The Feeral 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 airplane design, typical airline flights, pilot training activities, hot-air ballooning, lighter than air craft, man-made structure heights, obstruction lighting and marking, and even model rocket launches and model aircraft operation. The rules are designed to promote safe aviation, protecting pilots, passengers and the general public from unnecessary risk. They are also intended to protect the national security of the United States, especially in light of the September 11, 2001 attacks.