View source for Mitsubishi Ki-67

{{Short description|Japanese twin-engine medium bomber}}<!-- This article is a part of [[Wikipedia:WikiProject Aircraft]]. Please see [[Wikipedia:WikiProject Aircraft/page content]] for recommended layout. -->
{{Infobox aircraft
| name = Ki-67 ''Hiryū''
| image = MitsubishiKi67.jpg
| image_border = 
| caption = Mitsubishi Ki-67 of the 170th Bombardment Group on [[Kumamoto Airport|Kengun airfield]], Japan, 1945
| type = [[Medium bomber]]{{Efn|While the Ki-67 was officially designated a "heavy bomber", for the Japanese military the term implied greater crew protection and defensive armament, rather than payload. In all of its key parameters, the type was very similar to the contemporaneous medium bombers of other countries.}}
| national_origin = Japan
| manufacturer = [[Mitsubishi Aircraft Company]]
| designer = 
| first_flight = 27 December 1942
| introduction = October 1944
| retired = August 1945
| status = Retired
| primary_user = [[Imperial Japanese Army Air Service]]
| more_users = [[Imperial Japanese Navy Air Service]]
| produced = 
| number_built = 767
| unit cost = 
| developed_from = 
| variants = [[Mitsubishi Q2M]]
| developed_into = 
}}
The '''Mitsubishi Ki-67''' {{nihongo|''Hiryū''|飛龍|flying dragon}}, Allied [[World War II Allied names for Japanese aircraft|reporting name]] "''Peggy''", was a twin-engine [[bomber]] produced by [[Mitsubishi Aircraft Company]] and used by the [[Imperial Japanese Army Air Service]] and [[Imperial Japanese Navy Air Service]] in [[World War II]]. While its original official designation was {{nihongo|"'''Army Type 4 Heavy Bomber'''"|四式重爆撃機|Yon-shiki jū bakugeki-ki}}, in all of its key parameters, the Ki-67 was similar to the contemporaneous [[medium bomber]]s of other countries.{{efn|At the time, under Japanese military parlance, the designation "heavy bomber" referred to superior crew protection and defensive armament,{{cn|date=May 2023}} rather than the bombloads carried (which, in the Ki-67, were significantly lighter than those carried by true heavy bombers of the same era).}} Japanese Navy variants included the '''P2M''' and [[Mitsubishi Q2M|Q2M]].{{citation needed|date=March 2015}}

==Design==
The Ki-67 was the result of a 1941 Japanese army specification for a successor to the [[Nakajima Ki-49]] "storm dragon". This new aircraft was specified to be a high-speed twin-engined [[heavy bomber]] suitable for possible conflicts with the [[Soviet Union]] over the [[Manchuria]]-[[Siberia]] border, and unlike many Japanese warplanes, was required to have good defensive armament and the ability to survive heavy battle damage. It was also required to be highly maneuverable allowing it to carry out dive-bombing attacks and escape at low level.<ref name="Frnc70p186">{{Harvnb|Francillon|1970|p=186}}</ref><ref name="AIJul83p28">{{Harvnb|''Air International'' July 1983|p=28}}</ref>

The Ki-67 was designed by a team led by Kyūnojō Ozawa, chief engineer at Mitsubishi, and was a mid-winged [[monoplane]] of all-metal construction, with a retractable [[Conventional landing gear|tailwheel undercarriage]]. It was fitted with [[self-sealing fuel tank]]s and [[Vehicle armour|armor]],<ref name="AIJul83p28"/><ref name="Frnc70p187">{{Harvnb|Francillon|1970|p=187}}</ref> features common in US fighters and bombers but frequently lacking in Japanese aircraft. With these features and its two {{convert|1,417|kW|abbr=on}} 18-cylinder air-cooled [[radial engine]]s, the Ki-67 was perhaps one of the most sturdy and damage-resistant Japanese aircraft of World War II.{{citation needed|date=December 2020}}

The Ki-67's bomb load of 1,070&nbsp;kg (2,360&nbsp;lb) carried in its internal bomb bay would classify it as a medium bomber for the US. The [[North American B-25 Mitchell]] could carry up to 2,722&nbsp;kg (6,000&nbsp;lb), the [[Martin B-26 Marauder]] up to 1,814&nbsp;kg (4,000&nbsp;lb), and the [[Douglas A-20 Havoc]] up to 907&nbsp;kg (2,000&nbsp;lb), for example, but they rarely carried a maximum load; when they did, their range was reduced significantly. Japanese aircraft almost invariably had greater range with their rated maximum load; this gave them a strategic capability unlike that of Allied twin-engine bombers, which were considered tactical bombers.{{Cn|date=December 2023|reason=Disregards Wellington, and other large twin engine mediums}} The Ki-67's performance was remarkable compared to US medium bombers; the Ki-67 had a level-flight top speed of {{convert|537|km/h|abbr=on}} - against {{convert|443|km/h|abbr=on}} for the B-25, 462&nbsp;km/h (287&nbsp;mph) for the B-26, and 538&nbsp;km/h (338&nbsp;mph) for the A-20 -, good manoeuvrability in high-speed dives (up to 644&nbsp;km/h/400&nbsp;mph), excellent sustained rate of climb, and outstanding agility (excellent turn rate, small turn radius, and ability to turn at low speeds{{Cn|date=December 2023}}). The manoeuvrability of the Ki-67 was so good that the Japanese used the design as the basis for the Mitsubishi Ki-109 twin-engine fighter, originally designed as a [[night fighter]], and later for use as a daylight [[heavy fighter]]. In the last stages of World War II, the Japanese Navy also used the design as the basis for the [[Mitsubishi Q2M]]1 "''Tai'yō''" [[radar]]-equipped [[Anti-submarine warfare|anti-submarine aircraft]].{{Citation needed|date=January 2021}}

Armament of the Ki-67 included a dorsal [[Gun turret|turret]] with a [[20 mm caliber|20 mm (.79 in)]] [[Ho-5 cannon]], in addition to [[12 mm caliber|12.7 mm (.50 in)]] [[Ho-103 machine gun]]s in the tail, nose, and beam positions. Some aircraft were fitted with a 20&nbsp;mm gun in the tail position, and early models used [[7.7×58mm Arisaka|7.7 mm (.303in)]] [[Type 89 machine gun]]s in the beam positions.{{Citation needed|date=January 2021}}

==Operations==
[[File:Mitsubishi Ki-67-2.jpg|thumb|right|Ki-67 ''74-148'' of the 74th Hikō Sentai. ([[Matsumoto, Nagano|Matsumoto airfield]], Japan, 1945.)]]

The Ki-67 was used for level bombing and [[Torpedo bomber|torpedo bombing]]; it could carry one [[torpedo]] attached under the fuselage. The Ki-67 was initially used by the Japanese Army and Navy Air Services against the [[United States Third Fleet|US Third Fleet]], during its strikes against [[Taiwan|Formosa]] and the [[Ryukyu Islands]]. It was later used at [[Okinawa Island|Okinawa]], in [[Mainland China]], [[French Indochina]], [[Karafuto]], and [[Japanese air attacks on the Mariana Islands|against B-29 airfields]] in [[Saipan]] and [[Tinian]]. One special [[Ground-attack aircraft|ground-strike]] version used in the ''Giretsu'' missions was a Ki-67 I with three remote-control 20&nbsp;mm cannons angled at 30° for firing toward the ground, a 20&nbsp;mm cannon in the tail, 13.2&nbsp;mm (.51&nbsp;in) [[Type 3 aircraft machine gun|Type 3 machine gun]]s in the [[Anatomical_terms_of_location#Medial_and_lateral|lateral]] and upper positions, and more fuel capacity. Even with more fuel, the ''Giretsu'' missions were one-way only because of the long range. In the last stages of World War II, special attack versions of the Ki-67 (the I Kai and Sakura-dan models) were used in [[kamikaze]] missions. (References include information from Lt. Sgt. Seiji Moriyama, a crew member in ''Fugaku'' Special Attack Unit, who witnessed Ki-67's being converted into ''To-Gō'' suicide planes with two 800&nbsp;kg/1,760&nbsp;lb bombs during Okinawa operations.){{Citation needed|date=January 2021}}

By the end of World War II, 767 Ki-67s had been produced. Other sources relate that 698 Ki-67's were manufactured, excluding the ''Kai'' and ''Sakura-dan'' conversions.{{Citation needed|date=January 2021}}

==Variants==
{{More citations needed section|date=January 2021}}
[[File:Mitsubishi Ki-109.jpg|thumb|right|Ki-109]]
* '''Ki-67-I''': Prototypes. Diverse models with various types of weapons. 19 produced.
* '''Ki-67-Ia "Hiryū" Army Type 4 Heavy Bomber Model 1''': Main production model. The majority (420+) were modified in the factory as land-based [[torpedo bomber]]s (after work-number 160). Produced by Mitsubishi: 587; by Kawasaki: 91; by 1° Army Arsenal of Tachikawa: 1.
* '''Ki-67-Ib''': Late production model. Reinforced the tail gun turret (2 × 20&nbsp;mm).
* '''Ki-67-I Kai''': Experimental model equipped with Mitsubishi Ha-104 Ru engines. 3 produced.
* '''Ki-67-I [[Airborne early warning and control|AEW]] variant''': Equipment the early warning radar "Taki 1 Model II". 1 produced.
* '''Ki-67 "To-Gō"''': Army special attack aircraft type 4: Improved version of the Ki-67 I for ''kamikaze'', unarmed, without turrets, and with two 800&nbsp;kg (1,760&nbsp;lb) bombs in belly compartment.
* '''Ki-67 "guided missile mother ship"''': Experimental type for carrying guided missiles.(Kawasaki Ki-147 I-Go Type 1-Ko, Mitsubishi Ki-148 I-Go Type 1-Otsu, I-Go Type 1-Hei, "Ke-Go" IR, "Ko-Go","Sa-Go") 1 produced.
* '''Ki-67 long-range bomber variant''': Equipped with widened wings and without turrets. Only a project.
* '''Ki-67 ground attack variant''': Version armed with three remote-control ground-firing 5 × 30° 20&nbsp;mm cannons, 20&nbsp;mm defensive cannon in the tail position, three 13.2&nbsp;mm (.51&nbsp;in) machine guns in lateral and upper positions, and more fuel capacity for long range. Specifically designed for land strikes against B-29 bases in the Marianas. Only a project.
* '''Ki-67-II''': Prototypes. Modified version of the Ki-67-I, with two Mitsubishi Ha-214 engines of {{cvt|2150|hp-metric|kW|0|disp=flip}} each. 2 produced.
*'''Ki-67 glider tug''': A standard Ki67-I was used to tow the "Manazuru" (Crane) transport glider in tests.
* '''"Yasukuni"''':  Naval torpedo bomber version of the Ki-67-I. Created from Ki-67-Is transferred from the IJAAF.
* '''Ki-69''': Heavily armed escort fighter model. Only a project.
* '''Ki-97''': Transport model. Only a project.
* '''Ki-109''': Night fighter prototypes. Ki-67-I modified for night fighting for operating in pairs, the Ki-109a with a [[radar]]/reflector (similar to the British [[Douglas A-20 Havoc|Douglas Havoc]] II "[[Turbinlite]]" concept, only using radio beams rather than a powerful searchlight) for radar transmission and detection and the Ki-109b, armed with twin 37&nbsp;mm [[Ho-203 cannon]] in an upward-firing ''[[Schrage Musik]]''-style fixed dorsal mount (as the single Ho-203 autocannon in the [[Mitsubishi Ki-46]]-III Kai was) to destroy the objective. Only a project.
* '''Ki-109''': Day Fighter prototypes. Ki-67-I modified for daylight fighting. One fixed [[Type 88 75 mm AA gun|75&nbsp;mm Type 88 Heavy Cannon]] in the nose and one mobile 12.7&nbsp;mm (0.5&nbsp;in) Ho-103 Type 1 machine gun in the tail. Equipped with Mitsubishi Ha-104 engines of 1,417&nbsp;kW (1,900&nbsp;hp) each or [[turbocharged]] Ha-104 Ru with 1,417&nbsp;kW (1,900&nbsp;hp) each. 2 produced.
* '''Ki-109 Army Heavy Fighter Interceptor''': First non-prototype model of series. Lacking gun positions in upper and side positions and without bomb-bay compartments{{citation needed|reason=Faired positions are well documented, but I could find no reliable source on deletion of the bomb bay.|date=May 2015}}. Fixed 75&nbsp;mm Type 88 Heavy Cannon in the nose retained from Day Fighter prototype. Had a revised version of tail gun. 22 constructed by Mitsubishi.
* '''Ki-112''': Bomber escort fighter made with a wooden construction. Armed with 8 x 12.7mm and 1 x 20mm. Only a project.
* '''Ki-167 "Sakura-dan"''': "[[Kamikaze|Special Attack]]" (kamikaze) version equipped with one [[shaped charge]] thermite bomb of 2,900&nbsp;kg (6,400&nbsp;lb) in the fuselage behind the crew cabin. The shape of the bomb conducted the blast forward, projecting a jet capable of reaching nearly a mile with a maximum blast radius of 300&nbsp;m (980&nbsp;ft). The bomb was designed to breach emplacements as well as to destroy massed formations of armor. 9 produced.<ref>{{harvnb|Hayashi|2005|p=100}}</ref>
* '''[[Mitsubishi Q2M|Q2M1 ''Tai'yō'']]''': Navy variant of Ki-67-I, for anti-submarine warfare. Equipped with radar (Type3 Model 1 MAD (KMX), Type 3 Ku-6 Model 4 Radar, and ESM Antenna equipment). Had two Mitsubishi Kasei 25 ''Otsu'' engines of {{cvt|1380|kW}} each with six-blade propellers. Carried torpedoes or [[depth charge]]s. Project only.

==Operators==
{{Unreferenced section|date=January 2021}}

===Wartime===
;{{JPN}}
*[[Imperial Japanese Army Air Service]]
**Hamamatsu Instructing Flying Division
**7th Hikō Sentai
**14th Hikō Sentai
**60th Hikō Sentai
**61st Hikō Sentai
**62nd Hikō Sentai
**74th Hikō Sentai
**110th Hikō Sentai
**170th Bombardment Group (ex-60th Hikō Sentai and 110th Hikō Sentai)
*[[Imperial Japanese Navy Air Service]]
**11th Air Flotilla

==Specifications (Ki-67-Ib)==
[[File:War booty Ki-67.jpg|thumb|right|A captured Ki-67]]
{{Aircraft specs
|ref= Japanese Aircraft of the Pacific War<ref name="Frnc70p191">{{Harvnb|Francillon|1970|p=103}}</ref>
|prime units?=met
<!--
        General characteristics
-->
|crew=6–8
|length m=18.7
|length note=
|span m=22.5
|span note=
|height m=7.7
|height note=
|wing area sqm=65.85
|wing area note=
|aspect ratio=<!-- sailplanes -->
|airfoil=<!--'''root:''' [[NACA airfoil|NACA ]]; '''tip:''' [[NACA airfoil|NACA ]]<ref name="Selig">{{cite web |last1=Lednicer |first1=David |title=The Incomplete Guide to Airfoil Usage |url=https://m-selig.ae.illinois.edu/ads/aircraft.html |website=m-selig.ae.illinois.edu |accessdate=16 April 2019}}</ref>-->
|empty weight kg=8649
|empty weight note=
|gross weight kg=13765
|gross weight note=
|max takeoff weight kg=
|max takeoff weight note=
|fuel capacity=
|more general=
<!--
        Powerplant
-->
|eng1 number=2
|eng1 name=[[Mitsubishi Ha104]] ("Army Type 4 1,900hp Air Cooled Radial")
|eng1 type=18-cylinder air-cooled radial piston engines
|eng1 kw=<!-- prop engines -->
|eng1 hp=1900
|eng1 shp=<!-- prop engines -->
|eng1 kn=<!-- jet/rocket engines -->
|eng1 lbf=<!-- jet/rocket engines -->
|eng1 note=for take-off{{efn| {{cvt|1810|hp|order=flip}} at {{cvt|2200|m}}, {{cvt|1610|hp|order=flip}} at {{cvt|6100|m}} }}

|prop blade number=4
|prop name=constant-speed metal propellers
|prop dia m=<!-- propeller aircraft -->
|prop dia note=
<!--
        Performance
-->
|max speed kmh=537
|max speed note=at {{cvt|6090|m}}
|cruise speed kmh=400
|cruise speed note=at {{cvt|8000|m}}
|stall speed kmh=
|stall speed note=
|never exceed speed kmh=
|never exceed speed note=
|minimum control speed kmh=
|minimum control speed note=
|range km=2800
|range note=
|combat range km=
|combat range note=
|ferry range km=3800
|ferry range note=
|endurance=<!-- if range unknown -->
|ceiling m=9470
|ceiling note=
|g limits=<!-- aerobatic -->
|roll rate=<!-- aerobatic -->
|climb rate ms=
|climb rate note=
|time to altitude={{cvt|6000|m}} in 14 minutes 30 seconds
|wing loading kg/m2=209
|wing loading note=
|fuel consumption kg/km=
|power/mass={{cvt|0.125|hp/lb|order=flip}}
|more performance=
<!--
        Armament
-->
|guns=<br>
** 1 × {{convert|20| mm|abbr=on}}  [[Ho-5 cannon]] in dorsal turret
** 5 × 12.7 mm (.50in) [[Ho-103 machine gun|Ho-103 (Type 1) machine guns]], one in nose, 1 in the tail, and 1 in each beam position (late models){{efn|Early models carried magazine-fed 7.7 mm  (.303in) [[Type 89 machine gun]]s in the beam positions.}}
|bombs= 800 kg (1,764 lb) of bombs in internal bay or one torpedo{{efn| Kamikaze versions carried 2,900 kg (6,400 lb) of bombs}}
|avionics=
}}

==See also==
{{aircontent
|related=
* [[Mitsubishi Q2M]]
|similar aircraft=
* [[Yokosuka P1Y]] 
* [[Douglas A-26 Invader]]
* [[Mitsubishi G4M]]
* [[Nakajima Ki-49]] 
* [[Douglas A-20 Havoc]]
* [[Martin B-26 Marauder]]
* [[Petlyakov Pe-2]]
* [[North American B-25 Mitchell]]
* [[Vickers Wellington]]
* [[Tupolev Tu-2]]
* [[Junkers Ju 88]]
* [[Dornier Do 217]]
* [[Heinkel He 111]]
|lists=
* [[List of aircraft of World War II]]
|see also=
}}

==References==
===Notes===
{{notelist}}

===Citations===
{{reflist}}

===Bibliography===
{{Refbegin}}
* Bueschel, Richard M. ''Mitsubishi Ki-67/Ki-109 Hiryu in Japanese Army Air Force Service''. Atglen, PA: Schiffer Publishing, Ltd., 1997. {{ISBN|0-7643-0350-3}}.
* {{cite book |last=Francillon |first=René J. |title=Japanese Aircraft of the Pacific War |year=1970 |location=London |publisher=Putnam and Company Ltd |isbn=0-370-00033-1}} 
* Francillon, René J. ''Japanese Aircraft of the Pacific War''. Annapolis, MD: Naval Institute Press, 1995 (reprint).
* Green, William. ''Famous Bombers of the Second World War''. London: MacDonald & [[Jane's]] (Publishers) Ltd., 1975 (2nd Edition). {{ISBN|0-356-08333-0}}.
* Green, William. ''Warplanes of the Second World War, Volume Three: Fighters''. London: Macdonald & Co. (Publishers) Ltd., 1961 (seventh impression 1973). {{ISBN|0-356-01447-9}}. (On the Ki-109 Fighter version)
* {{cite magazine |title=Masterpiece to Manned Missile...Mitsubishi's Final Bomber |magazine=[[Air International]] |date= July 1983 |volume=25 |issue=1 |pages=25–33, 47 |issn= 0306-5634 |ref={{harvid|''Air International'' July 1983}}}}
* {{cite book |last=Hayashi |first=Eidai |title= 重爆特攻さくら弾機 |trans-title=Suicide heavy bomber "Sakura-dan"| year=2005 |publisher= Tohoshuppan |location=Osaka, Japan |isbn=978-488591955-8 |language=Japanese}}
{{Refend}}

==External links==
{{Commons category|Mitsubishi Ki-67}}
*[https://web.archive.org/web/20060822090107/http://www.ijaafpics.com/jbwki671.htm Rod's WarBirds – Many WWII pictures of the Ki-67.]
*[https://ndlonline.ndl.go.jp/#!/detail/R300000001-I000007745053-00 Technical Air Intelligence Center Summary No. 26: Peggy I]

{{Mitsubishi aircraft}}
{{Japanese Army Aircraft Designation System}}
{{Imperial Japanese Army aircraft names}}
{{Japanese Navy short aircraft designations}}
{{Allied reporting names}}
{{Authority control}}

[[Category:Mitsubishi aircraft|Ki-67]]
[[Category:1940s Japanese bomber aircraft|Ki-67, Mitsubishi]]
[[Category:Mid-wing aircraft]]
[[Category:Aircraft first flown in 1942]]
[[Category:Twin piston-engined tractor aircraft]]
[[Category:Aircraft with retractable conventional landing gear]]