Right I am frustrated at the fact my tanks at full yet after 2 direct hits on varis who's a group captain he didn't get taken down by me however if it was the other way around I reckon he would of taken me down. Has anyone else had this problem?

I hope the attachment shows up fully cause that has frustrated me big time cause how can someone survive 2 direct hits and able to get a kill?

that just means lot of lag, I have to figure out a way to handle better the tanks shots

There is another possible reason than lag:

I fear I didnt understand you very well, Delirious, but if you are telling about hitting an airplane from a tank and nothing happening, I can tell you that (though hard to believe), if you aim at the very tip of the plane's nose and shoot at it from tank, chances are that the plane's bullets will colide with the tank's shell, making it explode in mid-air, before hitting the plane. Seen from the tank, it looks like the shell hits the airplane, but it actually blew mid-air.
In other two occasions, I noticed TWO TANK SHELLS COLLIDING AGAINST EACH OTHER, on tank battles. I witnessed it TWICE, believe me.
Tip: when shooting at airplanes, go for the wings, dont aim at the body of the airplane. Since I begun making this way, I begun to kill more planes, and no more lost exploding shells.

yeah that can also happen... that a gun bullet hits the tank bullet and it explodes near the airplane

Possibly another cause, different platform. I have noticed that different playing platforms perform diff. it seems as though the plane is actually a bit higher or lower. The same reason some planes seem to fly underground once in a while.
I have found that if I shoot a bit high and to the right it seems to be a better target area for a kill shot.