How Airplanes Land in Low Visibility

In cloud or fog, a runway may remain invisible while an airplane is already aligned with it and descending along a precise path. The airplane is not guessing. Ground transmitters or approved satellite-based procedures provide lateral and vertical guidance. Cockpit instruments show deviations. Trained crews and, on suitably equipped aircraft, automatic systems follow that guidance under strict limits. General aviation education only, not flight instruction, maintenance guidance, or a substitute for approved manuals and trained professionals. Sources and further reading: - FAA, Instrument Landing System: https://www.faa.gov/about/office_org/headquarters_offices/ato/service_units/techops/navservices/gbng/ils - FAA Advisory Circular 20-191, Aircraft Low-Visibility Operations: https://www.faa.gov/regulations_policies/advisory_circulars/index.cfm/go/document.information/documentID/1033172