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Aichi B7A Ryusei (Grace)

Imperial Japan (1944)

Detailing the development and operational history of the Aichi B7A Ryusei (Grace) Torpedo Bomber / Dive Bomber.

 Entry last updated on 4/11/2018; Authored by Staff Writer; Content ©

  Aichi B7A Ryusei (Grace)  
Picture of Aichi B7A Ryusei (Grace) Torpedo Bomber / Dive Bomber

By the time the Aichi B7A series made it to operational status, Japan no longer had her aircraft carriers.

The Aichi-produced B7A "Ryusei" (translated to "Shooting Star" and nicknamed "Grace" by the Allies) was a limited-production torpedo/dive bomber in service with the Imperial Japanese Navy (IJN) during the late stages of World War 2. Unfortunately for the design, the aircraft arrived too late to be fielded in force as the Japanese Navy was now without any viable carrier options by the time of the B7A's adoption. With just a scant 114 production aircraft resulting, the series became an overlooked Aichi wartime design that would never have a chance to live up to its perceived potential as a new, all-modern carrier-based torpedo/dive bombing platform.

The B7A Ryusei was conceived of to fulfill a new Japanese Navy requirement for a carrier-based torpedo/dive bomber as early as 1941. A prototype was flown during 1942 but the aircraft, seeing prolonged delays from engine development issues and natural causes (an earthquake on the island), was forced to await receiving its official operational status until 1944. By then, the Japanese Navy was all but crippled of her strategic, and vastly important, aircraft carriers across the Pacific Theater that the B7A would instead see limited-duty from land-based airfields.

At its core, the Aichi B7A Ryusei was a single engined, two-seat, low monoplane aircraft design. A dorsal arrangement allowed for the carrying of a single 1,764lb torpedo or an equal amount of standard drop ordnance. Additionally, two forward-firing, fixed 20mm cannons were mounted in the leading wing edges while a single, defensive-minded, 7.92mm or 13mm machine gun was fitted to a flexible mounting at the rear cockpit position for added defense.
Power was served through a Nakajima NK9C Homare 12 model, 18-cylinder, air-cooled, radial piston engine of 1,825 horsepower providing for a top speed of 352 miles per hour, a range out to 1,890 miles and a service ceiling up to 36,910 feet. The engine drove a four-bladed propeller assembly.

Dimensions included a length of 37 feet, 8 inches, a wingspan of 47 feet, 3 inches, and a height of 13 feet, 5 inches. As the B7A was intended for carrier service, it came complete with hinged wing sections to allow for folding on space-strapped aircraft carriers of the IJN.

Prototypes were recognized as B7A1 and a total of nine were produced. The B7A2 designation marked production quality bombers for the IJN to which 105 examples emerged. One model served as an experimental product fitting the Nakajima Homare 23 series engine. The B7A3 designation was a proposed mark outfitted with the Mitsubishi MK9A (Ha-43) engine - none of this mark were constructed.
Aichi B7A Ryusei (Grace) Specifications
National Flag Graphic
Imperial Japan
Year: 1944
Status: Retired, Out-of-Service
Type: Torpedo Bomber / Dive Bomber
Manufacturer(s): Aichi Kokuki KK - Japan
Production: 114
Supported Mission Types
Ground Attack
Close-Air Support
Airborne Early Warning
Electronic Warfare
Aerial Tanker
Passenger Industry
VIP Travel
Business Travel
Special Forces
Crew: 2
Length: 37.73 ft (11.5 m)
Width: 47.24 ft (14.40 m)
Height: 13.35 ft (4.07 m)
Empty Weight: 8,378 lb (3,800 kg)
MTOW: 14,330 lb (6,500 kg)

Installed Power
1 x Nakajima NK9C Homare 12 series 18-cylinder radial engine developing 2,000 horsepower.

Standard Day Performance
Maximum Speed: 351 mph (565 kph; 305 kts)
Maximum Range: 1,889 mi (3,040 km; 1,641 nm)
Service Ceiling: 36,909 ft (11,250 m; 6.99 mi)
Rate-of-Climb: 1,890 ft/min (576 m/min)

2 x 20mm Type 99 cannons in wings
1 x 7,92mm Type 1 OR 13mm Type 2 machine gun in rear cockpit position.

Up to 1,765lbs of drop ordnance including 1 x "Long Lance" torpedo.

Operators List
Imperial Japan

Series Model Variants
• B7A "Ryusei" - Base Series Designation
• B7A1 - Prototype designation; nine examples completed.
• B7A2 - IJN production bomber designation
• B7A2X - Experimental mount fitted with Nakajima Jomare 23 series radial piston engine of 1,490 horsepower; single example of B7A2 model.
• B7A3 - Proposed variant fitting Mitsubishi MK9A engine of 2,200 horsepower; not produced.

Supported Weapon Systems
Graphical image of an aircraft medium machine gun
Graphical image of an aircrat automatic cannon
Graphical image of an aircraft aerial torpedo
Graphical image of an aircraft conventional drop bomb munition