Which approaches permit VNAV with the flight director or autopilot coupled during climb and approach?

• A. LPV and LNAV/VNAV approaches
• B. ILS and Localizer approaches
• C. VOR and DME approaches
• D. RNAV (GPS) and ILS approaches

Answer: (A)

VNAV with the flight director or autopilot coupled works when the approach provides a published vertical path that the navigation system can follow. LPV and LNAV/VNAV are RNAV-based approaches that include vertical guidance. LPV uses SBAS to supply a precise descent profile similar to a precision approach, while LNAV/VNAV provides a vertical path via baro-VNAV or SBAS data. Because this vertical guidance is built into the approach data, the flight director or autopilot can couple to it and fly the climb and the approach along that vertical path. ILS does provide vertical guidance, but it’s via the ground-based glideslope, not a VNAV path from the navigation database, so it isn’t VNAV-driven. VOR and DME offer no vertical guidance. RNAV (GPS) by itself isn’t guaranteed to have vertical guidance unless it’s the LPV or LNAV/VNAV variant, which is why LPV and LNAV/VNAV are the correct choices.