transport aircraft; the Mitsubishi MC-20.

The name, MC, was inspired by the Douglas series of transports like the DC-2 and the DC-3 and it naturally meant"Mitsubishi Commercial".

It should be noted that as a name it was an one-off, i.e. there were no "MC-19" or "MC-22". The civilian version of he Mitsubishi Ki-21 "Sally" bomber is sometimes reffered to as "MC-21" but the Army was unwilling to adopt a civilian-based designation and opted, at least officially, for "M-21" instead. 

The Army version of the MC-20 was the Ki-57. More about the type, here.

Of particular interest is the overall look of the aircraft fresh out of the factory, with some parts painted gray and others seemed to be left unpainted.

Hanriot / Mitsubishi HD.14 Trainer - video

An extremely rare and surprisingly clear short clip features an Hanriot HD.14 Trainer, of which 145 were licence-built by Mitsubishi for the Imperial Japanese Army receiving the designation "Type Ki Trainer". Note the overall IJAAF "hairyokushoku" (gray green).