Definition
A navigation system that uses barometric altitude information from the aircraft's altimeter, combined with lateral guidance from an area navigation (RNAV) system, to compute and display a vertical descent path to a runway. On approved RNAV (GNSS) approaches, BARO VNAV allows the pilot to fly a stabilized, constant-angle descent to the LNAV/VNAV landing minimums published on the approach chart.
Plain English
A system that uses the aircraft's altimeter, together with lateral course guidance, to draw a steady downward path to the runway for the pilot to follow during an approach.
Context Anchor
Seen on instrument approach procedures and landing minimums where vertical guidance is provided by barometric altitude rather than by a ground-based glidepath.
Derivation
Baro is short for barometric, meaning 'measured by air pressure' (from Greek baros, weight). VNAV stands for vertical navigation. Together it means vertical guidance derived from a pressure-based altitude source rather than from satellites.
Why Pilots Care
It allows stabilized descents and potentially lower landing minimums without requiring satellite-based vertical guidance.
Grounding Statement
BARO VNAV builds a calculated downhill path from altitude information, so the quality of that path depends on the accuracy of the altitude information.
Intuition Check
Do not assume BARO VNAV is the same as a radio glidepath or satellite-based vertical guidance. The key word is “BARO”: it uses pressure-based altitude information from the aircraft.
Example Sentence 1
With the correct altimeter setting loaded, the crew flew the BARO VNAV descent down to the LNAV/VNAV minimums.
Example Sentence 2
With BARO VNAV available, the crew could follow vertical guidance down to the published minimums.