Well, they usually don't have variable pitch. But there are a few rare examples of variable pitch quadcopters, for instance this monster from Curtis Youngblood:

Well, they usually don't have variable pitch. But there are a few rare examples of variable pitch quadcopters, for instance this monster from Curtis Youngblood: http://www.curtisyoungblood.com/legacy-product-support-curtis-youngblood/attachment/stingray-500/ http://www.curtisyoungblood.com/legacy-product-support-curti...