Because vanilla Generals isn't good enough for you. Realism overhauls and graphical enhancements are the main points of existence of this mod. If you want tons of new units, this is not the mod for you.
This is only a module to simulate C&C3 effects when a helicopter passing through either land or water and create surface effects. Don't ask how I did it because I just did it xD, it's not as simple as you think but for those who "Really" wants to know, here's a clue:
"Dare not look to only one side but both. Look not only to the sky but the great plate where you're standing. Dare not look to what you've observed but what that's beyond it"
-Decrypt this passage to gain what it takes to accomplished this :D