What is the main U.S. federal aviation regulation concerning aviation security?

The primary U.S. federal aviation regulation regarding aviation security is indeed found within the Title 49 of the Code of Federal Regulations (CFR), particularly the part 1500 series. This regulation establishes the framework for transportation security across different modes, including civil aviation. It is critical because it encompasses various security measures designed to protect travelers and maintain safety in the aviation sector.

Part 1500 includes guidelines and requirements that directly address the obligations of airports, airlines, and other entities involved in aviation to ensure comprehensive security protocols are in place. This includes personnel screening, airport access control, and measures to handle potentially hazardous materials, highlighting its central role in the broader context of aviation security.

In contrast, the other options focus on different aspects of aviation regulation. For instance, Title 14 CFR, part 77 pertains to safe, efficient use of airspace, while part 121 focuses primarily on the certification of operators for scheduled air carriers. Title 49 CFR, part 1520 involves the management and dissemination of security-sensitive information but does not encompass the broad regulatory framework of aviation security as a whole.