Category: Kūgishō
What Was the A6M4?
The A6M4 is an “unknown” variant of the Zero Fighter that has been described as a variety of things over the years. The most common theory in English writing is that A6M4 was a designation for a type of Zero fitted with a turbocharger to its Sakae engine. Another common theory is that the number…
Identifying Japanese Jets Captured by the US in 1945
Following the surrender of Japan in August 1945, the American occupational authorities sought to gather whatever aircraft developments were of potential interest. Naturally, the most cutting edge planes and engines developed in Japan were high on this list. More than a few of these projects had already been destroyed by Japanese orders immediately issued to…
Ōka Trainers: MXY7-K1, MXY7-K2, & Wakazakura
This article is an attempt to clarify the details of the different training aircraft that were developed for the Japanese Navy’s late-war special attacker ‘Ōka’. The designations and purposes of the Ōka trainers are often confused, not only in English but even in Japanese publications. Using a few historical materials, we can correctly identify them…
R2Y Keiun: Satisfactory… but the Engine Caught on Fire
At the outset of the Second Sino-Japanese War in 1937, the Japanese Navy’s Air Service assumed a leading role in the strategic bombardment of China with their modern force of attack planes. As the battle quickly advanced into the interior of the continent, the Navy developed a new requirement to maintain force projection: the need…
Tanegashima’s Group: Birth of the Japanese Jet Engine
By the 1930s, the practical speed limit of piston-engined aircraft was being approached for the first time. Before a propeller-driven airplane can approach the speed of sound, there is a period where the blade tips must reach supersonic speed, resulting in massive turbulence and loss of efficiency. This effect imposes a rough ‘limit’ on the…
