"The Airport Improvement Program (AIP) has been providing federal grants for airport development and planning since the passage of the Airport and Airway Improvement Act of 1982 (P.L. 97-248). AIP funding is usually spent on projects that support aircraft operations such as runways, taxiways, aprons, noise abatement, land purchase, and safety or emergency equipment. The funds obligated for the AIP are drawn from the Airport and Airway Trust Fund (hereafter referred to as the trust fund), which is supported by a variety of user fees and fuel taxes. The AIP is one of five major sources of airport capital development funding. The other sources are tax-exempt bonds, passenger facility charges (PFCs: a local tax levied on each boarding passenger), state and local grants, and airport operating revenue. Different airports use different combinations of these sources depending on the individual airport's financial situation and the type of project being considered. Small airports are more dependent on AIP grants than large or medium-sized airports […] During the FAA [Federal Aviation Administration] reauthorization debate in the 110th Congress, virtually all of the policy issues and options concerning AIP will be influenced by the broader budget issues of the adequacy of trust fund revenues and the availability of money for the FAA from the Treasury general fund. Should ample revenues be available, the reauthorization of AIP could maintain the program's structure and perhaps even increase AIP spending. A constrained-budget scenario would probably increase interest in such issues as defederalization or a tightening of program formula funding and eligibility criteria, which could provide cost savings. It could also increase interest in raising or eliminating the PFC ceiling, which could help airports fund more projects, either directly or by supporting increased bonding."
CRS Report for Congress, RL33891