This video demonstrates the behavior of a defective OEM motor on the Syma X11 Quadcopter. The prop immediately coming to a stop when the throttle is cut indicates an internal problem with the motor that is causing excessive friction, preventing it from achieving sufficient speed to perform correctly. It also heats to excessively high temperatures while running. This is not a condition caused by the gearing which was inspected to assure a normal operation as seen in the other three.
This condition accelerated quickly over the course of the first 4 flights, from a state of mild friction when out of the box brand new, to the state seen here. The behavior observed during this time frame was a growing increase in the amount of throttle required to keep the quad airborne. In the latter part of the forth flight the motor rapidly lost power and was no longer able to sustain flight even at max throttle. Upon landing, the motor was extremely hot. At the time of this filming, after running at approximately 50% throttle for about one minute, the motor reached a temperature of almost 160 F.
