Because they only became Kamakazie (how do you spell that?) afther they ran out of ammunition and the fight was not over. They did not want to killed before they chose to die in an honourable way.
Ahem. First, they didn't wear helmets. They were the standard headsets so they could communicate with fellow pilots.
Second, the literal translation for Kamikaze is 'divine wind', from a time when a huge storm prevented an invasion of Japan. Early in the war, the pilots would crash there planes into Allied resources and the likes if they were damaged or out of ammunition because, like you said, it was an honerable way to die, but later in the war, Japan enlisted whole aircrews who would fly their bomb-laden fighters deliberately into enemy shipping as the Japanese war-effort got more desperate. As resources dimished in Japan, just like Germany and their weird wooden jets, Japan stated designing low-labour, simple aircraft deliberately for the Kamikaze cause.
Modern suicide bomber though, don't typically display the same honor; it's more of a self motivation in that they are psycologically prepeared to die, whilst the people they take with them, are fearful. The Japanese, were taking their own lives, for the greater good of Japan, just like the divine wind.
In our culture, it goes against our concept of modern warfare, which is why we don't fully understand it.
Fixie God; it was dishonerable for a Kamikaze pilot to return, plus highly unlikely considering how much flak and AA you would have to take/avoid before you got anywhere near an Allied ship. Plus, later in the war, the Americans did manage to capture the fabled A6M Zero fighter plane, and modeled the F6F Hellcat on it's weaknesses. See the following.
http://www.youtube.com/watch?v=Juic9HiyAZE
It means simplistic or purposely untouched
