Nakajima Ki-84
Encyclopedia
The Nakajima
Nakajima Aircraft Company
The Nakajima Aircraft Company was a prominent Japanese aircraft manufacturer throughout World War II.-History:...
Ki-84 ("Gale") was a single-seat fighter
Fighter aircraft
A fighter aircraft is a military aircraft designed primarily for air-to-air combat with other aircraft, as opposed to a bomber, which is designed primarily to attack ground targets...
used by the Imperial Japanese Army Air Force 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 Allied
Allies of World War II
The Allies of World War II were the countries that opposed the Axis powers during the Second World War . Former Axis states contributing to the Allied victory are not considered Allied states...
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...
was "Frank"; the Japanese Army designation was . Featuring excellent performance and high maneuverability, the Ki-84 was considered to be the best Japanese fighter to see large scale operations during World War II. It was able to match any Allied fighter, and to intercept the high-flying B-29 Superfortress
B-29 Superfortress
The B-29 Superfortress is a four-engine propeller-driven heavy bomber designed by Boeing that was flown primarily by the United States Air Forces in late-World War II and through the Korean War. The B-29 was one of the largest aircraft to see service during World War II...
es. Its powerful armament (that could include two 30 mm and two 20 mm cannon) increased its lethality. Though hampered by poor production quality in later models, a high-maintenance engine, a landing gear prone to buckle,and lack of experienced pilots above all else, Hayates proved to be fearsome opponents. Exactly 3,514 aircraft were built.
Design and development
Imperial Japanese Army Air Service
The , was the land-based aviation force of the Imperial Japanese Army. As with the IJA itself, the IJAAF was developed along the lines of Imperial German Army Aviation so its primary mission was to provide tactical close air support for ground troops while maintaining a limited air interdiction...
requirement for a replacement to Nakajima's Ki-43
Nakajima Ki-43
The Nakajima Ki-43 Hayabusa was a single-engine land-based tactical fighter used by the Imperial Japanese Army Air Force in World War II...
fighter, just entering service. The specification recognized the need to combine the maneuverability of the Ki-43 with performance to match the best western fighters and heavy firepower. The Ki-84 first flew in March 1943
1943 in aviation
This is a list of aviation-related events from 1943:-Events:* Watanabe Iron Works transfers its aircraft manufacturing business to a new subsidiary, the Kyushu Airplane Company Ltd.-January:...
. Although the design itself was solid, the shortage of fuel, construction materials, poor production quality, and lack of skilled pilots prevented the fighter from reaching its potential.
The Ki-84 addressed the most common complaints about the popular and highly maneuverable Ki-43: insufficient firepower, poor defensive armor
Vehicle armour
Military 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....
, and lack of climbing power. The Ki-84 was a cantilever low-wing monoplane of all-metal construction, except for the fabric-covered control surfaces. It had retractable tailwheel landing gear.
Armament comprised two fuselage-mounted 12.7 mm (.50 in) machine gun
Machine gun
A machine gun is a fully automatic mounted or portable firearm, usually designed to fire rounds in quick succession from an ammunition belt or large-capacity magazine, typically at a rate of several hundred rounds per minute....
s and two wing-mounted 20 mm cannon, a considerable improvement over the two 12.7 mm (.50 in) machine gun
Machine gun
A machine gun is a fully automatic mounted or portable firearm, usually designed to fire rounds in quick succession from an ammunition belt or large-capacity magazine, typically at a rate of several hundred rounds per minute....
s used in the Hayabusa. Defensive armor
Vehicle armour
Military 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....
offered Hayate pilots better protection than the unsealed
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....
wing tanks and light-alloy airframe of the Ki-43. In addition, the Ki-84 used a 65 mm (2.56 in) armor-glass canopy, 13 mm (.51 in) of head and back armor, and multiple bulkheads in the fuselage
Fuselage
The fuselage is an aircraft's main body section that holds crew and passengers or cargo. In single-engine aircraft it will usually contain an engine, although in some amphibious aircraft the single engine is mounted on a pylon attached to the fuselage which in turn is used as a floating hull...
, which protected both the methanol-water tank (used to increase the effectiveness of the supercharger
Supercharger
A 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,...
) and the centrally located fuel tank
Fuel tank
A fuel tank is safe container for flammable fluids. Though any storage tank for fuel may be so called, the term is typically applied to part of an engine system in which the fuel is stored and propelled or released into an engine...
.
It was the Nakajima Ha-45 radial powerplant that gave the Hayate its high speed and prowess in combat. Derived from the Homare
Nakajima Homare
|-See also:-Bibliography:* Jane's Fighting Aircraft of World War II. London. Studio Editions Ltd, 1998. ISBN 0-517-67964-7* Gunston, Bill. World Encyclopaedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9...
engine common to many Japanese aircraft, the Hayate used a direct-injection
Gasoline direct injection
In internal combustion engines, gasoline direct injection , also known as petrol direct injection or direct petrol injection, is a variant of fuel injection employed in modern two-stroke and four-stroke gasoline engines...
version of the engine, using water injection
Water injection (engines)
In internal combustion engines, water injection, also known as anti-detonant injection, is spraying water into the cylinder or incoming fuel-air mixture to cool the combustion chambers of the engine, allowing for greater compression ratios and largely eliminating the problem of engine knocking...
to aid the supercharger in giving the Ki-84 a rated 1,491 kW (2,000 hp) at takeoff. This combination—in theory, at least—gave it a climb rate and top speed roughly competitive with the top Allied fighters. Initial Hayate testing at Tachikawa in early summer 1943 saw test pilot 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...
Funabashi reach a maximum level airspeed of 624 km/h (387 mph) in the second prototype. But after the war a late-production, captured example was tested in the US with high octane fuel, and achieved a speed of 687 km/h (426 mph).
The complicated direct-injection engine required a great deal of care in construction and maintenance and, as the Allies advanced toward the Japanese homeland, it became increasingly difficult to support the type's designed performance. Compounding reliability issues was the Allied submarine blockade which prevented delivery of crucial components, such as the landing gear
Undercarriage
The undercarriage or landing gear in aviation, is the structure that supports an aircraft on the ground and allows it to taxi, takeoff and land...
. Many further landing gear units were compromised by the poor-quality heat treatment of late-war Japanese steel. Many Hayates consequently suffered strut collapses on landing.
Operational service
The first major operational involvement was in the battle of LeyteBattle of Leyte
The Battle of Leyte in the Pacific campaign of World War II was the invasion and conquest of the island of Leyte in the Philippines by American and Filipino guerrilla forces under the command of General Douglas MacArthur, who fought against the Imperial Japanese Army in the Philippines led by...
at the end of 1944, and from that moment until the end of the Pacific war the Ki-84 was met wherever the action was intense. The 22nd Sentai re-equipped with production Hayates. Though it lacked sufficient high-altitude performance, it performed well at medium and low levels. Seeing action against the USAAF 14th Air Force, it quickly gained a reputation as a fighter to be reckoned with. Fighter-bomber models also entered service. On April 15, 1945, 11 Hayates attacked US airfields on Okinawa, destroying many aircraft on the ground.
The Ki-84, Ki-100
Kawasaki Ki-100
The Kawasaki Ki-100 was a fighter aircraft used by the Imperial Japanese Army in World War II. The Japanese Army designation was "Type 5 Fighter"...
, and N1K2-J were the three Japanese fighters best suited to combat the newer Allied fighters.
Camouflage and markings
The Ki-84 is known to have appeared in three Japanese Ministry of Munitions sanctioned camouflage schemes;Type N: The entire airframe was left in its original natural metal. Because of the different grades of alloy used for various panels the overall finish soon weathered or oxidized to a pale metallic grey, with variations in shade and texture, depending on the grade of duralumin used for each area of skin. A black "anti-glare" panel was painted on the top forward fuselage and engine cowling (see photo of 73 Hiko-Sentai aircraft).
Type B: Irregular blotches or stripes of dark green on the basic natural metal scheme. This was applied once the aircraft reached its operational base. On occasion the edges of national (hinomaru) and Sentai markings were accidentally covered.
Type S: Three variations were seen on Ki-84s; S1 – Dark green upper surfaces, with light gray/green lower surfaces. S2 – The light gray/green on the lower surfaces was replaced by a pale blue/gray. These colors were often applied on an unprimed airframe; because of this and the poor adhesion of Japanese paints in the later years of the war this scheme often weathered quickly, with large patches of natural metal being visible (see photo of 85 Hiko-Sentai Ki-84 on a Korean base). S10 – The upper surfaces were left in a red/brown primer with the under surfaces in natural metal. The black anti-glare panel was optional.
Other schemes were applied, particularly by the Shinbu-Tai "Special Attack" units. For example, a Ki-84 of 57 Shinbu-Tai, flown by Corporal Takano, had very dark brown-green upper surfaces (some sources state black), with a large red "arrow" outlined in white painted along the entire length of the fuselage and engine cowling. White Kana characters "hitt-chin" (be sure to sink) were painted above the arrow on the rear fuselage. The under surfaces were light gray.
Factory applied markings included six hinomaru
Flag of Japan
The national flag of Japan is a white rectangular flag with a large red disk in the center. This flag is officially called in Japanese, but is more commonly known as ....
(national insignia), outlined with a 75 mm (2.95 in) white border on camouflaged aircraft, on either side of the rear fuselage and on the upper and lower outer wings. Yellow/orange identification strips were applied to the leading edges of wings, extending from the roots to ⅓ rd of the wingspan.
It was a general rule that Japanese planes in overseas territories had a narrow white line called the "border break through line" or "field identification mark" surrounding their hinomaru; planes belonging to interception forces in Japan proper placed the insignia inside a white square (colloquially known as the "Homeland Defense bandage"), so that anti-aircraft defense units could more easily distinguish them from enemy planes.
The inside of the fuselage and the wheel cover wells were painted in a dark opaque bluish gray, and the propeller spinner was painted with a variety of colors based on the unit it belonged to.
Versions
Ki-84-a- Prototype.
Ki-84-b
- Evaluation model.
Ki-84-c
- Pre-production model.
Ki-84-Ia Hayate
- Fighter Type 4 of Army. Armed with 2 × 12.7 mm Ho-103 machine gunHo-103 machine gunThe 12.7mm Type 1 was a Japanese aircraft machine gun widely used during World War II and also known as the Ho-103. The Ho-103 was actually a fixed gun and the Ho-104 a flexible gun...
s and 2 × Ho-5 cannonHo-5 cannonThe Ho-5 was a Japanese aircraft autocannon used during World War II. Developed from the Ho-103 machine gun, it was a version of the American Model 1921 Browning aircraft machine gun. It replaced the Ho-1 and Ho-3 in general service. The Ho-5 was belt-fed using typical Browning-style steel...
in wings (most widely produced version).
Ki-84-Ib
- Version armed with 4 × 20 mm Ho-5 cannonHo-5 cannonThe Ho-5 was a Japanese aircraft autocannon used during World War II. Developed from the Ho-103 machine gun, it was a version of the American Model 1921 Browning aircraft machine gun. It replaced the Ho-1 and Ho-3 in general service. The Ho-5 was belt-fed using typical Browning-style steel...
. (very limited production run. May never have equipped a full Sentai)
Ki-84-Ic
- Version against Bombers, with 2 × 20 mm Ho-5 cannonHo-5 cannonThe Ho-5 was a Japanese aircraft autocannon used during World War II. Developed from the Ho-103 machine gun, it was a version of the American Model 1921 Browning aircraft machine gun. It replaced the Ho-1 and Ho-3 in general service. The Ho-5 was belt-fed using typical Browning-style steel...
and 2 × 30 mm (1.18 in) Ho-155 cannonHo-155 cannonHo-155 was a Japanese aircraft autocannon used during World War II. It was a scaled-up and modified version of the 20 mm Ho-5 cannon, itself a scaled up Model 1921 aircraft Browning.-Specifications:*Caliber: 30 mm...
in wings. (probably never saw squadron strength service)
Ki-84-Ia (Manshu Type)
- Manufactured in Manchukuo for Mansyu by Nakajima License.
Ki-84-II
- Similar to models mentioned above (Ki-84-Ia, -Ib, -Ic).
Ki-84 N/P/R
- High altitude versions.
Ki-106
- Prototypes in total wood construction.
Ki-113
- Prototype similar at Ki-84-Ib in steel.
Ki-116
- Evaluation model, equipped with Mitsubishi 62 (Ha-33), 1,120 kW (1,500 hp).
Ki-117
- Redesigning of Ki-84 N.
Operators
Wartime- Imperial Japanese Army Air ServiceImperial Japanese Army Air ServiceThe , was the land-based aviation force of the Imperial Japanese Army. As with the IJA itself, the IJAAF was developed along the lines of Imperial German Army Aviation so its primary mission was to provide tactical close air support for ground troops while maintaining a limited air interdiction...
Post-war
- People's Liberation Army Air ForcePeople's Liberation Army Air ForceThe People's Liberation Army Air Force is the aviation branch of the People's Liberation Army, the military of the People's Republic of China...
operated captured aircraft from 1945 until the 1950s.
- Chinese Nationalist Air ForceRepublic of China Air ForceThe Republic of China Air Force is the aviation branch of the Republic of China Armed Forces. The ROCAF's primary mission is the defense of the airspace over and around Taiwan...
held some Ki-84 in reserve in case American aid was cut.
Indonesia
- In 1945, Indonesian People's Security Force (IPSF) (Indonesian pro-independence guerrillas) captured a small number of aircraft at numerous Japanese air bases, including Bugis Air Base in Malang (repatriated 18 September 1945). Most aircraft were destroyed in military conflicts between the Netherlands and the newly proclaimed Republic of Indonesia during the Indonesian National RevolutionIndonesian National RevolutionThe Indonesian National Revolution or Indonesian War of Independence was an armed conflict and diplomatic struggle between Indonesia and the Dutch Empire, and an internal social revolution...
of 1945–1949.
Survivors
After the war a number of aircraft were tested by the allied forces, two at the Allied Technical Air Intelligence Unit - South-West Pacific AreaAllied Technical Air Intelligence Unit
The Allied Technical Air Intelligence Unit was a joint group of the United States Navy, United States Army Air Forces, Royal Australian Air Force, and Royal Navy formed in November 1942 to recover Japanese aircraft to obtain intelligence on their technical and tactical capabilities...
(ATAIU-SWPA) as S10 and S17 and a further two in the United States as FE-301 and FE-302 (Later T2-301 and T2-302).
One aircraft was operated and flown by the Planes of Fame
Planes of Fame
Planes of Fame Air Museum is an aviation museum located in Chino, California, and Valle, Arizona. The museum has many flying and static aircraft, along with multiple rare examples under restoration.-History:...
Museum in Chino, California, before being returned to Japan for display at the Arashiyama Museum in Kyoto. This aircraft is now exhibited at the Tokko Heiwa Kinen-kan Museum
Chiran Special Attack Peace Museum
The airbase at Chiran, south Kyūshū, Japan, served as the departure point for hundreds of Special Attack or kamikaze sorties launched in the final months of World War II. A peace museum dedicated to the pilots, the , now marks the site.-Airbase:...
at Chiran, Japan. It is the only surviving Ki-84.
Specifications (Ki-84-Ia)
See also
External links
- Tokko Heiwa Kinen-kan Museum at Chiran, Minamikyushu City
- Miyakonojo Hayate Special Attack Shinbu Corps Monument
- Review of Japanese Ki-84 Hayate publications
- "Song of Hayate fighter squadron", Nippon News, No. 254. in the official website of NHKNHKNHK is Japan's national public broadcasting organization. NHK, which has always identified itself to its audiences by the English pronunciation of its initials, is a publicly owned corporation funded by viewers' payments of a television license fee....
.