I watched the video, here are the problems that I've spotted:
-Helicopter looks to fat in the back(maybe it's meant to be like this, like a different or made up heli model type)
-Planes look totally unrealistic.
-The animation for the guy dying looks like he's falling in slow motion.
-The trees don't look all that realistic.
-Shadows on the water.
-Waters way too bright.
-Buildings have too few faces.
-The sun doesn't look very round.
-The planes shadow seems to disappear between 00:02 and 00:03 seconds, when the planes fly onward off the screen via the top edge of the screen.
-The helpcopters blades are way way way way way too slow.
-This is more a recommendation then a problem, but you may want to add effects in the water when the helicopter goes over the river.
Other than those, I think it's pretty good.
I would gladly offer to assist in fixing some of these issues, but I know you're going to say no.
No offense, I just want to be thorough and help ensure that the final product is top quality.