If a prohibited article is found during security checks, who must be informed immediately?

Informing the commander immediately when a prohibited article is found during security checks is crucial because they hold the ultimate responsibility for the safety and security of the aircraft and its passengers. The commander is tasked with making critical decisions regarding the management of security incidents, including assessing any potential threats posed by the prohibited item and determining the appropriate course of action. This includes evaluating the nature of the article, considering passenger safety, and liaising with ground support or security authorities as needed.

In contrast, while the other roles are vital for the operation and safety of the flight, they may not have the authority or responsibility to handle security breaches in the same way as the commander. The captain, first officer, and chief flight attendant play important roles but reporting to the commander ensures that the most qualified person to make high-level decisions regarding security is promptly informed and can act accordingly.