That video is from a Sikorsky film from the 1950's, and is of an H-37 (S-56) rotor blade. It was shot directly over the Sikorsky plant in Stratford Connecticut, the river has distinctive islands that mark the spot.
Makes you a believer in Helicopter Fatigue. Recal the thread in this forum where the number of banked turns per hour for a robinson was discussed. This film is all in level flight!
PS the link doesn't work for me