Mitsubishi Ki-67 Hiryu — History, Specs & Photos

Mitsubishi Ki-67 Hiryu heavy bomber in flight during the Second World War
Aircraft MuseumHeavy BomberKi-67 Hiryu

Mitsubishi Ki-67
“Hiryu” · “Peggy”

Fast, well-armoured and hard-hitting — widely regarded as arguably the best Japanese bomber of the war, yet it reached the front too late and in too few numbers to change anything.

1942First flight · 27 December
~537 km/hTop speed · 334 mph
~698Built · figures vary
1944–1945Front-line service
Photo: Imperial Japanese Army / U.S. wartime record · Public domain (Wikimedia Commons)
RoleTwin-engine heavy bomber · torpedo bomberEraWWII · 1944–1945Engine2 × Mitsubishi Ha-104 radialOriginJapan · MitsubishiStatusRetired · no complete survivorCan you still fly a Ki-67?
The Story

The best bomber Japan built — and the one that came too late

By 1940 the Imperial Japanese Army had watched its bombers burn. The Ki-21 “Sally” and the Navy’s G4M “Betty” could fly far, but they were lightly armed and almost unprotected — no meaningful crew armour, no self-sealing fuel tanks, and a fatal tendency to catch fire when hit. So when the Army issued the specification that became the Ki-67, it asked for something different: a fast, tough, survivable bomber that could defend itself and still reach out across the Pacific.

Mitsubishi delivered. The prototype first flew on 27 December 1942, and what emerged was, by common consent, the finest bomber the Japanese Army ever fielded — and one of the better twin-engine bombers of any nation. Powered by two Mitsubishi Ha-104 radials, the Ki-67 “Hiryu” (“Flying Dragon”) was quick, with a top speed of roughly 537 km/h (334 mph), and — most unusually for a Japanese design — it was protected: self-sealing tanks, armour for the crew, and a heavy defensive battery built around a 20 mm cannon.

It flew like nothing the Army had operated before. Test crews found it could be thrown around almost like a fighter — rolled, looped and turned tightly — a level of agility no earlier Japanese heavy bomber came close to. Allied intelligence gave it the reporting name “Peggy”, and would soon meet it in the torpedo-attack role off Formosa and the Philippines.

And yet the Ki-67’s story is a study in too little, too late. It did not reach front-line units until the summer of 1944, with its combat debut in October 1944. By then Japan had lost its trained aircrews, its fuel and its air superiority. Only about 698 were built (figures vary), against thousands of Allied aircraft — never enough to matter.

What service it did see was intense and often desperate. Ki-67 units flew anti-shipping torpedo strikes against the U.S. Navy off Formosa and the Philippines, level-bombing raids, and home-defence sorties. Many were stripped and packed with explosives for kamikaze “To-Go” special-attack units. And the airframe spawned the Ki-109, a dedicated bomber-destroyer meant to knock down B-29s with a 75 mm cannon.

Everything Japan had learned about protection and performance, arriving in 1944 — a superb aircraft, delivered to a war already lost.The “Hiryu” paradox — the right bomber at the wrong time
01The Mitsubishi Ki-67 Hiryu’s late arrival: why Japan’s best bomber could not change the war

The Ki-67 was specified in late 1940, first flew at the end of 1942 and was accepted as the Army Type 4 Heavy Bomber in December 1943 — but did not reach operational units in numbers until the middle of 1944. That two-year gap between first flight and front-line service was fatal to its impact. By the time crews were flying it in combat from October 1944, the U.S. Navy fielded overwhelming fighter cover and radar-directed anti-aircraft fire, and Japan had neither the fuel nor the experienced aircrew to exploit a good aeroplane. With only about 698 completed across four production sites, the Ki-67 was always a rare sight in a sky filled with Allied machines. It was, in short, an excellent design that history handed too few chances — a recurring theme for late-war Japanese aviation.


Design & Engineering

What made the Ki-67 different

01

Protection, at last

Where earlier Japanese bombers left their crews and fuel exposed, the Ki-67 was built with self-sealing fuel and oil tanks and armour plating from the outset. It was the feature that mattered most in 1944: a Ki-67 that took hits could keep flying and keep its crew alive, where a Betty or a Sally would burn. This single change is the core of its reputation.

02

Two Ha-104s and fighter-like handling

Two Mitsubishi Ha-104 18-cylinder radials of about 1,900 hp each gave a top speed near 537 km/h and a ceiling around 9,470 m. Combined with a strong, clean airframe, they gave the Ki-67 genuine agility — test crews reported it could be rolled and turned in ways no earlier Japanese heavy bomber could match.

03

A heavy defensive sting — and a torpedo

Defence was built around a 20 mm Ho-5 cannon (usually in the dorsal turret) backed by four to five 12.7 mm heavy machine guns in the nose, tail and beam positions. The bomb bay could carry roughly 800 kg of bombs — or a single aerial torpedo, the weapon that defined its combat career against U.S. warships.

02The Ki-67 Hiryu’s manoeuvrability: a heavy bomber that could roll

Contemporary and post-war accounts consistently single out the Ki-67’s handling. Where most heavy bombers are deliberately stable, stately machines, the Hiryu was stressed for higher manoeuvre loads and reportedly demonstrated aerobatic-style manoeuvres during trials — rolls and tight turns more associated with fighters. In service this agility mattered twice over: it helped crews jink away from interceptors, and it made the type suitable for the low, fast torpedo runs the Army began flying against Allied shipping. It is one reason the Ki-67 is often called not just the best Japanese bomber but one of the finest twin-engine bombers of the war — though, as ever with rare late-war types, some of the superlatives should be read as informed judgement rather than hard statistics.


Technical Data

Mitsubishi Ki-67-I Hiryu full specifications

Baseline note: the figures below describe the Ki-67-I — the Ki-67-Ia, Army Type 4 Heavy Bomber Model 1, the main production aeroplane — at normal loaded weight with the standard Ha-104 installation. This is the aircraft that flew the Formosa and Okinawa torpedo strikes and made up the overwhelming majority of the run. Deltas for the factory-fitted torpedo carrier and for the Ki-109 heavy interceptor are given in grey.

Dimensions & weights

Crew
6 to 8 (pilot, co-pilot, navigator-bombardier, radio operator and two to four gunners; Ki-109 flew with a reduced crew including a dedicated cannon loader)
Length
18.70 m (61 ft 4 in) — Ki-109 17.95 m (58 ft 11 in)
Wingspan
22.50 m (73 ft 10 in) — unchanged on every service variant
Height
7.70 m (25 ft 3 in); sources disagree sharply and 5.80 m (19 ft 0 in) is quoted just as often, almost certainly a tail-down versus fin-top measurement
Wing area
65.85 m2 (708.8 sq ft)
Wing loading
209 kg/m2 (42.8 lb/sq ft) at loaded weight
Empty weight
8,649 kg (19,068 lb) — Ki-109 7,424 kg (16,367 lb) with the bomb gear deleted
Loaded weight
13,765 kg (30,347 lb) — Ki-109 10,800 kg (23,810 lb)
Power-to-weight
0.21 kW/kg (0.125 hp/lb) at loaded weight
Internal bomb bay
800 kg (1,764 lb) rated; some authorities quote a 1,070 kg (2,360 lb) overload figure
External store station
One centreline rack for a single Type 91 aerial torpedo, standard from airframe number 161 onwards
Structure
All-metal stressed skin mid-wing monoplane, retractable tailwheel undercarriage, built around large sub-assemblies for fast production

Performance

Maximum speed
537 km/h (334 mph) at 6,090 m (19,980 ft)
Cruising speed
400 km/h (249 mph) at 8,000 m (26,250 ft)
Demonstrated dive speed
644 km/h (400 mph), a figure no other Japanese bomber came near
Time to 6,000 m
14 min 30 s (to 19,685 ft)
Service ceiling
9,470 m (31,070 ft); the Ki-109 as built shared it, and the 12,000 m (39,370 ft) sometimes quoted belongs to the turbocharged Ha-104 Ru that never worked
Normal range
2,800 km (1,740 miles)
Maximum ferry range
3,800 km (2,360 miles)
Ki-109 maximum speed
550 km/h (342 mph) — faster than the bomber, and still not fast enough
Ki-109 range
2,200 km (1,370 miles)
Against US mediums
537 km/h (334 mph) versus 443 km/h (275 mph) for the B-25 and 462 km/h (287 mph) for the B-26
Handling
Aerobatic — service crews looped and rolled it; the specification demanded dive-bombing attacks and a low-level escape, and the airframe delivered both

Propulsion & systems

Engines
Two Mitsubishi Ha-104 (Army Type 4 1,900 hp Air Cooled Radial), 18-cylinder two-row air-cooled radials
Take-off power
1,417 kW (1,900 hp) each
Rated power
1,350 kW (1,810 hp) at 2,200 m (7,220 ft); 1,201 kW (1,610 hp) at 6,100 m (20,010 ft)
Supercharging
Two-speed geared supercharger — the exhaust-turbocharged Ha-104 Ru was flown on three Ki-67-I Kai airframes and was intended for the Ki-109, but was never made reliable
Propellers
Four-blade constant-speed metal units, one per engine
Fuel system
Self-sealing tanks in the wings, fitted from the first production aircraft rather than retrofitted after losses — the single most un-Japanese thing about the design
Crew protection
Armour plate at the crew stations and gun positions, again designed in from the start; the 1941 specification explicitly demanded the ability to absorb battle damage
Dorsal turret
Power-operated turret mounting the single 20 mm Ho-5, the heaviest defensive gun on any Japanese bomber in quantity service
Special equipment
Taki-1 Model II radar on one early-warning conversion; one further airframe was wired as a mother ship for radio-command anti-ship missiles
Ki-109 gun installation
Type 88 75 mm in a fixed nose mount, 15-round magazine, automatic case ejection with hand loading, muzzle velocity 720 m/s (2,360 ft/s); the pilot aimed and fired it himself
Manufacture
Mitsubishi Nagoya as prime contractor, with Kawasaki at Gifu, Nippon Kokusai, and the First Army Air Arsenal at Tachikawa
03Ki-67 Hiryu variants: the Ki-67-I Kai suicide aircraft and the Ki-109 B-29 destroyer

The main production version was the Ki-67-I, built as the Ia and — from around the 451st airframe — the Ib, which swapped the single 12.7 mm tail gun for a twin mounting. A planned Ki-67-Ic with a heavier bomb load never entered production, and the more powerful Ki-67-II (with Ha-214 engines) was not completed before the war ended. Two derivatives stand out. The Ki-67-I Kai was a special-attack (kamikaze) conversion: turrets removed, a long nose rod to detonate the warhead, and a very heavy explosive load; roughly a dozen were operational by October 1944 in the “To-Go” force. The Ki-109 was a dedicated bomber-destroyer fitted with a 75 mm Type 88 cannon to attack B-29 Superfortresses at altitude — an imaginative idea that achieved little, largely because the aircraft’s high-altitude performance was inadequate for the interception role (an assessment on which sources broadly agree, though few combats were recorded).

04The Mitsubishi Ki-67 Hiryu’s operating costs: why the numbers were never kept

Unlike a modern jet, no reliable unit cost or cost-per-flight-hour figure survives for the Ki-67. Japan’s wartime industry was strained, accounting was disrupted, and cost data for individual 1944–45 airframes was neither standardised nor preserved. What the record does show is the price that mattered in 1944: fuel and trained aircrew, both of which Japan had all but run out of by the time the Ki-67 arrived. We have therefore marked the cost fields “not reliably recorded (WWII)” rather than invent a figure — the honest answer for almost every late-war Japanese type.


Armament & payload

The Ki-67 was the Japanese bomber that could actually shoot back

Japanese bombers are routinely criticised for burning at the first hit and for defending themselves with rifle-calibre popguns. The Ki-67 is the standing counter-example: a power-operated dorsal turret with a belt-fed 20 mm Ho-5, four 12.7 mm Ho-103 heavy machine guns covering the nose, both beams and the tail, self-sealing tanks and crew armour built in from airframe one. What it did not have was payload — 800 kg in a single internal bay is a light load for a machine the Army called a heavy bomber — and in practice the type earned its keep with one weapon hung outside, the Type 91 aerial torpedo. Gun fits varied: early aircraft carried magazine-fed 7.7 mm Type 89 guns in the beam blisters until Ho-103s were available, and the late Ki-67-Ib rebuilt the tail position around 20 mm.

Gun

  • One 20 mm Ho-5 cannon in the power-operated dorsal turret, belt-fed, firing the shortened 20×94 mm round
  • Four 12.7 mm Ho-103 (Type 1) machine guns: one in the glazed nose, one in each beam blister, one in the tail
  • Ki-67-Ib: the tail position reworked for 20 mm; some references describe a twin 20 mm tail installation on the last aircraft
  • Early production carried 7.7 mm Type 89 machine guns in the beam positions as an interim fit
  • Ki-109: everything above deleted except one trainable 12.7 mm Ho-103 in the tail, the upper and beam positions faired over

Air-to-air

  • No air-to-air missile existed in 1944; the bomber version fought fighters with its defensive guns alone, and those guns were unusually good at it
  • The one purpose-built anti-aircraft weapon in the family was the Ki-109 nose gun: a Type 88 75 mm field anti-aircraft piece, 15 rounds, 720 m/s muzzle velocity
  • The Type 88 was accurate against ground targets in trials and very hard to aim at a moving bomber; the test pilot Major Sakamoto said flatly that the aiming problem was never solved
  • A projected night-fighter Ki-109 with twin 37 mm Ho-203 in an upward-firing oblique mount, on the German Schräge Musik pattern, stayed on paper
  • An earlier scheme paired a radar-and-beam "hunter" Ki-109a with a gun-armed "killer" Ki-109b; it was abandoned in favour of the 75 mm single-seat solution

Air-to-surface guided

  • Unusually for the period, this card is not empty: one Ki-67 was converted as the mother ship for Japan's radio-command anti-ship missiles
  • Kawasaki Ki-147 I-Go-1A: rocket-powered, radio-guided, roughly 800 kg warhead, launched from beneath the bomber
  • Mitsubishi Ki-148 I-Go-1B: a smaller companion weapon of about 300 kg warhead weight
  • Trials fittings also covered the Ke-Go infra-red homing bomb and several related Go-series projects
  • None of it reached an operational unit; the guided-weapon programmes were overtaken by the decision to use the aeroplane itself as the guidance system

Bombs

  • 800 kg (1,764 lb) rated internal load in one bay, typically eight 100 kg or four 250 kg weapons
  • A maximum of 1,070 kg (2,360 lb) appears in several accounts and in the Wikipedia article text, against 800 kg in the same article's data table
  • Ki-67 To-Gō special-attack conversion: turrets removed and faired over, two 800 kg (1,764 lb) bombs in the belly
  • Ki-167 Sakura-dan: one 2,900 kg (6,393 lb) shaped-charge thermite bomb behind the crew cabin, blast projected forward, nine converted
  • By comparison a B-25 could lift 2,722 kg (6,001 lb) — the Ki-67 was a heavy bomber only in the Japanese Army's sense of the phrase, meaning protection and defence rather than tonnage

Rockets

  • None. No air-to-ground or air-to-air rocket was ever cleared for the Ki-67 or the Ki-109
  • No rocket-assisted take-off gear was fitted either, despite the type's high operating weights
  • The only rocket motor in the story belongs to the Ki-147 missile the aircraft was meant to carry, not to the aircraft
  • Japanese anti-bomber rocketry of 1944–45 went to single-seat interceptors; the Ki-109 was given a field gun instead, which is a fair summary of the whole programme

Pods & other stores

  • One Type 91 aerial torpedo on an external centreline rack — the store that defined the type's combat career
  • Torpedo racks were ordered onto 100 aircraft on 5 January 1943 and became standard from airframe number 161; over 420 machines were completed or modified as torpedo carriers
  • Additional internal fuel for the one-way Giretsu raiding missions against the Marianas B-29 bases
  • Taki-1 Model II early-warning radar on a single conversion — an airborne early warning aircraft in 1945, and almost nobody notices
  • Glider-towing gear, tested with the Manazuru transport glider

Three typical loadouts

Anti-shipping torpedo strike, Formosa, October 1944
One Type 91 torpedo on the centreline rack, bomb bay empty, full ammunition for the 20 mm turret and the four 12.7 mm guns. Flown by the Army's 7th and 98th Sentai and the Navy's 762nd Kōkūtai against the US Third Fleet — the type's combat debut and its most effective use.
Level bombing, China and French Indochina, 1945
800 kg internal, usually eight 100 kg bombs, full crew of seven or eight, all gun positions manned. Cruise at 400 km/h (249 mph) around 8,000 m (26,250 ft), where the bomber's speed and ceiling made interception genuinely difficult.
Special attack, To-Gō and Sakura-dan, 1945
Turrets and defensive guns stripped and faired over, crew reduced. Either two 800 kg bombs in the belly or the single 2,900 kg Sakura-dan shaped charge. The best-protected bomber Japan built, flown deliberately into a ship.

Sourcing caveat: the machine-gun count is genuinely contested. Wikipedia's data table states five 12.7 mm guns while enumerating only four positions; Francillon and Pacific Wrecks both give four (nose, two beams, tail) plus the single 20 mm turret gun, and that is the figure used here. Bomb load is quoted as either 800 kg or 1,070 kg depending on whether the source is describing the rated or the overload case. Production totals are equally unsettled — see the closing note below.


Variants

The Ki-67 arrived too late to be a bomber and was converted into everything else

The Ki-67 first flew on 27 December 1942 and did not reach a combat unit until October 1944. That gap is the whole tragedy of the aeroplane. It was specified in 1941 against a possible war with the Soviet Union over Manchuria, and it was built to survive that war: good defensive armament, self-sealing tanks, armour, and enough manoeuvrability to dive-bomb and then run away at low level. By the time it existed in numbers, the war it was designed for was not the war Japan was losing.

So it was spent on other things. Almost immediately it became a torpedo bomber — racks were ordered onto 100 airframes in January 1943 and the fit became standard from aircraft 161, with more than 420 machines completed as torpedo carriers. It went to the Navy as well as the Army, an unusual step, flying as the "Yasukuni" with the 762nd Kōkūtai. It was then progressively stripped of the very features that made it good: the To-Gō and Sakura-dan conversions had their turrets removed and faired over and were flown into ships. The best-protected Japanese bomber of the war ended it as a guided weapon with a man inside.

The Ki-109 deserves its own paragraph, because it is the most instructive failure in the family. Major Hideo Sakamoto's proposal to bolt an Army Type 88 75 mm anti-aircraft gun into the nose was approved on 20 February 1944; the prototype flew that August and 22 production aircraft followed. The reasoning was sound on paper: a big, fast, docile airframe standing off outside the B-29's defensive fire and killing it with one shell. It failed for three separate reasons, any one of which was fatal. The turbocharged Ha-104 Ru engines that were supposed to give it altitude never became reliable, so the aircraft as built could not climb to the B-29's cruise height with anything in hand. It had no radar. And the gun — hand-loaded from a 15-round magazine, aimed by the pilot — could not be pointed accurately at a moving target. The 107th Heavy Fighter Regiment was disbanded on 30 July 1945 without a confirmed B-29.

Ki-67-I prototypes (1942–43 / 19)
Development airframes with a variety of gun fits; first flight 27 December 1942.
Ki-67-Ia, Army Type 4 Heavy Bomber Model 1 (1944–45 / the bulk of the run)
Main production model. Most were completed or converted as torpedo carriers after work number 160.
Ki-67-Ib (1945 / late production)
Reinforced tail position rebuilt around 20 mm armament in place of the 12.7 mm gun.
Ki-67-I Kai (1945 / 3)
Testbeds for the exhaust-turbocharged Mitsubishi Ha-104 Ru, the engine the Ki-109 needed and never got.
"Yasukuni" (1944–45 / Army transfers)
Navy torpedo-bomber version, Ki-67-Is handed from the Army to the Imperial Japanese Navy Air Service.
Ki-67 To-Gō (1944–45 / conversions)
Army Special Attack Aircraft Type 4: unarmed, turrets deleted and faired, two 800 kg bombs in the belly.
Ki-167 Sakura-dan (1945 / 9)
Special attack conversion carrying one 2,900 kg shaped-charge thermite bomb with a forward-directed blast.
Ki-67-II (1945 / 2)
Prototypes with two Mitsubishi Ha-214 engines of 1,581 kW (2,150 metric hp) each. No production.
Ki-109 (1944–45 / 2 prototypes and 22 production)
Heavy fighter interceptor with a fixed Type 88 75 mm cannon in the nose, bomb gear and upper and beam guns deleted.
Q2M1 Tai'yō, Ki-69, Ki-97, Ki-112 (projects only)
Navy anti-submarine derivative with Kasei engines and radar, escort fighter, transport, and an all-wood escort fighter. None built.

Production and survivors. Totals disagree: 767 is the figure usually printed, while other accounts give 698 excluding the Kai and Sakura-dan conversions, and the factory sub-totals quoted by different authorities (587 or 606 by Mitsubishi, 91 by Kawasaki at Gifu, 29 by Nippon Kokusai, 1 by the Tachikawa arsenal) do not reconcile with either headline number. As for what is left: no complete Ki-67 survives anywhere in the world. No original airframe is preserved in any museum, none is airworthy, and no flying or static reproduction has been built. What exists is fragmentary — recovered components and jungle and lagoon wreck sites in the former Pacific theatre. For an aircraft that was arguably the finest bomber Japan produced, the physical record is close to nothing, which is a large part of why it is so little remembered.


Timeline

From a 1940 specification to the last Pacific torpedo runs

1940

The Army asks for a survivable bomber

Late in 1940 the Imperial Japanese Army issues the specification that becomes the Ki-67 — explicitly demanding speed, defensive firepower and protection its earlier bombers had lacked.

1942

First flight

The prototype flies on 27 December 1942. Trials reveal an unusually agile heavy bomber with fighter-like handling.

1943

Accepted as the Type 4 Heavy Bomber

The design is frozen and accepted in December 1943 as the Army Type 4 Heavy Bomber, Model 1A — the “Hiryu”.

1944

Enters service

Deliveries to operational units begin in the summer of 1944, far later than Japan needed them and against a tightening Allied advance.

Oct 1944

Combat debut off Formosa

Ki-67 torpedo units strike U.S. Navy task forces during the Formosa Air Battle — the type’s first major action, and a taste of its anti-shipping role.

Late 1944

Special attack and the B-29 hunter

Ki-67-I Kai aircraft are converted for kamikaze “To-Go” missions over the Philippines, while the Ki-109 derivative is fielded to hunt B-29s with a 75 mm cannon.

1945

Okinawa and home defence

Ki-67s fly torpedo, bombing and special-attack sorties around Okinawa and in defence of the home islands during the final months of the war.

Aug 1945

War’s end — and no survivors

Production ends at roughly 698 aircraft. None would survive intact; today only relics and captured components remain.


Stories & Eyewitnesses

Twelve stories of the Ki-67 “Hiryu”

Origins · 1940

A bomber designed not to burn

The Army had seen its bombers flamed out of the sky. This time it demanded protection first.

Read the full story
By 1940, combat over China and the early Pacific had taught the Imperial Japanese Army a brutal lesson: range and speed were worthless if a single burst of fire turned the aircraft into a torch. The specification that produced the Ki-67 broke with Japanese practice by insisting on self-sealing tanks, crew armour and a heavy defensive battery. It was an admission that the “lightly built, long-legged” philosophy of the Ki-21 and G4M had failed — and the start of Japan’s best bomber.
Design · 1942

First flight of something different

On 27 December 1942 the prototype lifted off — and the test crews were startled by how it flew.

Read the full story
The Hiryu’s maiden flight revealed an aeroplane that behaved unlike any heavy bomber Mitsubishi had built. Stressed for higher loads and aerodynamically clean, it could be manoeuvred with a briskness normally reserved for fighters. That agility was not a gimmick: it shaped how the Ki-67 would be used, from evasive routing against interceptors to the low, fast torpedo runs its crews would later fly against American warships.
Protection · 1943

Self-sealing tanks and armour

The feature that mattered most was the one you couldn’t see: the Ki-67 was built to take a hit.

Read the full story
Self-sealing fuel and oil tanks and armour plating were designed into the Ki-67 from the beginning — a genuine rarity among Japanese aircraft, which typically traded protection for range. In the survivability-driven air war of 1944–45 this was decisive: a damaged Hiryu could bring its crew home where earlier types could not. It is the single reason the Ki-67 is so consistently rated the best bomber the Japanese Army operated.
Handling

The heavy bomber that could roll

Accounts describe aerobatic-style manoeuvres during trials — extraordinary for a twin-engine bomber.

Read the full story
Manoeuvrability is the quality most often cited when the Ki-67 is compared with the best twin-engine bombers of any nation. Reports of the type performing rolls and tight turns during testing reflect an airframe stressed well beyond the usual bomber limits. Treat the more dramatic claims with a little caution — few figures survive — but the consensus of pilots and historians is clear: the Hiryu was unusually nimble for its class.
Name

“Flying Dragon” and “Peggy”

To Japan it was “Hiryu”. To Allied intelligence it became, simply, “Peggy”.

Read the full story
“Hiryu” — 飛龍, “Flying Dragon” — was the poetic Japanese name for the Army Type 4 Heavy Bomber. The Allied reporting-name system, which assigned female names to bombers and male names to fighters, filed it as “Peggy”. The two names capture the aircraft’s split reputation: a proud symbol of Japan’s most advanced bomber, and a respected, dangerous adversary in Allied recognition manuals.
Combat · Oct 1944

Torpedoes off Formosa

The Ki-67’s first big action was an anti-shipping strike against the U.S. fleet.

Read the full story
During the Formosa Air Battle of October 1944, Ki-67 units flew torpedo attacks against the ships of the U.S. Navy’s fast carrier task forces. It was the type’s combat debut and a preview of its most distinctive role. Japanese claims from the battle were wildly optimistic, but the strikes showed that the Army now had a fast, survivable torpedo bomber — even if there were never enough of them, or enough trained crews, to press the advantage.
Anti-shipping

An Army bomber learns the torpedo

Attacking warships with torpedoes had been the Navy’s trade. The Ki-67 brought it to the Army.

Read the full story
The Ki-67 could carry a single aerial torpedo, and specialised units used it against Allied shipping off Formosa, the Philippines and later Okinawa. Torpedo work demanded exactly what the Hiryu offered — speed, agility and the toughness to survive a low, straight run into defensive fire. It remains one of the few examples of a Japanese Army bomber taking on a classic maritime-strike mission.
Philippines · 1944

Fleet strikes and heavy losses

Over the Philippines the Ki-67 fought hard — and was ground down.

Read the full story
As the U.S. invaded the Philippines in late 1944, Ki-67 units joined the furious air battles over Leyte and Luzon, flying bombing and torpedo missions against the invasion fleet. Facing overwhelming fighter cover and radar-directed flak, losses were severe, and numbers of the rare bomber were destroyed on the ground or captured — the wreck famously photographed at Clark Field in August 1945 among them.
To-Go · special attack

The Hiryu as a flying bomb

Some of Japan’s best bombers were deliberately expended as guided weapons.

Read the full story
As the war turned desperate, Ki-67-I Kai aircraft were stripped of turrets, fitted with a nose detonator rod and packed with explosives for kamikaze missions in the “To-Go” special-attack force — roughly a dozen operational by October 1944. There is a bitter irony in it: the one Japanese bomber built above all to bring its crew home was, in its final role, flown on a one-way trip.
Ki-109 · B-29 hunter

A 75 mm cannon against the Superfortress

The Hiryu airframe was reworked into a heavy interceptor to knock down B-29s.

Read the full story
The Ki-109 mounted a 75 mm Type 88 cannon in the nose, the idea being to stand off from B-29 formations and destroy them with a few heavy rounds where lighter guns failed. It was inventive, but the concept foundered on physics: the converted bomber simply could not reach and hold the altitudes at which the B-29s cruised, and it achieved little in practice. Sources broadly agree the Ki-109 was a technical curiosity rather than an effective interceptor.
Numbers

~698 — and too late

Japan’s finest bomber was also one of its rarest.

Read the full story
Roughly 698 Ki-67s were completed across Mitsubishi, Kawasaki, Nippon Kokusai and a single Army-arsenal example — a tiny total for a two-year production run, and a fraction of what a decisive campaign would have required. Entering service in mid-1944 against an enemy already winning, the Hiryu could fight well but never in the numbers that might have mattered. Its lateness, not its design, is the real reason it left so little mark.
Legacy

No complete Hiryu survives

The best bomber Japan built left almost nothing behind.

Read the full story
Not one complete Ki-67 survives anywhere in the world. What remains are relics and components — fragments recovered from the Pacific, museum-held parts, and detailed scale models such as those at Japan’s Kakamigahara Aerospace Museum. For an aircraft so highly rated by the pilots and historians who study it, the absence of a single airworthy or even complete static example is a striking reminder of how thoroughly the type was consumed by the war’s final year.

Gallery

The Ki-67 “Hiryu” in pictures

Mitsubishi Ki-67 Hiryu bomber captured by the United States at the end of World War II
A Ki-67 “Hiryu” captured largely intact at the end of the war — very few fell into Allied hands. Photo: U.S. wartime record · Public domain (Wikimedia Commons)
United States airman inspecting a captured Mitsubishi Ki-67 bomber
A U.S. Army Air Forces airman makes notes on a captured Ki-67 — Allied intelligence rated “Peggy” a dangerous opponent. Photo: U.S. Army Air Forces · Public domain (Wikimedia Commons)
Wreck of a Mitsubishi Ki-67 at Clark Field, Philippines, August 1945
The wreck of a Ki-67 at Clark Field, Philippines, 1 August 1945 — a marker of the fierce, costly Philippines air battles. Photo: U.S. Army Air Forces · Public domain (Wikimedia Commons)
Detailed model of the Mitsubishi Ki-67 Peggy in Imperial Japanese Army markings
A detailed model of a Ki-67 in Imperial Japanese Army markings — no complete airframe survives anywhere. Photo: 先従隗始 · CC0 (Wikimedia Commons)
1/20 scale model of the Mitsubishi Ki-67 Hiryu at the Kakamigahara Aerospace Museum
A 1/20 model of the Ki-67 “Hiryu” at Japan’s Gifu-Kakamigahara Air and Space Museum. Photo: Motokoka · CC BY-SA 4.0 (Wikimedia Commons)
Second view of the 1/20 scale Mitsubishi Ki-67 Hiryu model at Kakamigahara
Another view of the 1/20 Ki-67 “Hiryu” model at Kakamigahara — the closest thing to a surviving Hiryu. Photo: Motokoka · CC BY-SA 4.0 (Wikimedia Commons)

Watch

The Ki-67 “Hiryu” in motion

IHYLS: Japan’s Best “Heavy” Bomber Wasn’t Very Heavy — Mitsubishi Ki-67 Hiryu. A focused documentary on the type’s design, protection, torpedo role and the Ki-109 derivative (roughly 65,000 views and a 99% positive rating from an established aviation-history channel).


Operations

Where the Ki-67 flew and fought


Combat Record

The Ki-67’s war, in three numbers

The Ki-67 was a survivable, hard-hitting bomber that arrived far too late to shape the outcome. Its record is best measured not in decisive victories but in a short, intense operational life squeezed into the war’s final year.

~698Built across four sites — a tiny total for a two-year run (figures vary)
Oct 1944Combat debut — torpedo strikes off Formosa, barely ten months before the war ended
0Complete airframes surviving today — only relics and components remain

Compare the combat record of every military aircraft.


Questions & Answers

Everything people ask about the Mitsubishi Ki-67 Hiryu

Can I fly in a Mitsubishi Ki-67?
No — it is impossible. There are no airworthy Ki-67s anywhere, and not a single complete example survives even as a static museum aircraft; only relics and captured components remain. MiGFlug does not offer, and cannot offer, flights in a Ki-67. You can, however, fly in several genuine ex-military jets today — see migflug.com/flights-prices/.
Why is the Ki-67 called the best Japanese bomber of the war?
Because, unusually for a Japanese design, it combined good speed and range with fighter-like manoeuvrability and — crucially — protection: self-sealing fuel tanks, crew armour and a heavy defensive battery including a 20 mm cannon, features earlier types like the Ki-21 and G4M lacked. That balance leads many historians to rate it arguably the best Japanese bomber of the war and one of the finest twin-engine bombers of any nation. It is an informed judgement rather than a hard statistic, so it is fair to say “widely regarded as” rather than to state it as settled fact.
What do “Hiryu” and “Peggy” mean?
“Hiryu” (飛龍) is Japanese for “Flying Dragon”, the poetic name given to the Army Type 4 Heavy Bomber. “Peggy” was the Allied reporting name assigned under the system that gave bombers female names and fighters male names, so Allied crews and recognition manuals knew the aircraft as “Peggy”.
Was the Ki-67 really a torpedo bomber?
Yes. As well as level bombing, the Ki-67 could carry a single aerial torpedo, and specialised Army units used it for anti-shipping strikes against U.S. Navy warships — notably off Formosa (Taiwan) during the Formosa Air Battle of October 1944 and later off the Philippines and Okinawa. Its speed, agility and protection suited the low, fast torpedo run.
What was the Ki-109?
The Ki-109 was a dedicated bomber-destroyer derivative of the Ki-67, fitted with a 75 mm cannon in the nose to attack B-29 Superfortresses from stand-off range. The idea was inventive but largely unsuccessful: the converted aircraft could not reach and sustain the high altitudes at which the B-29s operated, so it achieved little in practice. Few interceptions were recorded, and sources broadly treat it as a technical curiosity.
Were Ki-67s used as kamikaze aircraft?
Yes. Many Ki-67s were expended in special-attack (kamikaze) units — the “To-Go” force — with the Ki-67-I Kai variant stripped of turrets, fitted with a nose detonator rod and packed with explosives. Roughly a dozen were operational by October 1944. It is a bitter irony that the one Japanese bomber built above all to protect its crew was, in this role, flown on one-way missions.
How many Ki-67s were built, and why couldn’t it change the war?
About 698 were completed (figures vary), across Mitsubishi, Kawasaki, Nippon Kokusai and one Army-arsenal example. It entered service only in the summer of 1944 and made its combat debut in October 1944 — by which time Japan had lost air superiority, fuel and experienced aircrew. A fine aircraft in tiny numbers, arriving that late, simply could not alter the outcome.
Do any Ki-67s survive today?
No complete Ki-67 survives anywhere in the world — there is no airworthy example and no intact static airframe. What remains are relics and components: fragments recovered from the Pacific and parts and detailed models held by museums such as Japan’s Gifu-Kakamigahara Air and Space Museum.

Sources & Further Reading

Every fact, checked