Consider that your jet may sit unwatched at a foreign airport while you and your pilots are staying at a hotel. Even if you lock the aircraft and secure the door with seals, can you be certain that a foreign intelligence service has not compromised your security measures and surreptitiously installed a transmitter or recorder inside your aircraft?
In the 1990’s, it was discovered that French intelligence had installed audio recorders in the first class seating areas of Concorde jets in order to collect intelligence from business executives. Modern smaller and more effective surveillance devices pose greater threats today.
Have your jet examined on a regular basis to be sure your conversations are secure, especially if you have recently traveled overseas.