The Full Form of BCAS is  Bureau of Civil Aviation Security.

The Bureau of Civil Aviation Security (BCAS) is an attached office of the Ministry of Civil Aviation (India). It is the regulatory authority for civil aviation security in India. It is headed by an officer of the rank of Director general of police and is designated as Director general of Security (Civil Aviation). Director General of security (DG BCAS) is the appropriate authority for implementation of Annexure 17(Security: Safeguarding International Civil Aviation Against Acts of Unlawful Interference) to Chicago convention of International Civil Aviation Organization. Director General of security (CA) is responsible for the development, implementation and maintenance of the National Civil Aviation Security Programme.