Helicopters can’t fly without using their rotor blades, so to see one gliding through the air with its rotor completely still is a somewhat surreal sight. Check out the video below to see what we mean. It was recently published by a YouTube user called Chris Fay, but before you start freaking out, there’s a very logical explanation for this seemingly impossible occurrence. Far from defying gravity, the helicopter’s rotors were simply perfectly synchronized with the camera’s shutter speed. For those who don’t know, the shutter speed is the amount of time cameras spend gathering light. The longer it’s open, the more motion blur you’ll see, but when your shutter speed is high then it can create bizarre visual distortions like the one you can see in the video.

More info: YouTube

See below to learn why helicopter blades often look strange on video: