Mitsubishi G4M
Encyclopedia
The Mitsubishi
Mitsubishi
The Mitsubishi Group , Mitsubishi Group of Companies, or Mitsubishi Companies is a Japanese multinational conglomerate company that consists of a range of autonomous businesses which share the Mitsubishi brand, trademark and legacy...
G4M (or "Type 1 land-based attack aircraft")一式陸上攻撃機, 一式陸攻 Isshiki rikujō kōgeki ki, Isshikirikkō was the main twin-engine, land-based bomber used by the Imperial Japanese Navy Air Service
Imperial Japanese Navy Air Service
The Imperial Japanese Navy Air Service was the air arm of the Imperial Japanese Navy during World War II, the organization was responsible for the operation of naval aircraft and the conduct of aerial warfare in the Pacific War.It was controlled by the Navy Staff of the Imperial Japanese Navy and...
in World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
. The Allies gave the G4M the reporting name
World War II Allied names for Japanese aircraft
The World War II Allied names for Japanese aircraft were reporting names, often described as codenames, given by Allied personnel to Imperial Japanese aircraft during the Pacific campaign of World War II. The names were used by Allied personnel to identify Japanese aircraft for reporting and...
Betty. The Allies usually gave Japanese fighters and floatplane
Floatplane
A floatplane is a type of seaplane, with slender pontoons mounted under the fuselage; only the floats of a floatplane normally come into contact with water, with the fuselage remaining above water...
s male names, while giving female names to bombers and reconnaissance aircraft
Reconnaissance aircraft
A reconnaissance aircraft is a manned military aircraft designed, or adapted, to carry out aerial reconnaissance.-History:The majority of World War I aircraft were reconnaissance designs...
. These code names did not come into general use until mid-1943.
The G4M had a one-way range of about 3,700 miles which was achieved by its structural lightness and an almost total lack of protection for its crew, with no armor plating or self-sealing aviation fuel tanks
Self-sealing fuel tank
In aviation, self-sealing fuel tank is a fuel tank technology in wide use since World War II that prevents fuel tanks primarily on aircraft from leaking fuel and igniting after being damaged by enemy fire....
. These omissions proved to be its weakness when opposition from American fighter aircraft increased during the second half of the Pacific War
Pacific War
The Pacific War, also sometimes called the Asia-Pacific War refers broadly to the parts of World War II that took place in the Pacific Ocean, its islands, and in East Asia, then called the Far East...
of World War II.
Design and development
The G4M was designed for a long range and high speed at the time of its introduction. Consequently, several weight-saving measures were incorporated into the design, such as dispensing with self-sealing fuel tankSelf-sealing fuel tank
In aviation, self-sealing fuel tank is a fuel tank technology in wide use since World War II that prevents fuel tanks primarily on aircraft from leaking fuel and igniting after being damaged by enemy fire....
s, which caused Allied fighter pilots to give it derisive nicknames such as "the one-shot lighter", "the flying Zippo
Zippo
A Zippo lighter is a refillable, metal lighter manufactured by Zippo Manufacturing Company of Bradford, Pennsylvania, U.S. Thousands of different styles and designs have been made in the seven decades since their introduction including military ones for specific regiments.-Establishment:George G...
" and "the flying cigar" because of their tendency to explode or catch on fire from any slight damage to the fuel tank wings after being hit by aerial machine gun fire or ground antiaircraft fire. Similarly, pilots of 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...
despairingly called the G4M "Betty" the "Type One Lighter", "The Flying Lighter" of the "Hamaki" ("cigar"). This was partially due to the fact that on many occasions, the G4M was used for low-altitude torpedo attacks on shipping in which their performance advantages were negated, and the G4M was frequently shot down by antiaircraft artillery fire, and even by small arms. The "Betty"'s relatively large size made it an easy gunnery target, and the predictable approach path required for a torpedo run made for a generally easy interception by Allied fighter aircraft.
When used for medium to high-altitude bombing against stationary land targets like a supply depots, seaports, or airfields, "ease of interception" was another matter entirely. Using its long range and high speed, the G4M could appear from any direction, and then it could be gone before many fighters intercepted them. The 20 mm cannon in its tail turret was much heavier armament than was commonly carried by bombers of either side, making aerial attacks from the rear quite dangerous for the Allied fighter aircraft. Sometimes, assuming they did not catch fire in the first place after being hit in the wings by flak from the ground or machine gun bullets from enemy fighters, G4Ms also proved to be able to remain airborne despite being badly shot up. For example, after the attack of the 751 Kokutai attack on the USS Chicago
USS Chicago
Four United States Navy ships have been named Chicago, after the city of Chicago, Illinois.* The was a protected cruiser launched in 1885 and active in World War I; later converted to a seaplane tender, then a barracks ship, finally being renamed Alton in 1928 and lost at sea, while under tow in...
during the Battle of Rennell Island
Battle of Rennell Island
The Battle of Rennell Island took place on 29–30 January 1943, and was the last major naval engagement between the United States Navy and the Imperial Japanese Navy during the Guadalcanal campaign of World War II...
, three out of four survivors (out of 11 aircraft committed to the attack) returned flying on only one engine.
Towards the end of World War II (1945), the "Betty" bomber was commonly used for carrying and launching kamikaze
Kamikaze
The were suicide attacks by military aviators from the Empire of Japan against Allied naval vessels in the closing stages of the Pacific campaign of World War II, designed to destroy as many warships as possible....
aircraft, and was the usual aircraft for carrying the Ohka
Ohka
The Yokosuka MXY-7 Ohka was a purpose-built, rocket powered human-guided anti-shipping kamikaze attack plane employed by Japan towards the end of World War II...
kamikaze manned rocket-powered bombs.
Production
- G4M1 Model 11: 1172 examples (including prototypes.)
- G4M2 Models 22, 22 Ko and 22 Otsu: 429 examples.
- G4M2a, Models 24, 24 Ko, 24 Otsu, 24 Hei, and 24 Tei: 713 examples.
- G4M3 Models 34 Ko, 34 Otsu, and 34 Hei: 91 examples.
- G6M1: 30 examples.
- Total production of all versions: 2,435 examples.
Operational history
Junkers Ju 88
The Junkers Ju 88 was a World War II German Luftwaffe twin-engine, multi-role aircraft. Designed by Hugo Junkers' company through the services of two American aviation engineers in the mid-1930s, it suffered from a number of technical problems during the later stages of its development and early...
and Heinkel He 111
Heinkel He 111
The Heinkel He 111 was a German aircraft designed by Siegfried and Walter Günter in the early 1930s in violation of the Treaty of Versailles. Often described as a "Wolf in sheep's clothing", it masqueraded as a transport aircraft, but its purpose was to provide the Luftwaffe with a fast medium...
medium bombers, and also the American North American B-25 Mitchell and Martin B-26 Marauder bombers. These were all commonly used for antiship roles. The G4M Model 11 was prominent in attacks on Allied shipping in the 1941 to early 1944 time frame, but after that time, it was increasingly easy prey for Allied fighters.
The G4M's baptism by fire occurred on 13 September 1940 in Mainland China
Mainland China
Mainland China, the Chinese mainland or simply the mainland, is a geopolitical term that refers to the area under the jurisdiction of the People's Republic of China . According to the Taipei-based Mainland Affairs Council, the term excludes the PRC Special Administrative Regions of Hong Kong and...
, when 27 "Bettys" and Mitsubishi C5Ms of 1st Rengo Kokutai (a composite force including elements of the Kanoya and Kizarazu Kokutais (Air Groups)) departed from Taipei
Taipei
Taipei City is the capital of the Republic of China and the central city of the largest metropolitan area of Taiwan. Situated at the northern tip of the island, Taipei is located on the Tamsui River, and is about 25 km southwest of Keelung, its port on the Pacific Ocean...
, Omura, and Jeju City
Jeju City
Jeju is the capital of Jeju province in South Korea and the largest city on the island of Jeju. Its geographical location is . The city is served by Jeju International Airport ....
to attack Hankow. The bombers and reconnaissance aircraft were escorted by 13 A6M Zero
A6M Zero
The Mitsubishi A6M Zero was a long-range fighter aircraft operated by the Imperial Japanese Navy Air Service from 1940 to 1945. The A6M was designated as the , and also designated as the Mitsubishi A6M Rei-sen and Mitsubishi Navy 12-shi Carrier Fighter. The A6M was usually referred to by the...
s of 12st Kokutai led by the I.J.N. lieutenant
Lieutenant
A lieutenant is a junior commissioned officer in many nations' armed forces. Typically, the rank of lieutenant in naval usage, while still a junior officer rank, is senior to the army rank...
, Saburo Shindo. A similar operation occurred in May 1941. In December 1941, 107 G4Ms based on Formosa
Formosa
Formosa or Ilha Formosa is a Portuguese historical name for Taiwan , literally meaning, "Beautiful Island". The term may also refer to:-Places:* Formosa Strait, another name for the Taiwan Strait...
of 1st Kokutai and Kanoya Kokutai belonging to the 21st Koku Sentai (Air Flotilla) crossed the Luzon Strait
Luzon Strait
The Luzon Strait is the strait between the island country of Taiwan and Luzon island of the Philippines. The strait thereby connects the Philippine Sea to the South China Sea in the western Pacific Ocean....
en route to bombing the Philippines
Philippines
The Philippines , officially known as the Republic of the Philippines , is a country in Southeast Asia in the western Pacific Ocean. To its north across the Luzon Strait lies Taiwan. West across the South China Sea sits Vietnam...
, and this was the beginning to widespread invasion of the islands of the Southwest Pacific Theater.
Sinking of Prince of Wales and Repulse
The sinking of Prince of Wales and Repulse was a Second World War naval engagement that took place north of Singapore, off the east coast of Malaya, near Kuantan, Pahang where the British Royal Navy battleship HMS Prince of Wales and battlecruiser HMS Repulse were sunk by land-based bombers and...
off the eastern coast of British Malaya
British Malaya
British Malaya loosely described a set of states on the Malay Peninsula and the Island of Singapore that were brought under British control between the 18th and the 20th centuries...
on 10 December 1941. These carried out the attacks alongside the older Japanese bombers, the Mitsubishi G3M
Mitsubishi G3M
The Mitsubishi G3M was a Japanese bomber used during World War II.-Design and development:...
"Nells" which were doing high-level bombing runs. The battleship
Battleship
A battleship is a large armored warship with a main battery consisting of heavy caliber guns. Battleships were larger, better armed and armored than cruisers and destroyers. As the largest armed ships in a fleet, battleships were used to attain command of the sea and represented the apex of a...
Prince of Wales and the battlecruiser
Battlecruiser
Battlecruisers were large capital ships built in the first half of the 20th century. They were developed in the first decade of the century as the successor to the armoured cruiser, but their evolution was more closely linked to that of the dreadnought battleship...
Repulse were the first two capital ships ever to be sunk exclusively by air attack during a war, while on the open ocean. Those bomber crews were a handful of selected Imperial Japanese Naval Air Force (IJNAF) aviators in prewar Japan, who had skills not only in torpedo-attacks at an altitude of less than 30 ft (9 m), but also in being able to navigate long-range flight over the ocean to pinpoint naval targets moving quickly on the sea. This same squadrons in Kanoya Air Group of Kanoya Kokutai (751 Ku), Genzan Air Group of Genzan Kokutai (753 Ku), and the Mihoro Air Group of Mihoro Kokutai (701 Ku). These sank the British capital battle ships, and they later carried out an extended series of attacks against U.S. Navy and Allied ships, and on land targets during the six-month-long Battle of Guadalcanal (in the Solomon Islands
Solomon Islands
Solomon Islands is a sovereign state in Oceania, east of Papua New Guinea, consisting of nearly one thousand islands. It covers a land mass of . The capital, Honiara, is located on the island of Guadalcanal...
), in late 1942.
On 8 August 1942, the second day of the U.S. Marines landing on Guadalcanal, IJNAF's 23 G4M1s conducted a torpedo attack against American ships at Lunga point, Guadalcanal. A total of 18 of the attacking G4M1s were shot down, due to very heavy antiaircraft fire, and air cover from Grumman F4F Wildcat fighters based on three American aircraft carriers. In all, 18 Japanese crews – approximately 120 aviators– were missing at the beginning of the month. More than 100 Japanese G4M1s and their best crews (with no substitutes available) were shot down during the many following battles around Guadalcanal, from August through October 1942. In the two days of the Battle of Rennell Island
Battle of Rennell Island
The Battle of Rennell Island took place on 29–30 January 1943, and was the last major naval engagement between the United States Navy and the Imperial Japanese Navy during the Guadalcanal campaign of World War II...
on 29 and 30 January 1943, 10 out of 43 Japanese G4M1s were shot down during night torpedo attacks, all by the U.S. Navy's antiaircraft fire. About 70 Japanese aviators, including Lieutenant Commander
Lieutenant Commander
Lieutenant Commander is a commissioned officer rank in many navies. The rank is superior to a lieutenant and subordinate to a commander...
Higai, were killed during that battle.
T1-323
T1-323 was the tail number of the plane carrying Japanese Admiral Isoroku Yamamoto on an inspection tour throughout the South Pacific when he was shot down and killed by American fighter aircraft during World War II...
- which was carrying 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...
Admiral
Admiral
Admiral is the rank, or part of the name of the ranks, of the highest naval officers. It is usually considered a full admiral and above vice admiral and below admiral of the fleet . It is usually abbreviated to "Adm" or "ADM"...
Isoroku Yamamoto
Isoroku Yamamoto
was a Japanese Naval Marshal General and the commander-in-chief of the Combined Fleet during World War II, a graduate of the Imperial Japanese Naval Academy and a student of Harvard University ....
- was attacked and shot down by Lockheed P-38 Lightnings from 339th Fighter Squadron
339th Flight Test Squadron
The 339th Flight Test Squadron is a United States Air Force unit based at Robins AFB, Georgia. It is part of the Warner Robins Air Logistics Center, with a mission to certify aircraft as worthy to return to service...
of the 347th Fighter Group, Thirteenth Air Force
Thirteenth Air Force
The Thirteenth Air Force is a numbered air force of the United States Air Force Pacific Air Forces . It is headquartered at Hickam Air Force Base on the island of Oahu, Hawaii. 13 AF has never been stationed in the continental United States...
, USAAF
United States Army Air Forces
The United States Army Air Forces was the military aviation arm of the United States of America during and immediately after World War II, and the direct predecessor of the United States Air Force....
on 18 April 1943.
The G4M Model 11 was replaced by Models 22,22a/b,24a/b,25,26 and 27 after June 1943, following service in New Guinea
New Guinea
New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...
, the Solomons, and the South Pacific
Oceania
Oceania is a region centered on the islands of the tropical Pacific Ocean. Conceptions of what constitutes Oceania range from the coral atolls and volcanic islands of the South Pacific to the entire insular region between Asia and the Americas, including Australasia and the Malay Archipelago...
area, in defense of the Marianas and finally in Okinawa. Others had field modifications resulting in the Model 24j which carried suicide flying bombs Yokosuka MXY7 Ohka Model 11 beginning on 21 March 1945, with disastrous results due to extensive Allied fighter opposition.
From November 1944 to January 1945, G4Ms were one of the main types of aircraft used in the Japanese air attacks on the Mariana Islands
Japanese air attacks on the Mariana Islands
During World War II, a series of Japanese air attacks on the Mariana Islands took place between November 1944 and January 1945. These raids targeted United States Army Air Forces bases and sought to disrupt the bombing of Japan by B-29 Superfortress heavy bombers operating from the islands...
, and plans to use converted G4Ms to land commando
Commando
In English, the term commando means a specific kind of individual soldier or military unit. In contemporary usage, commando usually means elite light infantry and/or special operations forces units, specializing in amphibious landings, parachuting, rappelling and similar techniques, to conduct and...
s on the islands were developed in mid-1945 and only cancelled at the end of the war.
Following the loss of Okinawa, G4Ms constituted the main weapon of the land-based Japanese naval bomber force, consisting of 20 Kokutais at the end of the war, including the testing air group equipped in 1944–45 with the latest version G4M3 Model 34 and 36 which arrived too late to have an impact on the war.
As part of the negotiations for the surrender of Japan
Surrender of Japan
The surrender of Japan in 1945 brought hostilities of World War II to a close. By the end of July 1945, the Imperial Japanese Navy was incapable of conducting operations and an Allied invasion of Japan was imminent...
, two demilitarized G4Ms, given the call-signs Bataan 1 and Bataan 2
Bataan 1 and Bataan 2
Bataan 1 and Bataan 2 were two demilitarized Japanese Mitsubishi G4M "Betty" bomber/transport aircraft that carried the first surrender delegations from Japan to Ie Shima as part of the surrender of Japan in World War II...
were sent to Ie Shima
Iejima
Ie jima is an island in Okinawa Prefecture, Japan, lying a few kilometers off the Motobu Peninsula of Okinawa Honto, Okinawa Islands. It measures 20 km around and has a population of 5,055...
carrying the first surrender delegations as the first leg of their flight to Manila
Manila
Manila is the capital of the Philippines. It is one of the sixteen cities forming Metro Manila.Manila is located on the eastern shores of Manila Bay and is bordered by Navotas and Caloocan to the north, Quezon City to the northeast, San Juan and Mandaluyong to the east, Makati on the southeast,...
, the Philippines.
Versions
G4M1
G4M1 Prototypes: Japanese Navy land Based Bomber Type 1. Two prototypes built.G4M1 Model 11: Japanese Navy Land Attack Bomber Type 1. The first bomber model of series, with 1,140 kW (1,530 hp) Mitsubishi MK4A Kasei Model 11 engines driving three-blade propellers. Following modifications were made during the production:
- March 1942: The first aircraft (241st production example) fitted with MK4E Kasei Model 15 engines with larger superchargerSuperchargerA supercharger is an air compressor used for forced induction of an internal combustion engine.The greater mass flow-rate provides more oxygen to support combustion than would be available in a naturally aspirated engine, which allows more fuel to be burned and more work to be done per cycle,...
s for better high altitude performance, became standard in August 1942 from 406th aircraft onwards. These MK4E-engined aircraft have often (erroneously) been referred as the G4M1 Model 12. - Summer 1942: Propeller spinners introduced.
- March 1943: From 663rd machine onwards, 30 mm (1.18 in) rubber ply sheets installed beneath the wing outer surfaces to protect the undersides of the fuel tanks (speed reduced by 9 km/h/6 mph and range by 315 km/196 mi), 5 mm (.2 in) armour platesVehicle armourMilitary vehicles are commonly armoured to withstand the impact of shrapnel, bullets, missiles, or shells, protecting the personnel inside from enemy fire. Such vehicles include tanks, aircraft, and ships....
added into tail gunner's compartment. - Spring 1943: Outer half of the tail cone cut away in order to improve tail gunner's field of fire.
- August 1943: A completely redesigned tail cone, with reduced framing and wide V-shaped cut out; this form of tail cone was also used in all G4M2 models.
- September 1943: Individual exhaust stacks from 954th airframe onwards.
Production of the G4M1 ended in January 1944.
G4M2
The first of the four G4M2 prototypes flew in December 1942. It differed from the preceding model in having MK4P Kasei Model 21 engines with VDM Electric four-blade propellers capable of full feathering function, redesigned main wings with LB type laminar flowLaminar flow
Laminar flow, sometimes known as streamline flow, occurs when a fluid flows in parallel layers, with no disruption between the layers. At low velocities the fluid tends to flow without lateral mixing, and adjacent layers slide past one another like playing cards. There are no cross currents...
airfoil. and widened tail horizontal stabilizer wing area, which improved service ceiling to 8,950 m (29,360 ft) and maximum speed to 437 km/h (236 kn, 272 mph). Main wing fuel tanks were enlarged to 6,490 L (1,715 US gal) which increased the range to 6,100 km (3,790 mi/ 3,294 nmi overloaded, one way). An electrically powered dorsal turret featuring a 20 mm cannon was introduced in place of G4M1's dorsal position with a 7.7 mm machine gun, total guns armed were 2 × 20 mm Type 99 cannon (1 × tail turret, 1 × top turret), 4 × 7.7 mm Type 92 machine gun (1 × nose, 2 × waist, 1 × cockpit side). External differences also included increased nose glazing, flush side gun positions instead of blisters, and rounded tips of wings and tail surfaces. These major improvements also made it possible for the G4M2 to carry more powerful bombs; 1 × 1,055 kg (2,326 lb) Type 91
Type 91 torpedo
The Type 91 was an aerial torpedo of the Imperial Japanese Navy which was designed to be launched from an aircraft. It was used in the naval battles of carrier task forces in World War II.The Type 91 aerial torpedo rev.2 won the admiration of the world...
Kai-7 (improved model 7) aerial torpedo
Aerial torpedo
The aerial torpedo, airborne torpedo or air-dropped torpedo is a naval weapon, the torpedo, designed to be dropped into water from an aircraft after which it propels itself to the target. First used in World War I, air-dropped torpedoes were used extensively in World War II, and remain in limited...
or 1 × 800 kg (1,760 lb) bomb or 2 × 500 kg (1,100 lb) bombs or one Type 3 – 800 kg (1,760 lb) no.31 ray-detective type bomb + 12 × 60 kg (130 lb) bombs. This model, G4M2, was put into service in mid-1943.
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G4M2 Model 22Ko: Very similar to previous model. Carried Type 3 Ku Mark 6 search radar and was armed with two 20 mm Type 99 Mark 1
Type 99 cannon
The Type 99-1 cannon and Type 99-2 cannon were Japanese versions of the Oerlikon FF and Oerlikon FFL. They were adopted by the Imperial Japanese Navy in 1939 and served as their standard aircraft autocannon during World War II.-Adoption:...
cannons replacing the 7.7 mm machine guns in the lateral positions.
G4M2 Model 22 Otsu: Dorsal turret cannon changed to longer-barreled 20 mm Type 99 Mark 2.
G4M2a Model 24: Modified Model 22, MK4T Kasei 25 1,340 kW (1,800 hp) engines, with bulged bomb bay doors as standard for larger bomb capacity. Externally distinguishable from the Model 22 by a carburetor air intake on the top of the engine cowling.
G4M2a Model 24 Ko/Otsu: Armament similar to Model 22 Ko/Otsu respectively.
G4M2a Model 24 Hei: Modified 24 Otsu, with one 13.2 mm (.51 in) Type 2 machine gun
Type 2 machine gun
The Type 2 machine gun was developed for aerial use for the Imperial Japanese Navy during World War II. It was an adaptation of the German MG 131 machine gun.-Installations:* Aichi B7A* Mitsubishi A6M5c* Mitsubishi G4M* Nakajima B6N* Yokosuka P1Y...
mounted in tip of the nose cone, radar antenna relocated from that position to above the nose cone.
G4M2b Model 25: One G4M2a modified to MK4T-B Kasei 25 Otsu 1,360 kW (1,825 hp) engines. Only experimental.
G4M2c Model 26: Two G4M2a modified to MK4T-B Ru Kasei 25b 1,360 kW (1,825 hp) engines with turbocharger
Turbocharger
A turbocharger, or turbo , from the Greek "τύρβη" is a centrifugal compressor powered by a turbine that is driven by an engine's exhaust gases. Its benefit lies with the compressor increasing the mass of air entering the engine , thereby resulting in greater performance...
s.
G4M2d Model 27: One G4M2 modified to MK4V Kasei 27 1,340 kW (1,800 hp) engines.
G4M2e Model 24 Tei: Special version for the transport of the ramming attack bomb plane Kugisho/Yokosuka MXY-7 Ohka
Ohka
The Yokosuka MXY-7 Ohka was a purpose-built, rocket powered human-guided anti-shipping kamikaze attack plane employed by Japan towards the end of World War II...
("Baka") Model 11, conversions of G4M2a Models 24 Otsu and 24 Hei. Had armour protection for the pilots and fuselage fuel tanks.
MXY11 Yokosuka Navy Type 1 Attack Bomber: Ground Decoy Non-flying replica of Mitsubishi G4M2 developed by Yokosuka
G4M3
Self-sealing fuel tank
In aviation, self-sealing fuel tank is a fuel tank technology in wide use since World War II that prevents fuel tanks primarily on aircraft from leaking fuel and igniting after being damaged by enemy fire....
s, improved armor protection and an entirely new tail gunner's compartment similar to that of late model B-26 Marauders. Wings were also redesigned and the horizontal tailplane was given dihedral. Armed with 2 × 7.7 mm Type 92 machine gun
Type 92 machine gun
The was developed for aerial use for the Imperial Japanese Navy before World War II. It was the standard hand-held machine gun in multi-place IJN aircraft during the most part of the Pacific War. It proved to be seriously inadequate...
s in nose cabin and in both side positions, and 1 × 20 mm Type 99 Model 1 cannon in dorsal turret and tail. Entered production in October 1944 in G4M3a Model 34 Ko form with 20 mm cannon in side positions instead of machine guns.
G4M3a Model 34 Otsu and Hei: Similar modifications as in corresponding Model 24 variants.
G4M3 Model 36: Prototype. Two G4M2 Model 34 modified to Mitsubishi MK4-T Kasei 25b Ru 1,360 kW (1,825 hp) engines.
G6M1
G6M1 Japanese Navy Long Range Heavy Fighter Type 1:Initial model of the series, armed with 20 mm Type 99 cannons between each side of fuselage and in tail, 1 × 7.7 mm machine gun in nose cabin and 1 × 30 mm cannon in front ventral position; 30 built.G6M1-K Trainer, Japanese Navy Type 1:Converted G6M1s.
G6M1-L2 Transport Type 1, Japanese Navy:Modified as transports.
Operators
- Imperial Japanese Navy Air ServiceImperial Japanese Navy Air ServiceThe Imperial Japanese Navy Air Service was the air arm of the Imperial Japanese Navy during World War II, the organization was responsible for the operation of naval aircraft and the conduct of aerial warfare in the Pacific War.It was controlled by the Navy Staff of the Imperial Japanese Navy and...
operated the type during 1941–1945 in a total of 37 kokutaiSentaiin Japanese language is a word for a military unit and may be literally translated as "squadron", "task force", "group" or "wing". The terms "regiment" and "flotilla", while sometimes used as translations of Sentai, are also used to refer to larger formations....
(air groupsGroup (air force unit)A group is a military aviation unit, a component of military organization and a military formation. Usage of the terms group and wing differ from one country to another, as well as different branches of a defence force, in some cases...
).
- Royal Air ForceRoyal Air ForceThe Royal Air Force is the aerial warfare service branch of the British Armed Forces. Formed on 1 April 1918, it is the oldest independent air force in the world...
operated at least one captured aircraft for evaluation purposes.
United States
- United States Air ForceUnited States Air ForceThe United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of...
, like the RAF, operated captured aircraft for evaluation.