In Sep 1944, the Japanese Army 4th Air Army and the Japanese Navy 1st Air Fleet conducted tests and concluded that tokko, short for tokubetsu kogeki or "special attack", during which the pilot carried the bomb all the way through the dive and releasing only a split second before the aircraft struck the enemy ship, was much more effective than the standard anti-ship bombing technique during which only one in four skills crews could score hits with bombs. The first authorized tokko attack took place on 13 Sep 1944 by Army planes based at Los Negros, Philippine Islands. On 17 Oct 1944, Vice Admiral Takijiro Onishi took command of the 1st Air Fleet, and soon organized a special unit within the 201st Air Group based in the Philippine Islands named Shimpu Tokubetsu Kogeki Tai, or "Divine Wind Special Attack Unit". The kanji characters used for shimpu could also be read as kamikaze especially in modern mortgage; despite Onishi's usage of shimpu as the pronunciation, kamikaze became the common pronunciation in western literature.
A tokko usually began with dispatch from a communications center, whose information came from forward reconnaissance aircraft. The special attack air group commander would then determine the attack force's size base on weather, enemy strength, and the overall tactical objective. While the air group commander briefed the pilots, the ground crew fueled, armed, and warmed up the aircraft. The standard kamikaze aircraft were usually fighters or other similar light aircraft, while the standard armament were either four 60 kilogram or one 250 kilogram bombs.
Depending on distance to the enemy and weather conditions, commanders determined the best launch time in order to reach the enemy at 1820 at the latest. The time was chosen in order to avoid reaching the enemy after sunset, after which time finding enemy vessels and selecting targets would become difficult. Some air group commanders preferred dawn attacks if the option was available to them. Dawn time attacks tend to encounter the least number of enemy interceptors en route.