CAT III and Low Visibility Procedures Explained
CAT III is the category of instrument landing that allows aircraft to land in very low visibility, even in dense fog. It requires special equipment on the runway, special aircraft certification and trained crews.
The categories
Instrument approaches are grouped by how low the pilot may go and how little visibility is allowed. CAT I is the standard; CAT II and CAT III permit lower minimums. CAT III has sub-categories, with the lowest allowing landing with very little visual reference, using the autopilot to land the aircraft. See ILS, RVR, autoland and CAT III.
What is needed
- A runway with a suitable ILS and approved lighting and surface markings.
- Ground movement controls so aircraft and vehicles do not get lost in fog.
- A certified aircraft with autoland capability.
- A trained and approved crew and an airline authorised for the operation.
If any element is missing, the airline must use higher minimums, and flights may be held or diverted.
Low-visibility procedures
When visibility falls, airports activate procedures: fewer aircraft on the ground at once, restricted taxi routes and protected areas around the runway. These slow operations, so some delay is normal even when flights continue.
What it means for passengers
Airports and airlines that can operate in lower visibility keep flights going longer during fog. We cannot list which Pakistani runways or airlines are approved, because it changes and is not in our data; check with the airline and the Civil Aviation Authority.
General information only, not legal or safety advice. Details change; check with your airline and the relevant authority. See our editorial policy.