The Hellcat was a nasty surprise to the Japanese pilots. I recall reading about a high scoring Japanese ace who liked to zoom climb his Zero and would bait Wildcat pilots into trying to follow. He would time it so the Wildcats would stall and fall out of pursuit, just as he did a wingover and dove back down on the helpless Americans, scoring easy kills. His first(?) time against a Hellcat, he must have thought he was fighting a Wildcat, however. He did his wingover but found the American plane still climbing, so HE became the easy kill as he turned right in front of the American's guns. Ouch!
-Irish