***Link*** :: [Guidance for Localizer Performance with Vertical Guidance and Localizer Performance without Vertical Guidance Approach Operations in the U.S. National Airspace System](https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_90-107.pdf) ***Description*** :: `= this.link` ***Author*** :: [[FAA]] ***Related To:*** [[Satellite Navigation using GPS and GNSS]] #### Key Quotes * This advisory circular ([[AC]]) provides guidance for operators to conduct Title 14 of the Code of Federal Regulations (14 CFR) part 97 instrument flight rules ([[IFR]]) Area Navigation ([[RNAV]]) Global Positioning System ([[GPS]]) instrument approach procedures ([[IAP]]) with localizer performance with vertical guidance ([[LPV]]) and localizer performance without vertical guidance ([[LP]]) lines of minima using the wide area augmentation system ([[WAAS]]). * **Contingency Procedures**. Pilots must be familiar with the fail-down capability of their WAAS integration. * Example: LPV or LP lines of minima approach not available due to reduced WAAS service. * Example: Complete GPS service outage or avionics malfunction. When a GPS service outage occurs all RNAV (GPS) approaches will be out of service. #source #advisory-circular