Verifying Engine RPM readings (Camera Method)

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Verifying Engine RPM readings (Camera Method)

Postby Rynoth » Sun May 24, 2020 6:47 pm

Most consumer grade cameras (including most phones, tablets, etc) record video in 60 frames per second. An interesting phenomenon that happens with footage taken with these cameras is either a reversal in the "apparent" motion of the propeller from clockwise to counter-clockwise (or vice versa), or a still image of the propeller altogether, when the propeller is at 1800 RPM. Since 1800 RPM lies easily within the range of most aircraft propellers, a verification check can be made with a camera that the tachometer is reading correctly. Obviously one would want to verify that the video being taken is actually at 60 frames per second with the camera device being used.
Ryan Roth
N197RR - Waiex #197 (Turbo Aerovee Taildragger)
Knoxville, TN (Hangar at KRKW)
My project blog: http://www.rynoth.com/wordpress/waiex/
Time-lapse video of my build: https://www.youtube.com/watch?v=Q8QTd2HoyAM
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