What is the role of WAAS-certified GPS equipment during RNAV (GPS) approach procedures?

The correct answer highlights the role of WAAS-certified (Wide Area Augmentation System) GPS equipment in providing vertical glide path information during RNAV (GPS) approach procedures. WAAS significantly improves the accuracy and integrity of GPS signals, allowing pilots to receive precise vertical guidance in addition to lateral guidance. This is essential for conducting approaches that feature specific glide path angles, permitting a more controlled descent and enhanced safety for landing procedures.

During an RNAV approach, vertical guidance is crucial for ensuring that the airplane follows the correct flight path to the runway. The use of WAAS equips pilots with the tools necessary to navigate approaches more precisely, thereby enhancing overall flight safety and operational efficiency.

WAAS-enabled GPS does not solely provide lateral guidance — that capability is fundamental to all GPS systems. It also does not enhance VOR signals, as it relies on satellite-based navigation. Moreover, while it does facilitate precision approaches, the distinction of also providing vertical glide path information is what uniquely benefits pilots using this advanced technology during RNAV approaches.