The funding authorization for the Federal Aviation Administration (FAA), included in the FAA Modernization and Reform Act of 2012 (P.L. 112-95), expires on September 30, 2015. In addition to setting spending levels, FAA authorization acts typically set policy on a wide range of issues related to civil aviation. This report considers topics that are likely to arise as the 114th Congress debates reauthorization. Most FAA programs are financed through the Airport and Airway Trust Fund (AATF), sometimes referred to as the Aviation Trust Fund. The financial health of the AATF, which is funded by a variety of taxes and fees on air transportation, has been a growing concern. Although the trust fund balance is projected to grow in the near term-as AATF revenue continues to rise and airport capital needs are projected to decline-reductions in general fund appropriations to FAA have increased the proportion of FAA funding that is derived from the trust fund. In addition, changes in airline business practices pose a risk to the AATF revenue structure: trust fund revenue is largely dependent on airlines' ticket sales, and airlines' increasing use of fees charged for options that may once have been included in the base ticket price, such as checked bags and onboard meals, has reduced the amount of money flowing into the fund.