For months, Americans were left in the dark, watching in shock as mysterious drones swarmed the skies over multiple states.

The FAA has said that all controllers have to meet tough testing and training standards and go through a lengthy certification process.

This week, the White House's latest revelations involving the ongoing "mystery drone" saga only raise more questions.

A look at the frequency of runway incursions in the United States and the preventative measures taken by the FAA to avoid ...