History Brief
The Nakajima B6N1 Type 11 attack/torpedo bomber Tenzan, Allied code name “Jill”, was introduced in 1943 as a replacement for the B5N Kate. It was a big improvement over the Kate and, although faster and more maneuverable, it was still no match for the U.S. Navy’s carrier-based fighters. The losses were so great that only one Jill is known to be in existence today.
There were two main production variants of the Jill – the earlier Type 11 and the later Type 12. The Type 11 had the more powerful Mamori Model 11 power plant, a 14-cylinder radial (rated 1870 hp at takeoff), but it proved to be unreliable. The Mamori engine was dropped in favor of the more dependable but considerably weaker Kasei powerplant in the Tenzan Type 12 design.
