Flying machine creates invisible blocks water floats on

I created a flying machine that flies horizontally through a waterfall. Whenever the flying machine passes through the waterfall, the water stays floating in the air where the machine passed through, even after it's already out of the way, which should allow the water to go back into a resting position. Instead, the water just floats in midair.

 

I have a video as well, but it is 428 MB and exceeds the maximum size limit.