The Code of Federal Regulations (CFR) is the codification of the general and permanent rules published in the Federal Register by the executive departments and agencies of the Federal Government. It is divided into 50 titles that represent broad areas subject to Federal regulation.
AIR CARRIERS AND OPERATORS FOR COMPENSATION OR HIRE: CERTIFICATION AND OPERATIONS - (SUBCHAPTER G)
Certification: Air Carriers and Commercial Operators (Part 119)
Operating Requirements: Domestic, Flag, and Supplemental Operations (Part 121)
Certification and Operations: Airplanes Having A Seating Capacity of 20 or More Passengers or a Maximum Payload Capacity of 6,000 Pounds or More; and Rules Governing Persons on Board such Aircraft (Part 125)
Operations: Foreign Air Carriers and Foreign Operators of U.S.-Registered Aircraft Engaged in Common Carriage (Part 129)
This FAA database is a searchable repository of all aviation safety Advisory Circulars (ACs).
Advisory Circulars define an acceptable means of complying with the published regulations as well as describing the intent and applicably of the regulations. ACs are often published in a "simple English" format which many find easier to read than the "legalese" of the regulations themselves.
You can look at the most current ACs by their AC Number, or Regulatory Part Number (CFR, CAR...). It is also possible to view historical AC information to see old or cancelled ACs. For each AC, you can view a pdf copy.
FAAA Flight Standards Information Management System
FAA Flight Standards holds the standards and oversight of most aviation service industries ranging from flight to maintenance and nearly everything in between other than component and aircraft manufcaturing.
The FSIMS directs the activities of the FAA Flight Standards Aviation Safety Inspectors (ASI) who are responsible for the certification, technical administration, and surveillance of air carriers, certain other air operators who conduct their operations in accordance with the appropriate part of Title 14 of the Code of Federal Regulations (14 CFR), certificated airmen and other aviation activities.
This order also provides direction for tasks related to aircraft accidents and incidents, investigations and compliance, the aviation safety program, administrative areas, and miscellaneous tasks not related to a specific regulation. In addition, it contains regional and district office requirements for the support of ASIs responsible for those activities.
Understanding what the ASI is looking for when approving aviation businesses or conducting routine audits is a valuable business tool.