The Mitsubishi B5M was an

Imperial Japanese Navy Air Service The was the Naval aviation, air arm of the Imperial Japanese Navy (IJN). The organization was responsible for the operation of naval aircraft and the conduct of aerial warfare in the Pacific War. The Japanese military acquired their first air ...

(IJNAS) land-based

attack aircraft An attack aircraft, strike aircraft, or attack bomber is a tactical military aircraft that has a primary role of carrying out airstrikes with greater precision than bombers, and is prepared to encounter strong low-level air defenses while pre ...

, originally intended for carrier use. The B5M was also given the long formal designation and Allied reporting name of Mabel. The B5M was designed in response to a 1935 specification for a new

bomber A bomber is a military combat aircraft designed to attack ground and naval targets by dropping air-to-ground weaponry (such as bombs), launching aerial torpedo, torpedoes, or deploying air-launched cruise missiles. The first use of bombs dropped ...

for use on the IJNAS

aircraft carrier An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and facilities for carrying, arming, deploying, and recovering aircraft. Typically, it is the capital ship of a fleet, as it allows a ...

s (Mitsubishi Navy Experimental 10-Shi Carrier Torpedo Attacker). The machine was to have a crew of three,

folding wing A folding wing is a wing configuration design feature of aircraft to save space and is typical of carrier-based aircraft that operate from the limited deck space of aircraft carriers. The folding allows the aircraft to occupy less space in a c ...

s for flight deck storage, a speed of not less than 322 km/h (200 mph), a flight endurance of not less than seven hours, and the ability to carry at least 800 kg (1,760 lb) of bombs - a tall order for a single-engine aircraft of the mid-1930s. It was intended as a backup for the

Nakajima B5N The Nakajima B5N ( ja, 中島 B5N, Allied reporting name "Kate") was the standard carrier-based torpedo bomber of the Imperial Japanese Navy (IJN) for much of World War II. Although the B5N was substantially faster and more capable than its Al ...

"Kate"

torpedo bomber A torpedo bomber is a military aircraft designed primarily to attack ships with aerial torpedoes. Torpedo bombers came into existence just before the First World War almost as soon as aircraft were built that were capable of carrying the weight ...

. Although designed as a carrier-based aircraft, it was relegated to land-based torpedo bomber duties in

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...

. 125 were built.

Operational history

The aircraft that Mitsubishi produced first flew in 1937 and was an all-metal, low-wing

cantilever A cantilever is a rigid structural element that extends horizontally and is supported at only one end. Typically it extends from a flat vertical surface such as a wall, to which it must be firmly attached. Like other structural elements, a canti ...

monoplane A monoplane is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplanes, which have multiple planes. A monoplane has inherently the highest efficiency and lowest drag of any wing confi ...

with fixed

undercarriage Undercarriage is the part of a moving vehicle that is underneath the main body of the vehicle. The term originally applied to this part of a horse-drawn carriage, and usage has since broadened to include: *The landing gear of an aircraft. *The ch ...

with large wheel spats. The crew of three sat in a long

canopy Canopy may refer to: Plants * Canopy (biology), aboveground portion of plant community or crop (including forests) * Canopy (grape), aboveground portion of grapes Religion and ceremonies * Baldachin or canopy of state, typically placed over an a ...

that had a smooth transition to the

fuselage The fuselage (; from the French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds crew, passengers, or cargo. In single-engine aircraft, it will usually contain an engine as well, although in some amphibious aircraft t ...

. The B5M1s began equipping Japanese Naval units in late 1937, but their performance was never as satisfactory as was that of other Japanese aircraft carrier-based bombers. The B5M1's performance was considered marginal and only 125 were manufactured. While they had originally been intended for aircraft carrier use, the majority were employed during the early months of World War II from land bases in Southeast Asia and in China, where they were confronted by weak or no enemy fighter opposition. These machines ended their careers as trainers,

target tug A target tug is an aircraft which tows an unmanned drone, a fabric drogue or other kind of target, for the purposes of gun or missile target practice. Target tugs are often conversions of transport and utility aircraft, as well as obsolescent comb ...

s, and ''

kamikaze , officially , were a part of the Japanese Special Attack Units of military aviators who flew suicide attacks for the Empire of Japan against Allied naval vessels in the closing stages of the Pacific campaign of World War II, intending to d ...

s''.

Variants

*B5M1:Three-seat attack aircraft for the

Imperial Japanese Navy The Imperial Japanese Navy (IJN; Kyūjitai: Shinjitai: ' 'Navy of the Greater Japanese Empire', or ''Nippon Kaigun'', 'Japanese Navy') was the navy of the Empire of Japan from 1868 to 1945, when it was dissolved following Japan's surrender ...

Operators

; *

Specifications (Mitsubishi B5M1)

References

Bibliography