FAR Part 121

The Federal Aviation Regulations, or FARs, are rules prescribed by the Federal Aviation Administration (FAA) governing all aviation activities in the United States. The FARs are part of Title 14 of the Code of Federal Regulations (CFR). A wide variety of activities are regulated, such as aircraft design and maintenance, typical airline flights, pilot training activities, hot-air ballooning, lighter-than-air aircraft, man-made structure heights, obstruction lighting and marking, and even model rocket launches, model aircraft operation, sUAS & Drone operation, and kite flying. The rules are designed to promote safe aviation, protecting pilots, flight attendants, passengers and the general public from unnecessary risk. Since 1958, these rules have typically been referred to as "FARs", short for Federal Aviation Regulations. However, another set of regulations (Title 48) is titled "Federal Acquisitions Regulations", and this has led to confusion with the use of the acronym "FAR". Therefore, the FAA began to refer to specific regulations by the term "14 CFR part XX".

The FARs are organized into sections, called parts due to their organization within the CFR. Each part deals with a specific type of activity. For example, 14 CFR Part 141 contains rules for pilot training schools. The sections most relevant to aircraft pilots and AMTs (Aviation Maintenance Technicians) are listed below. Many of the FARs are designed to regulate certification of pilots, schools, or aircraft rather than the operation of airplanes. Once an airplane design is certified using some parts of these regulations, it is certified regardless of whether the regulations change in the future. For that reason, newer planes are certified using newer versions of the FARs, and in many aspects may be thus considered safer designs.

The FARs are divided into tens of thousands of separate sections, many of which have large numbers of researchers using them on any given day. A few of the regulations particularly interesting to laypersons, relevant to current political issues, or of historical interest are listed below.

Many other FARs depend on definitions, which are found in Part 1.1

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