Gemfan Propeller 5x4.5 Black (CW/CCW) (2pcs)

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Certified Buyer Rated

Jul 23, 2016

cheap but great performance

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Customer Rated

Feb 17, 2016

These props are very stiff and well shaped.
[WARNING] However, the structural integrity of these props are nearly impossible to verify after a crash. I was tuning PIDs for a 250 quad (using 2150kV MS Elite 'Mini Monster' motors and a 4S battery) and had a few rough landings. After the first prop broke, I carefully checked each prop after each flight, as they were snapping at the root.
I finally had the PID's tuned in to prevent oscillation at ~50pcnt throttle, so I tried gunning the throttle to see how it handled at ~80pcnt throttle.

In a split-second, 7 out of the 8 total blades on my quadcopter exploded / ripped apart mid-air and the quad fell to the ground. Some blades flew more than 10 meters, one blade had flown inwards and ripped ~4cm of heatshrink off the side of my video TX and one propeller was found in at least 3 pieces, split down the length of the blade into slivers.

While I cannot recommend these props for a quad using the same high-power motors and 4S battery setup, I do believe these props operate fine with a more moderate / 3S setup.

Here is a link to a video of the incident: https://www.youtube.com/watch?v=8Ut29iIa2xw

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Certified Buyer Rated

Jul 10, 2015

toste. davvero toste