what is the difference between LPV and LNAV/VNAV? I need examples of both approaches

LPV (Localizer Performance with Vertical guidance) and LNAV/VNAV (Lateral Navigation/Vertical Navigation) are both types of approaches used in aviation for guiding aircraft during descent and landing, but they utilize different systems and provide different levels of guidance and accuracy. ### LPV (Localizer Performance with Vertical Guidance) **Description:** - LPV approaches are Precision APproaches that utilize the Global Positioning System (GPS) and are based on the Wide Area Augmentation System (WAAS) in the United States. LPV approaches provide lateral and vertical guidance similar to an ILS (Instrument Landing System) but do not require ground-based navigation aids. - LPV approaches can provide vertical guidance down to 200 feet Decision Height (DH) or 250 feet Minimum Descent Altitude (MDA), depending on the specific approach. **Example:** - An example of an LPV approach is the LPV approach to Runway 26 at San Carlos Airport (KSQL) in California. This is a GPS-based approach that uses WAAS to provide both lateral and vertical guidance to pilots. ### LNAV/VNAV (Lateral Navigation/Vertical Navigation) **Description:** - LNAV/VNAV approaches use GPS for lateral guidance (LNAV) and require an additional system, usually based on barometric altitude, for vertical navigation (VNAV). They can provide vertical guidance down to a Decision Height of 250 feet, but they typically do not offer the same precision as LPV. - The vertical guidance in LNAV/VNAV approaches is based on the aircraft's barometric pressure settings and the associated descent path, which may lack the integrity of the WAAS system used in LPV approaches. **Example:** - An example of an LNAV/VNAV approach is the approach to Runway 13 at Westfield-Barnes Regional Airport (KBAF) in Massachusetts. This approach utilizes GPS for lateral navigation and a barometric system for vertical navigation. ### Key Differences: 1. **Guidance Type:** - LPV provides both lateral and vertical guidance based on WAAS GPS, while LNAV/VNAV provides lateral guidance from GPS and vertical guidance from barometric altitude. 2. **Precision:** - LPV approaches are usually more precise than LNAV/VNAV approaches and can reduce the minimums for landing. 3. **Equipment Requirements:** - LPV requires specific certified GPS equipment that supports WAAS. LNAV/VNAV requires basic GPS with VNAV capabilities and a compatible altimeter system. 4. **Operational Use:** - LPV is often viewed as a more advanced and accurate approach and can be compared to ILS, while LNAV/VNAV approaches are used where WAAS is not available or for aircraft not equipped for LPV. In summary, LPV is typically more precise, utilizes WAAS for vertical guidance, and can often have lower minimums compared to LNAV/VNAV which relies on barometric altitude for vertical guidance.