CatCopter in flight during the GogBot Festival in Enschede (2012). 
This is a <a href="https://en.wikipedia.org/wiki/Quadrotor" class="extiw" title="w:Quadrotor">Quadrotor</a>; also called a quadrotor helicopter or quadcopter, is a <a href="https://en.wikipedia.org/wiki/multirotor" class="extiw" title="w:multirotor">multicopter</a> that is lifted and propelled by four <a href="https://en.wikipedia.org/wiki/Helicopter_rotor" class="extiw" title="w:Helicopter rotor">rotors</a>.
<a href="//commons.wikimedia.org/wiki/User:Kleuske" title="User:Kleuske">Kleuske</a>
<span class="int-own-work" lang="en">Own work</span>