[gian paolo]

From Osamu Tagaya : Imperial Japanese Naval Aviator 1937-45 :

" Yokosuka Kokutai experimented with these formations during the latter


half of 1942 , and limited use was made of them in combat during the

first half of 1943 ......... It was first adopted on a regular bases by

204 Kokutai from the beginning of June 1943 over the Solomon Islands .


Other units followed , and by the end of the year, it had replaced

the three-plane shotai as the standard fighter formation of the IJN ."


I have no information for the IJAAF , but I guess the time was roughly

the same , a bit earlier perhaps .


Best wishes


gianpaolo