Researchers from the University of Zurich’s Robotics and Perception Group have proven that this does not need to be the case by keeping a quadcopter flying with only three motors. A quadcopter ...

[Michael Melchior] wanted to scavenge some motors and propellers for another project, so he bought an inexpensive quadcopter intending ... from reading—write protection hadn’t been enabled ...

A quadcopter however, uses four motors connected to four fixed-pitch props. They are literally propellers attached directly to motors, a sum total of a single moving part for each of the four props.