The first book I read about Midway, many years ago, described the B5N as carrying three 550lb bombs. That's within its payload, but I've never seen that specific loadout referenced anywhere else. It might be a useful load for high-level bombing, maybe more so than the one big bomb - 800kg - that Shattered Sword credits them with carrying at Midway. Has anyone else seen this?
Since Shattered Sword took a lot of IJN documents into account that many earlier books didn't I tend to give them the edge there even if I wasn't so impressed with them. I think I've seen some posting over on j-aircraft on the topic or something similar as well and from what I recall the single bomb seems to be the most likely at least for naval targets.
The weight was within it's maximum payload, however, the bomb shackles were not designed to carry that particular loadout. Also, I have never seen that mentioned as a load out for either the B5N or B6N. It probably had to do with the ground clearance of the fins of the last bomb.
Alan Zimm, Attack on Pearl Harbor: Strategy, Combat, Myths, Deceptions pg. 59. Page 59: :The "heavy hitter": wa the B5N Kat, an aircraft with a crew of three that could be used either as a high-altitude level bomber or a torpedo bomber; payload options were one 250 kilogram (kg) high explosive general-purpose (GP) bomb and six 60kg GP bombs or two 250kg bombs,[21] one 800kg AP bomb, or one 800kg 18-inch torpedo. [21] The B5N Kate had the lifting capacity for three 200-kg bombs, and this capacity is listed in many references. The possibility exists that at this time the bomber only had hard point attachments for two. (Any mistakes are mine. LWJ)
