Airs can't do them why?

Dudes, I'm new here. I need some advice I'm goofy. At the moment the waves are really glassy and predictable where I'm surfing so I do my bottom turn then pump along the face to get speed, I'm all speeding up and the wave is a great one peeling left and then near the end of the ride the right side peels too, so I guess it's perfect for airs just at that point where the two peeling sides meet. I can also have loads of speed at that point, my problem is I suck at getting airs. I can do roller coasters, off the lips, floaters but not pull off an air where I go above the wave and land down. I either fall off the wave, or the board nearly hits my face or I go over the back of the wave like a kook and the board doesn't follow. I've been watching the WCT at Lowers and those guys make it look so easy that I'm pshyched up and think next time I'll pull an air like that but it never happens. It's been about 6 months I've been trying when a good wave comes but nothing good. How do I do it? My board is a 5.6 squash tail and I'm 5.6 too and 55 kg, I used to skate and could pull great ollies and airs so I know what it feels like just not on water.
Please help.
Please help.