What AIRAC actually is
Aeronautical Information Regulation and Control, AIRAC, is the ICAO-coordinated schedule that governs when changes to aeronautical information, new procedures, revised airways, changed frequencies, amended waypoints, take effect worldwide. Rather than publishing changes whenever they are ready, the entire aviation industry works to a shared calendar of effective dates spaced exactly 28 days apart, which is what lets every chart provider, database vendor, airline and ATC authority change their published information on the same day everywhere. Jeppesen's own cycle, for instance, sets its AIRAC effective dates on Thursdays at 28-day intervals.
Why a database expires on a schedule rather than simply going stale
A navigation database is a snapshot of the aeronautical information valid for one AIRAC cycle. Waypoints move, frequencies change, procedures are amended or withdrawn, and a database built to an old cycle does not gradually become slightly wrong, it becomes wrong to the extent that anything changed in the cycles since it was current. Because every provider aligns to the same 28-day calendar, "current" and "expired" have a precise, shared meaning across the industry rather than being a vague notion of how old the data feels.
What is actually being updated
Jeppesen describes reviewing roughly 47,000 source data pieces and editing or verifying close to 600,000 database transactions on average per cycle, covering navigation aids, approach procedures, airways, waypoints, SIDs and STARs, plus operator-customisable elements such as company routes and airport gates. That volume of change, every 28 days, is the reason a subscription model exists at all rather than a database being a one-time purchase.
Where ASPL fits into this
ASPL supplies navigation database subscriptions across the major providers used in Indian operations: Garmin Database Update for Garmin portable and panel avionics, Jeppesen Database Update for the wide range of flight management systems and simulators Jeppesen NavData supports, and Honeywell / Bendix King Database Update for Honeywell and Bendix King avionics, which draw their base navigation data from Jeppesen as the sole source. Which one applies to a given aircraft depends entirely on the avionics fitted, not on operator preference, and getting the wrong subscription for the installed equipment is a straightforward but avoidable mistake.
What flying on an expired cycle actually risks
The consequence is not usually a dramatic failure. It is more often a subtle mismatch: a waypoint that has been renamed or relocated, a procedure that has been amended with a new minimum altitude, a frequency that has changed. On a VFR flight in familiar airspace, an expired database might make no practical difference at all for weeks. On an IFR approach flown to published minimums, it is a different matter entirely, and it is why an outdated database is treated as an operational issue in instrument flying rather than a housekeeping one.
Keeping the routine simple
- Know which provider's database each piece of equipment in your aircraft actually uses, since Garmin, Jeppesen and Honeywell/Bendix King subscriptions are not interchangeable.
- Subscribe on a schedule that matches the 28-day AIRAC cycle rather than updating irregularly.
- Update before the cycle you are relying on for a flight expires, not after you notice a discrepancy in the air.
- For fleets running mixed avionics, track subscriptions per aircraft type rather than assuming one renewal covers everything.
ASPL supplies and renews these subscriptions for operators across Garmin, Jeppesen and Honeywell/Bendix King avionics in India, so a mixed-equipment fleet has one place to keep every database current.