Nakajima B5N

Nakajima B5N2
Description
Role	Torpedo bomber
Crew	3
First Flight	January 1937 (B5N1)
Entered Service	1937
Manufacturers	Nakajima, Aichi, Dai-Juichi
Dimensions
Length	10.30m	33' 9"
Wingspan	15.52m	50' 11"
Height	3.70m	12' 2"
Wing area	37.7m²	405 ft²
Weights
Empty	2,279kg	5,014 lbs
Loaded	3,800kg	8,360 lbs
Maximum takeoff	4,100kg	9,020 lbs
Powerplant
Engines	1x Nakajima Sakai 11
Power	746kW	1,000 hp
Performance
Maximum speed	367km/h	229 mph
Range	1,935km	1,209 miles
Service ceiling	8,260m	27,092 ft
Rate of climb	391m/min	1,282 ft/min
Wing loading	101kg/m²	21 lb/ft²
Power/Mass	0.20kW/kg	0.12 hp/lb
Avionics
Armament
Guns	1x 7.7mm Type 92 machine gun tail gun
Stores	1x 800kg (1,760 lb) torpedo or 3x 250kg (550 lb) bombs

The Nakajima B5N (Japanese: 中島 B5N, Allied reporting name: Kate) was the Imperial Japanese Navy's standard torpedo bomber for the first years of World War II. Although, like its Allied counterparts the TBD Devastator and Fairey Swordfish, the type was obsolescent by 1939, B5Ns were flown nearly throughout the whole war. Although primarily used as a carrier-based aircraft, it was also used as a land-based bomber on occasions.

The B5N was designed by a team led by Katsuji Nakamura in response to a 1935 specification by the Navy for a torpedo bomber to replace the Yokosuka B4Y. Internally designated Type K by Nakajima, it successfully competed with the Mitsubishi B5M for a production contract. The first prototype flew in January 1937 and was ordered into production soon afterwards with the full designation Type 97 Carrier Attack Bomber.

It would not be long until the B5N would see combat, first in the Sino-Japanese War, where combat experience revealed several weaknesses in the original B5N1 production model. These were mainly concerned with the lack of protection that the design offered its crew and fuel tanks. Keen to maintain the high performance of the type, the Navy was reluctant to add weight in the form of armour, and instead looked to obtaining a faster version of the aircraft in the hopes of out-running enemy fighters. The B5N2 was given a much more powerful engine, and various modifications were made to streamline it. Although its performance was only marginally better, and its weaknesses remained untreated, this version replaced the B5N1 in production and service from 1939. It was this version that would be used by the Navy in the attack on Pearl Harbor. Apart from this raid, the greatest successes of the B5N2 were the key roles they played in sinking the US Navy aircraft carriers Yorktown, Lexington, Wasp, and Hornet.

The B5N served as the basis for a follow-on design, the Nakajima B6N, which eventually replaced it in front-line service. Subsequently, the B5N continued to fly in secondary roles, such as training, target towing, and anti-submarine warfare. Some of the aircraft used for this latter purpose were equipped with early radars and magnetic anomaly detectors. B5Ns were also used as bombers during the unsuccessful defence of the Philippines in October 1944.

Altogether, around 1,150 were built, of which not a single complete example exists today. A large part of a B5N2 was recovered from the Kuril Islands by a British private collector in 2003.

Related content
Related Development Nakajima B6N
Similar Aircraft	TBD Devastator
Designation Series	B2M - B3Y - B4Y - B5M/B5N - B6N - B7A
Related Lists	List of military aircraft of Japan - List of torpedo bombers

List of Aircraft | Aircraft Manufacturers | Aircraft Engines | Aircraft Engine Manufacturers Airlines | Air Forces | Aircraft Weapons | Missiles | Years in Aviation