What should the FA do if they notice a passenger behaving suspiciously?

The appropriate action for a flight attendant when noticing suspicious behavior from a passenger is to immediately inform the captain. This response is critical for ensuring the safety and security of all individuals on board the aircraft. The captain is responsible for the overall management of the flight and is trained to handle such situations effectively. By reporting to the captain, the flight attendant enables the crew to assess the situation, take necessary precautions, and, if needed, contact authorities or prepare for an emergency response.

This protocol not only protects passengers but also helps in maintaining order and preventing potential threats. Effective communication among crew members is essential in these circumstances, allowing for a unified approach to safety and security. The captain can then make informed decisions based on the nature of the situation reported by the flight attendant.