FAA Instrument Flight Instructor (FII)IFR Procedures and ApproachesHard
A pilot is flying an RNAV (GPS) approach with LNAV/VNAV minimums. The aircraft is equipped with WAAS, and the GPS receiver indicates 'LNAV+V' active. What does 'LNAV+V' signify in this context?
- ALateral navigation with VOR overlay guidance.
- BLocalizer performance with vertical guidance, similar to an ILS.
- CLateral navigation with advisory vertical guidance, but not to LPV precision standards.
- DLateral navigation with visual approach guidance.
Show answer & explanationAnswer & explanation
Correct answer: C. Lateral navigation with advisory vertical guidance, but not to LPV precision standards.
LNAV+V provides advisory vertical guidance based on a barometric VNAV or WAAS-derived path, but it does not meet the stringent precision and integrity requirements of an LPV approach. It keeps the pilot above the MDA until the VDP, or if no VDP, to the MAP, but it is not considered precision guidance.
Why the other options are wrong
- A. LNAV is purely GPS-based lateral navigation; VOR overlay is a separate concept.
- B. This describes LPV, which offers ILS-like precision, but LNAV+V is advisory vertical guidance.
- D. Visual approach guidance is typically generated by the pilot or from ground-based visual aids, not 'LNAV+V'.
LNAV+V Indication
LNAV+V (Lateral Navigation with advisory Vertical guidance) is a GPS approach capability that provides a computed vertical path for advisory use, typically based on WAAS data, but does not offer the precision of LPV minimums.
- Provides a descent path to or above the MDA.
- Does not meet precision approach standards.
- Often used when LPV is not available or not selected.
Memory trick: LNAV+V, vertical advisory, but not LPV.