How is the FMS navigation database structured and maintained?

The FMS navigation database contains: Waypoints (coordinates, names), Airways (routes between waypoints), Airports (runways, frequencies, procedures), Navaids (VOR, NDB, ILS parameters), Standard procedures (SIDs, STARs, approaches), Holding patterns, Company routes, and Performance data. Database format follows ARINC 424 specification. Updates occur on 28-day AIRAC cycle to match published changes. Validation includes: Data integrity checks, Procedure flyability verification, and Operational approval testing. Loading via data loader or network connection. Database accuracy is critical - errors can cause navigation errors or violations of terrain/airspace. Configuration management ensures correct database installed.