University of Michigan Survival Flight (N155UM) lifting from the Mid-Michigan Medical Center

Filmed on 12-28-16. N155UM - 2011 Eurocopter Ec-155 B1. Owned and Operated by Metro Aviation. I was visiting my grandma over break and I heard it flying over, so we left to see it. I just missed the actual engine start, but i got 95% of the start up. In the video, I captured a visual Phenomenon of the rotors matching the frame rate of my camera. Hope you enjoy!