The Federal Aviation Administration (FAA) has tasked Tetra Tech to help improve the technology and functionality of its navigation infrastructure. Tetra Tech provides engineering and technical support for planning, research, development, implementation, sustainment, and decommissioning efforts as FAA transitions to an integrated ground- and satellite-based navigation systems architecture.

Tetra Tech supports FAA's modernization initiatives, including its Next Generation Air Transportation System (NextGen), by supporting the design of performance-based navigation (PBN) procedures, complying with environmental regulations, performing airspace environmental assessments, and performing noise footprint evaluations to enable increased capacity and enhance efficiency in the U.S. National Airspace System (NAS).

Tetra Tech has been providing FAA with engineering, technical, operations, and satellite support to expand GPS capabilities by implementing new satellite navigation technology to make aviation flight safer, more efficient, and more cost-effective. Tetra Tech assisted in deploying the Wide Area Augmentation System (WAAS), an FAA-developed system that improves GPS accuracy, availability, and integrity. The alliance between FAA and Tetra Tech resulted in great achievements, such as the WAAS commissioning in 2003; the development of more than 3,000 LPV approaches in the United States; the development of the first WAAS LVP approaches for Helicopter Medical flights; and the development of the first FAA-approved Instrument Flight Rule/arrivals and departures routes used by Mercy Medical Center in Des Moines, Iowa.

Tetra Tech also provides systems and safety engineering and operations management support to FAA’s Navigation Services office to rationalize the remaining conventional navigation infrastructure to most effectively enable future NextGen capabilities such as Required Navigation Performance and to support development of alternate positioning, navigation, and timing services. To date, Tetra Tech has assisted FAA in developing and implementing more than 1,000 PBN procedures into the NAS.