Plain English Meaning
An approach where the GPS-based system guides the airplane both side-to-side toward the runway and up-and-down along a descent path. Instead of stepping down to a flat minimum altitude, the pilot follows a smooth glide path down to a decision altitude, where they either see the runway and land or go around.
Full Definition
An instrument approach service that provides both horizontal (lateral) course guidance and vertical descent guidance to a runway, using satellite-based navigation systems with augmentation that meets accuracy and integrity standards for vertical guidance. LNAV/VNAV approaches publish a Decision Altitude (DA) rather than a Minimum Descent Altitude (MDA), and the vertical path is computed by the aircraft's flight management system or generated by SBAS (such as WAAS).
Context Anchor
Seen on RNAV approach charts as an LNAV/VNAV line of minimums, and in avionics when the system is providing both side-to-side guidance and descent-path guidance.
Derivation
Lateral comes from Latin lateralis, meaning 'of the side' — side-to-side guidance. Vertical comes from Latin verticalis, meaning 'of the highest point' — up-and-down guidance. Together they describe an approach guided in both dimensions, like an ILS but built from satellite data instead of ground-based radio beams.
Why Pilots Care
It gives lower decision heights than LNAV-only approaches, letting pilots land at more airports in marginal weather.
Analogy
Think of it like driving with lane guidance and hill guidance at the same time: one part keeps you lined up left and right, and the other tells you the proper path down. LNAV/VNAV does both for an instrument approach.
Grounding Statement
On an LNAV/VNAV approach, the aircraft is being guided toward the runway in two ways at the same time: centered on the course and descending along a calculated path.
Intuition Check
Do not assume VNAV guidance is the same as an ILS glideslope. LNAV/VNAV has its own equipment requirements and its own published limits.
Example Sentence 1
Approach cleared us for the RNAV (GPS) Runway 27 approach, and we briefed the LNAV/VNAV minimums since our aircraft was equipped for vertical guidance.
Example Sentence 2
With LNAV/VNAV armed, the autopilot captured the glidepath and began a steady descent toward the threshold.