In a two-part series from The Boston Globe, the Spotlight Team focused on the Federal Aviation Administration, which is supposed to keep track of every American plane, pilot and airplane mechanic at its offices in Oklahoma City. But their record-keeping system allows so much secrecy and relies so heavily on self-reporting of crimes and other misdeeds that the United States has become a haven for people with something to hide, especially drug dealers, corrupt individuals and people with ties to terrorism. 

Day 2: http://apps.bostonglobe.com/spotlight/secrets-in-the-sky/series/part-two/

Sidebar on the use of U.S. airplanes by foreign officials: http://www.bostonglobe.com/metro/2017/09/23/the-king-swaziland-gift-showcases-lure-american-plane-registration-foreign-leaders/us6KCUGUxZhkgqvDj9UW9O/story.html