The carrier-based attack bomber Nakajima B5N2 was given the code name Kate by Americans. It was a development of the B5N1 that saw service in the war with China. It was vulnerable to enemy fighters, being armed only with a .303 (7.7mm) machine-gun, and thus needed a fighter escort. The B5N2 was not much improved, a new engine providing little additional speed. The engine was the 1,000-hp Nakajima NK1B Sakae 11 14-cylinder radial piston engine. The Kate had a cruising speed of 161 mph and a top speed of 235 mph. The range was 1,237 miles. Kates could carry an 18-inch torpedo or a 500kg bomb. They were the spearhead of the force that attacked Pearl Harbor from the First Air Fleet.
You can find out more about Kates in the following Osprey books: