Aviation & Aerospace - Airpower 2024 - Aircraft by Country - Aircraft Manufacturers Vehicles & Artillery - Armor 2024 - Armor by Country - Armor Manufacturers Infantry Small Arms - Warfighter 2024 - Small Arms by Country - Arms Manufacturers Warships & Submarines - Navies 2024 - Ships by Country - Shipbuilders U.S. Military Pay 2024 Military Ranks Special Forces by Country

Kawasaki Ki-91

Heavy Bomber Aircraft Proposal

Imperial Japan | 1945

"An Allied air raid during early 1945 ended development of the Kawasaki Ki-91 four-engined heavy bomber for Japan."

Authored By: Staff Writer | Last Edited: 06/18/2021 | Content ©www.MilitaryFactory.com | The following text is exclusive to this site; No A.I. was used in the generation of this content.
The Kawasaki Ki-91 represented a rare four-engine heavy bomber initiative of the middle-to-late war years for the Japanese Empire. The Ki-91 gained steam at a time when the Japanese military was reeling from consistent losses in-the-field and air supremacy was being lost on a month-to-month basis. It would seem prudent that fighters and interceptors would be the call of the day as it became in Germany but this four-engined "heavy" was still pushed through by Kawasaki.

The design was to feature a wingspan reaching 157.4 feet with a length of 108.2 feet - dimensionally larger than even the famous American Boeing B-29 "Superfortress" (141.2 foot wingspan, 99 foot length). Loaded weight was estimated at 127,870 pounds. The bombload was to be in the 8,820 lb range (decidedly less than the Superfortress' 20,000lb load limit) and the aircraft defensed by no fewer than 12 x 20mm cannons - two fitted to a nose turret, two in a dorsal turret, four across two ventral turrets (one forward, the other aft), and four to complete a turret at the tail - one of the best-armed bombers of the war to say the least. The large aircraft would be powered by 4 x Mitsubishi Ha-214 "Ru" engines developing upwards of 2,500 horsepower each and estimated performance specs included a maximum speed of 360 miles per hour with a ferry range out to 6,215 miles (the B-29 managed a speed of 360mph with a ferry range out to 5,600 miles).

Outwardly, the aircraft was to be given a stepped cockpit approach meaning the flight deck sat out from the fuselage contours and held its own window panels (unlike the streamlined form of the B-29). The fuselage would be a rounded rectangle in profile with slab sides, the shape broken up some by the placement of several observation bubbles about her design. Glazing would be featured at the nose and around the cockpit with vision ports located throughout the rest of the fuselage and at gun positions. Mid-mounted monoplane wings were used, each featuring a pair of engine nacelles along their leading edges. The tail unit would consist of a single, rounded vertical fin coupled to a pair of low-mounted horizontal planes - these surfaces seated ahead of the tail turret. A tricycle undercarriage would be employed which was a departure of the "Tail dragger" configuration of old.

Design work on the aircraft began in May of 1943 and progress was such that by the end of 1944 the first prototype was being built while Kawasaki lines were gearing up for serial production. However, an Allied bombing raid during February 1945 destroyed much of what was to make the Ki-91 possible, forcing the program to be halted and ultimately abandoned in favor of fighters and interceptors to contend with the American B-29 presence over the Japanese homeland.

Content ©MilitaryFactory.com; No Reproduction Permitted.
Power & Performance
Those special qualities that separate one aircraft design from another. Performance specifications presented assume optimal operating conditions for the Kawasaki Ki-91 Heavy Bomber Aircraft Proposal.
4 x Mitsubishi Ha-214 Ru engines developing 2,500 horsepower each.
360 mph
580 kph | 313 kts
Max Speed
The nose-to-tail, wingtip-to-wingtip physical qualities of the Kawasaki Ki-91 Heavy Bomber Aircraft Proposal.
107.9 ft
32.90 m
O/A Length
157.4 ft
(47.97 m)
O/A Width
128,000 lb
(58,060 kg)
Available supported armament and special-mission equipment featured in the design of the Kawasaki Ki-91 Heavy Bomber Aircraft Proposal .
2 x 20mm in nose
2 x 20mm cannons in dorsal turret
2 x 20mm cannons in forward ventral turret
2 x 20mm cannons in aft ventral turret
4 x 20mm cannons in tail turret

A bomb load of up to 8,820 pounds held internally.
Notable series variants as part of the Kawasaki Ki-91 family line.
Ki-91 - Base Series Designation; prototype destroyed in Allied air raid during February of 1945.
Global customers who have evaluated and/or operated the Kawasaki Ki-91. Nations are displayed by flag, each linked to their respective national aircraft listing.

Total Production: 0 Units

Contractor(s): Kawasaki - Imperial Japan
National flag of modern Japan

[ Imperial Japan (cancelled) ]
Relative Max Speed
Hi: 400mph
Lo: 200mph
Aircraft Max Listed Speed (360mph).

Graph Average of 300 MPH.
Era Crossover
Pie graph section
Showcasing Aircraft Era Crossover (if any)
MACH Regime (Sonic)
RANGES (MPH) Subsonic: <614mph | Transonic: 614-921 | Supersonic: 921-3836 | Hypersonic: 3836-7673 | Hi-Hypersonic: 7673-19180 | Reentry: >19030
Aviation Timeline
1 / 1
Image of the Kawasaki Ki-91
Image copyright www.MilitaryFactory.com; No Reproduction Permitted.

Mission Roles
Some designs are single-minded in their approach while others offer a more versatile solution to airborne requirements.
Some designs stand the test of time while others are doomed to never advance beyond the drawing board; let history be their judge.
Going Further...
The Kawasaki Ki-91 Heavy Bomber Aircraft Proposal appears in the following collections:
Disclaimer | Privacy Policy | Cookies

2024 Military Pay Scale Military Ranks U.S. DoD Dictionary Conversion Calculators Military Alphabet Code Military Map Symbols US 5-Star Generals WW2 Weapons by Country

The "Military Factory" name and MilitaryFactory.com logo are registered ® U.S. trademarks protected by all applicable domestic and international intellectual property laws. All written content, illustrations, and photography are unique to this website (unless where indicated) and not for reuse/reproduction in any form. Material presented throughout this website is for historical and entertainment value only and should not to be construed as usable for hardware restoration, maintenance, or general operation. We do not sell any of the items showcased on this site. Please direct all other inquiries to militaryfactory AT gmail.com. No A.I. was used in the generation of this content.

Part of a network of sites that includes Global Firepower, WDMMA.org, WDMMW.org, and World War Next.

©2024 www.MilitaryFactory.com • All Rights Reserved • Content ©2003-2024 (21yrs)