Secret Planes:
Click on the very small plane dot a little more than half-way down on the right side of the Select Mission Screen.This will get you all secret planes...including the Raptor,Flying Saucer...and so on.Enjoy!

Extra Points:
On mission 6 go near the top of B3 and you will see an island. Destroy the tree on the island and it will say enemy Bill Mooney's favorite tree destroyed +500 points!

Strategy:
On the 3rd level you should be at the same altitude as the Japanese Airplanes. How you can tell if your the same altitude is the arrow's!if the arrows are green your on the same altitude as the planes! if the arrows are red and are pointing down go up until the arrows are green. If the arrow's are red and going up go down until the arrows are green.