The US Federal Aviation Authority (FAA) has told airlines that there are MacBook Pros out there that cannot be brought onto commercial flights. The notebooks in question are those that were recalled by Apple earlier this year for official battery replacements. The FAA believes that these components are a fire hazard.
https://www.notebookcheck.net/The-FAA-bans-certain-MacBook-Pros-from-airplanes.430321.0.html