Which regulation defines the flight into Class B airspace?

The regulation that defines the flight into Class B airspace is found in FAR Part 91. This part of the Federal Aviation Regulations outlines the general operating and flight rules that apply to all pilots and aircraft operations in the United States, including specific requirements regarding the use of airspace classes.

Part 91 establishes the rules regarding the entry into Class B airspace, including the necessity of obtaining clearance from air traffic control prior to entering that airspace. It also specifies the procedures pilots must follow when operating in and out of Class B airspace, ensuring safety and efficiency in one of the most congested airspace types.

FAR Part 121, in contrast, pertains primarily to the operation of scheduled air carriers, while FAR Part 135 regulates commuter and on-demand operations. FAR Part 145 focuses on repair stations and maintenance standards, none of which directly addresses the regulations governing operations into Class B airspace. Thus, Part 91 is the appropriate reference for understanding the rules and requirements for flying in this critical airspace.